Information on EC 2.7.7.8 - polyribonucleotide nucleotidyltransferase

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The expected taxonomic range for this enzyme is: Bacteria, Eukaryota, Archaea

EC NUMBER
COMMENTARY
2.7.7.8
-
RECOMMENDED NAME
GeneOntology No.
polyribonucleotide nucleotidyltransferase
REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
RNAn+1 + phosphate = RNAn + a nucleoside diphosphate
show the reaction diagram
PNPase exhibits 3'-to-5' exonucleolytic activity
-
RNAn+1 + phosphate = RNAn + a nucleoside diphosphate
show the reaction diagram
PNPase exhibits 3'-to-5' exonucleolytic activity
-
RNAn+1 + phosphate = RNAn + a nucleoside diphosphate
show the reaction diagram
stem-loops of 7,9 or 11 bp block the processive 3'-5' exonuclease action of PNPase
-
RNAn+1 + phosphate = RNAn + a nucleoside diphosphate
show the reaction diagram
analysis of the different PNPase domains for polymerization, degradation, and RNA binding properties
Q41370
RNAn+1 + phosphate = RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
-
REACTION TYPE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
nucleotidyl group transfer
-
-
-
-
PATHWAY
KEGG Link
MetaCyc Link
Purine metabolism
-
Pyrimidine metabolism
-
SYSTEMATIC NAME
IUBMB Comments
polyribonucleotide:phosphate nucleotidyltransferase
ADP, IDP, GDP, UDP and CDP can act as donors.
SYNONYMS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
AtcpPNPase
-
i.e. Arabidopsis thaliana chloroplast PNPase
AtmtPNPase
-
-
chloroplast PNPase
-
-
chloroplast PNPase
Arabidopsis thaliana Col-0.
-
-
-
cpPNPase
Arabidopsis thaliana Col-0.
-
-
-
hPNPase(old-35)
-
-
hPNPaseold-35
-
-
hPNPaseold-35
-
-
nucleoside diphosphate:polynucleotidyl transferase
-
-
-
-
nucleotidyltransferase, polyribonucleotide
-
-
-
-
PNPase
-
-
-
-
PNPase
Bacillus subtilis BG214
-
-
-
PNPase
Caulobacter vibrioides NA1000
-
-
-
PNPase
A5EXU0
-
PNPase
A7ZS61
-
PNPase
P05055
encoded by pnp
PNPase
Escherichia coli JM83
-
-
-
PNPase
Escherichia coli K-12 CA244, Escherichia coli MG1193
-
-
-
PNPase
Escherichia coli MG1655
-
;
-
PNPase
G8TCS8
-
PNPase
-
-
PNPase
O87792
-
polynucleotide phosphorylase
-
-
-
-
polynucleotide phosphorylase
-
-
polynucleotide phosphorylase
-
-
polynucleotide phosphorylase
Bacillus subtilis BG214
-
-
-
polynucleotide phosphorylase
-
-
polynucleotide phosphorylase
-
-
polynucleotide phosphorylase
Caulobacter vibrioides NA1000
-
-
-
polynucleotide phosphorylase
-
-
polynucleotide phosphorylase
A5EXU0
-
polynucleotide phosphorylase
-
-
polynucleotide phosphorylase
A7ZS61
-
polynucleotide phosphorylase
P05055
-
polynucleotide phosphorylase
Escherichia coli JM83
-
-
-
polynucleotide phosphorylase
-
-
polynucleotide phosphorylase
Escherichia coli K-12 CA244, Escherichia coli MG1193
-
-
-
polynucleotide phosphorylase
Escherichia coli MG1655
-
;
-
polynucleotide phosphorylase
-
-
polynucleotide phosphorylase
G8TCS8
-
polynucleotide phosphorylase
-
-
polynucleotide phosphorylase
-
-
polynucleotide phosphorylase
O87792
-
polyribonucleotide phosphorylase
-
-
-
-
RNase PH
Arabidopsis thaliana Col-0.
-
-
-
CAS REGISTRY NUMBER
COMMENTARY
9014-12-4
-
ORGANISM
COMMENTARY
LITERATURE
SEQUENCE CODE
SEQUENCE DB
SOURCE
KR. 170-4
-
-
Manually annotated by BRENDA team
Achromobacter sp. KR. 170-4
KR. 170-4
-
-
Manually annotated by BRENDA team
Arabidopsis thaliana Col-0.
-
-
-
Manually annotated by BRENDA team
Bacillus amyloliquefaciens BaM-2
BaM-2
-
-
Manually annotated by BRENDA team
strain BG214
-
-
Manually annotated by BRENDA team
Bacillus subtilis BG214
strain BG214
-
-
Manually annotated by BRENDA team
calf
-
-
Manually annotated by BRENDA team
Brevibacterium sp. JM 98A
JM 98A
-
-
Manually annotated by BRENDA team
strains 81-176 and F38011
-
-
Manually annotated by BRENDA team
strains F38011 and 81-176
-
-
Manually annotated by BRENDA team
Caulobacter vibrioides NA1000
gene pnp
-
-
Manually annotated by BRENDA team
; strain JM83
-
-
Manually annotated by BRENDA team
and several other genotypes of bacterial strains used
SwissProt
Manually annotated by BRENDA team
PNPase is one of the cold shock-induced proteins in Escherichia coli, pnp gene encoding PNPase is essential for growth at low temperatures
-
-
Manually annotated by BRENDA team
specific sites in the 5-untranslated region of enzyme mRNA are required for enzyme-sensitive cold-inducued suppression of Rho-dependent transcription termination
-
-
Manually annotated by BRENDA team
strain MG1693
-
-
Manually annotated by BRENDA team
Escherichia coli JM83
strain JM83
-
-
Manually annotated by BRENDA team
strain CA244
-
-
Manually annotated by BRENDA team
Escherichia coli K-12 CA244
strain CA244
-
-
Manually annotated by BRENDA team
Escherichia coli MG1193
gene pnp
-
-
Manually annotated by BRENDA team
Escherichia coli MG1655
-
-
-
Manually annotated by BRENDA team
Escherichia coli MG1655
gene pnp
-
-
Manually annotated by BRENDA team
Escherichia coli MG1693
strain MG1693
-
-
Manually annotated by BRENDA team
recombinant enzyme
-
-
Manually annotated by BRENDA team
a primer-independent, i.e. form I enzyme, and a primer-dependent, i.e. form T enzyme
-
-
Manually annotated by BRENDA team
L. var Samsun, healthy and TMV-infected leaves
-
-
Manually annotated by BRENDA team
tobacco mosaic virus-infected
-
-
Manually annotated by BRENDA team
MAC
-
-
Manually annotated by BRENDA team
strain KT2440, gene pnp
SwissProt
Manually annotated by BRENDA team
photosynthetic bacterium
-
-
Manually annotated by BRENDA team
strain F-28
-
-
Manually annotated by BRENDA team
Sinorhizobium meliloti F-28
strain F-28
-
-
Manually annotated by BRENDA team
HB-8 strain
-
-
Manually annotated by BRENDA team
Thermus thermophilus HB-8
HB-8 strain
-
-
Manually annotated by BRENDA team
GENERAL INFORMATION
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
evolution
-
polynucleotide phosphorylase is a conserved, widely distributed phosphorolytic 3'-5' exoribonuclease
evolution
-
human polynucleotide phosphorylase is an evolutionary conserved RNA-processing enzyme. PNPase contains five motifs that are conspicuously preserved through evolution extending from prokaryotes and plants to mammals. Although hPNPase structurally and biochemically resembles PNPase of other species, overexpression and inhibition studies reveal that hPNPase has evolved to serve more specialized and diversified functions in humans
evolution
-
two domains, both resembling closely the phosphorolytic exoribonuclease RNase PH, EC 27.7.56, almost certainly have originated from duplication and fusion of an ancestral gene. While the C-terminal RNase PH-like domain catalyses phosphorolytic attack of RNA, the N-terminal domain has lost this capacity. Instead, it contributes to the ring-like quaternary structure of the trimeric PNPase assembly
evolution
Caulobacter vibrioides NA1000
-
two domains, both resembling closely the phosphorolytic exoribonuclease RNase PH, EC 27.7.56, almost certainly have originated from duplication and fusion of an ancestral gene. While the C-terminal RNase PH-like domain catalyses phosphorolytic attack of RNA, the N-terminal domain has lost this capacity. Instead, it contributes to the ring-like quaternary structure of the trimeric PNPase assembly
-
malfunction
-
PNPase-deficient mutant is hypersensitive to oxidative challenges
malfunction
-
deletion of the pnp gene, encoding polynucleotide phosphorylase, results in increased biofilm formation in Escherichia coli
malfunction
-
the inactivation of the pnp gene reduces significantly the ability of Campylobacter jejuni to adhere and to invade Ht-29 cells, the mutant strain exhibits a decrease in swimming ability and chick colonization, 81-176 phenotype, overview. The pnp mutation do not induce profound proteomic changes suggesting that other ribonucleases in the organism might ensure this biological function in the absence of PNPase
malfunction
-
spontaneous mutations resulting from replication errors, which are normally repaired by the mismatch repair system, are sharply reduced in a polynucleotide phosphorylase-deficient Escherichia coli strain
malfunction
-
in a liver mitochondria from a liver-specific PNPase knockout mouse model, the decrease in functional electron transport chain complexes is responsible for decreased respiration. Liver mitochondria from liver-specific knockout mice display disordered circular and smooth inner membrane criste, similar to mitochondria having impaired components of oxidative phosphorylation pathways. Citrate synthase activity, routinely used as a marker of aerobic capacity, also decreases in the liver of PNPase knockout mice compared with the wild-type mice
malfunction
-
enzyme depletion decreases splicing efficiency and inhibits intron degradation, effects on intron metabolism, overview. In mutants lacking cpPNPase activity, unusual RNA patterns occur, intron-containing fragments also accumulate in mutants. Mutants show gene-dependent and intermediate RNA phenotypes, suggesting that reduced enzyme activity differentially affects chloroplast transcripts
malfunction
-
inhibition of the enzyme by shRNA or stable overexpression of miR-221 protects melanoma cells from IFN-beta-mediated growth inhibition
malfunction
-
loss-of-function mutations in pnp result in a decreased stability of several sRNAs including RyhB, SgrS, and CyaR and also decrease both the negative and positive regulation by sRNAs. The defect in stability of CyaR and in negative and positive regulation are suppressed by deletion mutations in RNase E. Lack of sRNA-mediated regulation in the absence of an active form of PNPase is due to the rapid turnover of sRNA resulting from an increase in RNase E activity and/or an increase in access of other ribonucleases to sRNAs. The defect in sRNA regulation caused by the pnp mutations is independent of Hfq. While Hfq does not appear to be limiting, it seems possible that lack of PNPase leads to inactivation of Hfq
malfunction
Arabidopsis thaliana Col-0.
-
enzyme depletion decreases splicing efficiency and inhibits intron degradation, effects on intron metabolism, overview. In mutants lacking cpPNPase activity, unusual RNA patterns occur, intron-containing fragments also accumulate in mutants. Mutants show gene-dependent and intermediate RNA phenotypes, suggesting that reduced enzyme activity differentially affects chloroplast transcripts
-
malfunction
Escherichia coli K-12 CA244
-
PNPase-deficient mutant is hypersensitive to oxidative challenges
-
malfunction
Escherichia coli MG1193
-
loss-of-function mutations in pnp result in a decreased stability of several sRNAs including RyhB, SgrS, and CyaR and also decrease both the negative and positive regulation by sRNAs. The defect in stability of CyaR and in negative and positive regulation are suppressed by deletion mutations in RNase E. Lack of sRNA-mediated regulation in the absence of an active form of PNPase is due to the rapid turnover of sRNA resulting from an increase in RNase E activity and/or an increase in access of other ribonucleases to sRNAs. The defect in sRNA regulation caused by the pnp mutations is independent of Hfq. While Hfq does not appear to be limiting, it seems possible that lack of PNPase leads to inactivation of Hfq
-
malfunction
Escherichia coli MG1655
-
deletion of the pnp gene, encoding polynucleotide phosphorylase, results in increased biofilm formation in Escherichia coli
-
metabolism
-
PNPase, together with the endonuclease RNase E, the DEAD-box RNA helicase RhlB, and enolase, constitutes the RNA degradosome, a multiprotein machine devoted to RNA degradation
metabolism
-
the Krebs cycle metabolite citrate affects the activity of Escherichia coli polynucleotide phosphorylase (PNPase) and, conversely, that cellular metabolism is affected widely by PNPase activity, a PNPase-mediated response to citrate, and PNPase deletion broadly impacts on the metabolome and on global gene expression, detailed overview
metabolism
-
the enzyme is involved in RNA degradation and/turnover, major processes controlling RNA levels and important regulators of physiological and pathological processes
physiological function
A7ZS61
PNPase is a processive exoribonuclease that contributes to messenger RNA turnover and quality control of ribosomal RNA precursors
physiological function
-
PNPase plays a role of in low-temperature survival of Campylobacter jejuni
physiological function
-
PNPase primarily functions in exonucleolytic degradation of RNA in the 3'->5' direction, PNPase also functions in minimizing oxidized RNA in vivo
physiological function
A5EXU0, -
PNPase is a virulence repressor in benign strains of Dichelobacter nodosus
physiological function
-
Bacillus subtilis polynucleotide phosphorylase 3'-to-5' DNase activity is involved in DNA repair
physiological function
-
PNPase may be solely responsible for chloroplast polyadenylation activity
physiological function
-
PNPase regulates chloroplast transcript accumulation in response to phosphorus starvation, the activity of the chloroplast PNPase is involved in plant acclimation to phosphorus availability and may help maintain an appropriate balance of phosphorus metabolites even under normal growth conditions
physiological function
-
polynucleotide phosphorylase is an RNA processing enzyme and a component of the RNA degradosome. It plays an important role in RNA processing and turnover, being implicated in RNA degradation and in polymerization of heteropolymeric tails at the 3'-end of mRNA. PNPase is necessary to maintain bacterial cells in the planktonic mode through downregulation of pgaABCD expression and poly-N-acetylglucosamine production. But the pnp gene is not essential. Negative regulation of the poly-N-acetylglucosamine biosynthetic operon pgaABCD by PNPase
physiological function
-
the role of PNPase is pleiotropic
physiological function
-
polynucleotide phosphorylase plays a central role in RNA degradation, generating a pool of ribonucleoside diphosphates that can be converted to deoxyribonucleoside diphosphates by ribonucleotide reductase
physiological function
-
metabolite-bound PNPase structure and evidence for an allosteric pocket, overview
physiological function
G8TCS8
human polynucleotide phosphorylase is a 3'-to-5' exoribonuclease that degrades specific mRNA and miRNA, and imports RNA into mitochondria, and thus regulates diverse physiological processes, including cellular senescence and homeostasis
physiological function
-
polynucleotide phosphorylase is an RNA-processing enzyme with expanding roles in regulating cellular physiology. By executing exonuclease activity PNPase specifically degrades mature miRNAs, schematic model of microRNA biogenesis and stability, overview. The enzyme might have an essential role in senescence- and differentiation-associated growth inhibition, involvement of hPNPase in producing pathological changes associated with aging by generating pro-inflammatory cytokines via reactive oxygen species and NF-kappaB, growth inhibition in different cancer cells and its molecular mechanism, overview. Direct involvement of PNPase in regulating specific cytosolic RNA import into the mitochondrial matrix, independently of its RNA-processing function
physiological function
-
pivotal role of PNPase in mitochondrial morphogenesis and respiration in vivo
physiological function
-
polynucleotide phosphorylase is an exoribonuclease that cleaves single-stranded RNA substrates with 3' -5' directionality and processive behaviour
physiological function
-
the chloroplastidic enzyme has a major role in maturing mRNA and rRNA 3'-ends, but also participates in RNA degradation through exonucleolytic digestion and polyadenylation.Cchloroplast PNPase and a poly(A) polymerase share the polymerization role in wild-type plants. Chloroplast PNPase appears to be required for a degradation step following endonucleolytic cleavage of the excised lariat. The enzyme functions depend absolutely on the catalytic site within the second duplicated RNase PH domain, and appear to be modulated by the first RNase PH domain, but both PNPase domains contribute to chloroplast rRNA and mRNA processing, overview
physiological function
-
hPNPaseold-35 regulates the expression of specific miRNAs, importance of hPNPaseold-35 induction and miR-221 downregulation in mediating IFN-beta action, mechanism of miRNA regulation involving selective enzymatic degradation, overview
physiological function
Arabidopsis thaliana Col-0.
-
the chloroplastidic enzyme has a major role in maturing mRNA and rRNA 3'-ends, but also participates in RNA degradation through exonucleolytic digestion and polyadenylation.Cchloroplast PNPase and a poly(A) polymerase share the polymerization role in wild-type plants. Chloroplast PNPase appears to be required for a degradation step following endonucleolytic cleavage of the excised lariat. The enzyme functions depend absolutely on the catalytic site within the second duplicated RNase PH domain, and appear to be modulated by the first RNase PH domain, but both PNPase domains contribute to chloroplast rRNA and mRNA processing, overview
-
physiological function
Bacillus subtilis BG214
-
Bacillus subtilis polynucleotide phosphorylase 3'-to-5' DNase activity is involved in DNA repair
-
physiological function
Caulobacter vibrioides NA1000
-
polynucleotide phosphorylase is an exoribonuclease that cleaves single-stranded RNA substrates with 3' -5' directionality and processive behaviour
-
physiological function
Escherichia coli K-12 CA244
-
PNPase primarily functions in exonucleolytic degradation of RNA in the 3'->5' direction, PNPase also functions in minimizing oxidized RNA in vivo
-
physiological function
Escherichia coli MG1655
-
metabolite-bound PNPase structure and evidence for an allosteric pocket, overview; polynucleotide phosphorylase is an RNA processing enzyme and a component of the RNA degradosome. It plays an important role in RNA processing and turnover, being implicated in RNA degradation and in polymerization of heteropolymeric tails at the 3'-end of mRNA. PNPase is necessary to maintain bacterial cells in the planktonic mode through downregulation of pgaABCD expression and poly-N-acetylglucosamine production. But the pnp gene is not essential. Negative regulation of the poly-N-acetylglucosamine biosynthetic operon pgaABCD by PNPase
-
metabolism
Escherichia coli MG1655
-
PNPase, together with the endonuclease RNase E, the DEAD-box RNA helicase RhlB, and enolase, constitutes the RNA degradosome, a multiprotein machine devoted to RNA degradation; the Krebs cycle metabolite citrate affects the activity of Escherichia coli polynucleotide phosphorylase (PNPase) and, conversely, that cellular metabolism is affected widely by PNPase activity, a PNPase-mediated response to citrate, and PNPase deletion broadly impacts on the metabolome and on global gene expression, detailed overview
-
additional information
-
the increase in the rNDP pools generated by polynucleotide phosphorylase degradation of RNA is responsible for the spontaneous mutations observed in an mismatch repair-deficient background, and is also responsible for the observed mutations in the mutT mutator background and those that occur after treatment with 5-bromodeoxyuridine
additional information
-
the S1 and KH domains of polynucleotide phosphorylase determine the efficiency of RNA binding and enzyme autoregulation, modeling of the roles of the KH and S1 domains in PNPase-RNA interactions and in substrate binding, overview
additional information
G8TCS8
the C-terminal S1 domain is not critical for RNA binding, and conversely, the conserved GXXG motif in the KH domain directly participates in RNA binding in hPNPase. The enzyme uses a KH pore to trap a long RNA 3' tail that is further delivered into an RNase PH channel for the degradation process. The three KH domains form a KH pore situated on the top of the hexameric ring-like structure. The KH pore extends the central channel formed by the RNase PH domains and is involved in the binding of RNA substrates, which are further delivered to the active site located within the central channel. Structural RNA with short 3' tails are, on the other hand, transported but not digested by hPNPase. Structural model of hPNPase, overview
additional information
-
two conserved catalytic RNase PH regions, a small domain of about 250 amino acid residues involved primarily in the 3' processing of transfer RNA precursors, are present at the N-terminus of the human enzyme. The RNA-binding property of hPNPase is conferred by two C-terminal RNA-binding domains, KH and S1
additional information
-
the enzyme has a ring-like, trimeric architecture that creates a central channel where phosphorolytic active sites reside, with asymmetry within the catalytic core of the enzyme. One face of the ring is decorated with RNA-binding K-homology (KH) and S1 domains. In the RNA-free form, the S1 domains adopt a splayed conformation that may facilitate capture of RNA substrates. In the RNA-bound structure, the three KH domains collectively close upon the RNA and direct the 3' end towards a constricted aperture at the entrance of the central channel. Structural non-equivalence, induced upon RNA binding, helps to channel substrate to the active sites through mechanical ratcheting. Access to the PNPase active sites is through the central channel, which can accommodate single-stranded RNA with some structural adjustment of a constricted aperture at the channel entrance, residues and motifs involved in RNA directionality, recognition, and quarternary changes in the core, structure-function-relationship, detailed overview
additional information
-
also see for EC 2.7.7.56. RNase PH, EC 2.7.7.8, consists of tandem N-terminal RNase PH-like segments, known as core domains, as well as KH and S1 RNA-binding domains. The conserved residue D625 is located in the catalytic site and functions in phosphorolysis
additional information
-
human melanoma cells infected with an adenovirus expressing hPNPaseold-35 and are used for identification of miRNAs differentially and specifically regulated by hPNPaseold-35. Overexpression of miR-221 in HO-1 cells confers resistance to IFN-beta-mediated growth arrest
additional information
Arabidopsis thaliana Col-0.
-
also see for EC 2.7.7.56. RNase PH, EC 2.7.7.8, consists of tandem N-terminal RNase PH-like segments, known as core domains, as well as KH and S1 RNA-binding domains. The conserved residue D625 is located in the catalytic site and functions in phosphorolysis
-
additional information
Caulobacter vibrioides NA1000
-
the enzyme has a ring-like, trimeric architecture that creates a central channel where phosphorolytic active sites reside, with asymmetry within the catalytic core of the enzyme. One face of the ring is decorated with RNA-binding K-homology (KH) and S1 domains. In the RNA-free form, the S1 domains adopt a splayed conformation that may facilitate capture of RNA substrates. In the RNA-bound structure, the three KH domains collectively close upon the RNA and direct the 3' end towards a constricted aperture at the entrance of the central channel. Structural non-equivalence, induced upon RNA binding, helps to channel substrate to the active sites through mechanical ratcheting. Access to the PNPase active sites is through the central channel, which can accommodate single-stranded RNA with some structural adjustment of a constricted aperture at the channel entrance, residues and motifs involved in RNA directionality, recognition, and quarternary changes in the core, structure-function-relationship, detailed overview
-
SUBSTRATE
PRODUCT                      
REACTION DIAGRAM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
24-nucleotide RNA molecule + ADP
25-nucleotide RNA molecule + phosphate
show the reaction diagram
-
when both ADP and phosphate are present at the reaction mixture, the direction of activity, either polyadenylation or degradation, is dependent on their relative concentrations
-
-
r
24-nucleotide RNA molecule + phosphate
23-nucleotide RNA molecule + nucleoside diphosphate
show the reaction diagram
-
when both ADP and phosphate are present at the reaction mixture, the direction of activity, either polyadenylation or degradation, is dependent on their relative concentrations
-
-
r
microR-221 RNAn+1 + phosphate
microR-221 RNAn + ADP
show the reaction diagram
-
recombinantly expressed microRNAs miR-let7a, miR-106b, miR-25, miR-221, miR-222, and miR-184 as substrates, the recombinant enzyme selectively and preferentially degrades microRNA-221 in human melanoma cells
-
-
r
pJFD4 HpaI RNA+1 + phosphate
pJFD4 HpaI RNA + nucleoside diphosphate
show the reaction diagram
-
derivative of SP82 phage RNA, arsenate can replace phosphate
-
?
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
-
?
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
A5EXU0, -
-
-
-
?
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
32% of activity with poly(U) in phosphorolysis reaction
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
no phosphorolysis actvity with poly(G)
-
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
poly(A) polymerization product containing 8000-13000 nucleotides
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
chloroplast PNPase has both exonuclease and poly(A) polymerase activity, phosphate enhances RNA degradation activity, ADP inhibits degradation and enhances poly(A) polymerization, ADP best substrate
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
strong preference for ADP and poly(A) in phosphorolysis and polymerization reaction
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
primer required for polymerization
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
Bacillus amyloliquefaciens BaM-2
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
Thermus thermophilus HB-8
-
primer required for polymerization
-
r
poly(A) + ADP
poly(A)+1 + phosphate
show the reaction diagram
Brevibacterium sp. JM 98A
-
-
no phosphorolysis actvity with poly(G)
-
poly(A)+1 + phosphate
poly(A) + ADP
show the reaction diagram
-
-
-
r
poly(A)+1 + phosphate
poly(A) + ADP
show the reaction diagram
-
-
-
ir
poly(A)+1 + phosphate
poly(A) + ADP
show the reaction diagram
-
-
-
r
poly(A)+1 + phosphate
poly(A) + ADP
show the reaction diagram
-
-
-
r
poly(C) + CDP
poly(C)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(C) + CDP
poly(C)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(C) + CDP
poly(C)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(C) + CDP
poly(C)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(C) + CDP
poly(C)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(C) + CDP
poly(C)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(C) + CDP
poly(C)+1 + phosphate
show the reaction diagram
-
-
low poly(C) phosphorolysis activity
r
poly(C) + CDP
poly(C)+1 + phosphate
show the reaction diagram
-
primer required for polymerization
-
r
poly(C) + CDP
poly(C)+1 + phosphate
show the reaction diagram
-
51% of activity with ADP
21% of activity with poly(U) in phosphorolysis reaction
r
poly(C) + CDP
poly(C)+1 + phosphate
show the reaction diagram
Thermus thermophilus HB-8
-
primer required for polymerization
-
r
poly(C)+1 + phosphate
poly(C) + ADP
show the reaction diagram
-
-
-
ir
poly(C)+1 + phosphate
poly(C) + ADP
show the reaction diagram
-
-
-
r
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
very little activity
-
r
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
primer required for polymerization
-
r
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
10% of activity with ADP and poly(A)
less than 15% of phosphorolysis activity with poly(A)
r
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
much lower activity than with ADP, activity depends on polyribonucleotide primer
-
-
-
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
-
GDP second best substrate
-
-
-
poly(G) + GDP
poly(G)+1 + phosphate
show the reaction diagram
Bacillus amyloliquefaciens BaM-2
-
-
-
r
poly(I) + IDP
poly(I)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(I) + IDP
poly(I)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(I) + IDP
poly(I)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(I) + IDP
poly(I)+1 + phosphate
show the reaction diagram
-
-
-
-
poly(I) + IDP
poly(I)+1 + phosphate
show the reaction diagram
-
-
phosphorolysis at 14% of activity with poly(A)
-
poly(I) + IDP
poly(I)+1 + phosphate
show the reaction diagram
-
primer required for polymerization
-
r
poly(I) + IDP
poly(I)+1 + phosphate
show the reaction diagram
-
48% of activity with ADP
28% of activity with poly(U) in phosphorolysis reaction
r
poly(U)+ UDP
poly(U)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(U)+ UDP
poly(U)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(U)+ UDP
poly(U)+1 + phosphate
show the reaction diagram
-
-
-
r
poly(U)+ UDP
poly(U)+1 + phosphate
show the reaction diagram
-
-
lower activity than with poly(A)
r
poly(U)+ UDP
poly(U)+1 + phosphate
show the reaction diagram
-
primer required for polymerization
-
r
poly(U)+ UDP
poly(U)+1 + phosphate
show the reaction diagram
-
55% of activity with ADP, best substrate for phosphorolysis reaction
-
r
poly(U)+ UDP
poly(U)+1 + phosphate
show the reaction diagram
Thermus thermophilus HB-8
-
primer required for polymerization
-
r
poly(U)+1 + phosphate
poly(U) + ADP
show the reaction diagram
-
-
-
ir
poly(U)+1 + phosphate
poly(U) + ADP
show the reaction diagram
-
-
-
r
poly(U)+1 + phosphate
poly(U) + ADP
show the reaction diagram
-
-
-
r
rabbit globin mRNAn+1 + phosphate
ADP + rabbit globin mRNAn
show the reaction diagram
-
only the poly(A) tail of the mRNA is removed
-
?
ribonucleoside 5'-diphosphate + phosphate
ribonucleoside 5'-diphosphate + phosphate
show the reaction diagram
-
-
exchange reaction
?
ribonucleoside 5'-diphosphate + phosphate
ribonucleoside 5'-diphosphate + phosphate
show the reaction diagram
-
-
exchange reaction
?
ribonucleoside 5'-diphosphate + phosphate
ribonucleoside 5'-diphosphate + phosphate
show the reaction diagram
-
-
exchange reaction
?
ribonucleoside 5'-diphosphate + phosphate
ribonucleoside 5'-diphosphate + phosphate
show the reaction diagram
-
-
exchange reaction
?
ribonucleoside 5'-diphosphate + phosphate
ribonucleoside 5'-diphosphate + phosphate
show the reaction diagram
-
-
exchange reaction
?
ribonucleoside 5'-diphosphate + phosphate
ribonucleoside 5'-diphosphate + phosphate
show the reaction diagram
-
-
exchange reaction
?
ribonucleoside 5'-diphosphate + phosphate
ribonucleoside 5'-diphosphate + phosphate
show the reaction diagram
-
exchange reaction with ADP, CDP, UDP and GDP
exchange reaction
?
ribonucleoside 5'-diphosphate + phosphate
ribonucleoside 5'-diphosphate + phosphate
show the reaction diagram
-
ADP preferred substrate for exchange, little or no reaction occurs with other nucleoside diphosphates
exchange reaction
?
ribonucleoside 5'-diphosphate + phosphate
ribonucleoside 5'-diphosphate + phosphate
show the reaction diagram
-
catalyzes exchange between beta-phosphate of ADP and phosphate, but only in presence of either an oligoribonucleotide bearing an unidentified C-3'-hydroxyl group or of ADP
exchange reaction
-
?
ribonucleoside 5'-diphosphate + phosphate
ribonucleoside 5'-diphosphate + phosphate
show the reaction diagram
-
ADP, GDP and CDP are better substrates than UDP, IDP and deoxribonucloside diphosphates do not serve as substrate
exchange reaction
?
ribonucleoside 5'-diphosphate + phosphate
ribonucleoside 5'-diphosphate + phosphate
show the reaction diagram
Bacillus amyloliquefaciens BaM-2
-
-
exchange reaction
?
RNA + ATP
RNA+1 + diphosphate
show the reaction diagram
-
polymerization in the absence of phosphate
-
r
RNA + CTP
RNA+1 + diphosphate
show the reaction diagram
-
polymerization in the absence of phosphate
-
r
RNA + GTP
RNA+1 + diphosphate
show the reaction diagram
-
polymerization in the absence of phosphate
-
r
RNA + UTP
RNA+1 + diphosphate
show the reaction diagram
-
polymerization in the absence of phosphate
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
?
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
?
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
?
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
?
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
Q41370
-
-
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
A7ZS61
-
-
-
?
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
specificity overview
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
ADP, GDP and CTP are better substrates than IDP and UDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
arsenolysis of poly(A), poly(C), poly(U) and poly(G)
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
activity in the absence of a primer, polymerization is stimulated by various polyribonucleotides or RNAs
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
primer-independent activity
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
primer-independent activity
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of IDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of IDP
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of IDP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of IDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of IDP
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of IDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of IDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of CDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of CDP
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of CDP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of CDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of CDP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of CDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of CDP
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of CDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of CDP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of CDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
synthesis of poly(A): no primer addition required if large amounts of enzyme or Mg2+ are used, with small amounts of either component a primer is required, poly(G) synthesis: primer required
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
synthetic activity enhanced in presence of a primer
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of GDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of GDP
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of GDP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of GDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of GDP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of GDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of GDP
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of GDP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of GDP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of GDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of GDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of GDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
ADP best substrate, UDP 55%, CDP 51%, IDP 48% of activity with ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
catalyzes addition of a single dAMP from dADP onto an oligoribonucleotide, further addition of either dAMP or AMP to (Ap)ndA is very difficult
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
ATP-phosphate exchange at one-third the rate observed with ADP
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
primer-dependent activity
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
primer-dependent activity
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
primer-dependent activity
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of UDP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of UDP
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of UDP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of UDP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of UDP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
primer independent enzyme
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
ADP, GDP, UDP and CDP polymerized to the extent of 7 S size polymer
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
de novo synthesis of polynucleotides, each of the 4 common ribonucleoside diphosphates can serve separately as a substrate for the polymerization reaction, leading to the formation of homopolymers, polymerization of a mixture of nucleoside diphosphates containing different bases results in the formation of a random copolymer, the enzyme does not require a template and cannot copy one, elongation of a primer oligonucleotide with at least 2 nucleoside residues and a free 3'-terminal hydroxyl group, in the reverse reaction breakdown of polyribonucleotides by phosphorolytic cleavage of the internucleotide bonds
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
de novo synthesis of polynucleotides, each of the 4 common ribonucleoside diphosphates can serve separately as a substrate for the polymerization reaction, leading to the formation of homopolymers, polymerization of a mixture of nucleoside diphosphates containing different bases results in the formation of a random copolymer, the enzyme does not require a template and cannot copy one, elongation of a primer oligonucleotide with at least 2 nucleoside residues and a free 3'-terminal hydroxyl group, in the reverse reaction breakdown of polyribonucleotides by phosphorolytic cleavage of the internucleotide bonds
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
de novo synthesis of polynucleotides, each of the 4 common ribonucleoside diphosphates can serve separately as a substrate for the polymerization reaction, leading to the formation of homopolymers, polymerization of a mixture of nucleoside diphosphates containing different bases results in the formation of a random copolymer, the enzyme does not require a template and cannot copy one, elongation of a primer oligonucleotide with at least 2 nucleoside residues and a free 3'-terminal hydroxyl group, in the reverse reaction breakdown of polyribonucleotides by phosphorolytic cleavage of the internucleotide bonds
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
de novo synthesis of polynucleotides, each of the 4 common ribonucleoside diphosphates can serve separately as a substrate for the polymerization reaction, leading to the formation of homopolymers, polymerization of a mixture of nucleoside diphosphates containing different bases results in the formation of a random copolymer, the enzyme does not require a template and cannot copy one, elongation of a primer oligonucleotide with at least 2 nucleoside residues and a free 3'-terminal hydroxyl group, in the reverse reaction breakdown of polyribonucleotides by phosphorolytic cleavage of the internucleotide bonds
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
de novo synthesis of polynucleotides, each of the 4 common ribonucleoside diphosphates can serve separately as a substrate for the polymerization reaction, leading to the formation of homopolymers, polymerization of a mixture of nucleoside diphosphates containing different bases results in the formation of a random copolymer, the enzyme does not require a template and cannot copy one, elongation of a primer oligonucleotide with at least 2 nucleoside residues and a free 3'-terminal hydroxyl group, in the reverse reaction breakdown of polyribonucleotides by phosphorolytic cleavage of the internucleotide bonds
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
strong preference for ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
copolymerization of ADP and dADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
purified enzyme is less dependent on a primer than the enzyme in crude extracts
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
either in the form of a homotrimeric enzyme or associated in a multiprotein complex, the degradosome, PNPase is involved in RNA processing
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase and RNAse II play an essential role in degrading fragments of mRNA generated by prior cleavage by endonucleases
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
chloroplast PNPase is most probably responsible for polyadenylation of RNA
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase is involved in tRNA degradation, PNPase is required for efficient 3'-end processing of mRNAs in vivo, but is not sufficient to mediate their degradation, PNPase may function as poly(A) mRNA 3'-5' degrading exonuclease in vivo
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase accounts for 10% of total mRNA decay, PNPase can bind double stranded DNA, however the affinity is lower than that obtained for both RNA and single stranded DNA binding
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase synthesizes long, highly heteropolymeric poly(A) tails in vivo and accounts for all of the residual polyadenylylation in poly(A) polymerase deficient strains, in addition PNPase is responsible for adding the C and U residues that are found in poly(A) tails in exponentially growing wild-type cultures
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase exonuclease activity plays an essential role in tRNA, mRNA and ribosome metabolism
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase is involved in RNA degradation
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase specifically binds to 8-oxoguanine-containing RNA, it is suggested that PNPase discriminate between oxidized and normal RNA which my contribute to a high fidelity of translation
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
Bacillus amyloliquefaciens BaM-2
-
polymerization of GDP, polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
primer-independent activity, polymerization of UDP, polymerization of ADP, purified enzyme is less dependent on a primer than the enzyme in crude extracts
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
Bacillus subtilis BG214
-
-
-
-
?
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
Thermus thermophilus HB-8
-
primer-dependent activity, ADP, GDP, UDP and CDP polymerized to the extent of 7 S size polymer
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
Sinorhizobium meliloti F-28
-
polymerization of CDP, polymerization of GDP, ADP best substrate, UDP 55%, CDP 51%, IDP 48% of activity with ADP, polymerization of UDP, polymerization of ADP
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
Brevibacterium sp. JM 98A
-
arsenolysis of poly(A), poly(C), poly(U) and poly(G)
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
Achromobacter sp. KR. 170-4
-
specificity overview, polymerization of IDP, polymerization of CDP, polymerization of GDP, polymerization of ADP
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
-
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
ir
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
-
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
ir
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
phosphorolysis of poly(U)
-
ir
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
phosphorolysis of poly(U)
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
phosphorolysis of poly(U)
-
-
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
poly(A), poly(U) and poly(C) most effective substrates
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
poly(U) best substrate, yeast RNA 2%, poly(A) 32%, poly(I) 28%, poly(C) 21% of the activity with poly(U)
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
phosphorolysis of poly(I)
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
phosphorolysis of poly(I)
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
strong preference for poly(A)
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
PNPase prefers degradation of polyadenylated and polyuridinylated RNAs due to the high binding affinities for poly(A) and poly(U), no activity with polyguanylated RNA
-
-
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
processive phosphorolysis of the poly(A) tail of each globin mRNA chain
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
phosphorolysis of poly(A)
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
phosphorolysis of poly(A)
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
phosphorolysis of poly(C)
-
ir
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
phosphorolysis of poly(C)
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
phosphorolysis of RNA, enzyme has no nucleoside diphosphate-polymerization activity
-
ir
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
enhanced expression of hPNPase(old-35) via a replication-incompetent adenovirus (Ad.hPNPase(old-35)) in human melanoma cells and normal melanocytes results in a characteristic sensecence-like phenotype. Overexpression of hPNPase(old-35) results in increased production of ROS, leading to activation of the nuclear factor (NF)-kappaB pathway. Ad.hPNPase(old-35) infection promotes degradation of IkappaBalpha and nuclear translocation of NF-kappaB and markedly increased binding of the transcriptional activator p50/p65. Infection with (Ad.hPNPase(old-35)) enhances the production of interleukin-6 and interleukin-8, two classical NF-kappaB-responsive cytokines. hPNPase(old-35) might play a significant role in producing pathological changes associated with aging be generating proinflammatory cytokines via ROS and NF-kappaB
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
poly(A) length of human mitochondrial mRNAs is controlled by polyadenylation by poly(A) polymerase and deadenylation by polynucleotide phosphorylase. Polyadenylation is required for stability of mitochondrial mRNAs
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
required for multiple aspects of the 18S rRNA metabolism
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
PNPase enhances the ability of Yersinia pseudotuberculosis to withstand the killing activities of murine macrophages. PNPase is required for the optimal functioning of the Yersinia type three secretion system, an organelle that injects effector proteins directly into host cells. PNPase plays multifaceted roles in enhancing Yersinia survival in response to stressfull conditions
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
in addition to its degradative role, PNPase can also function as a polymerase, adding 3' tails to transcripts. The reverse of degradation is favored when nucleoside diphosphate rather than inorganic phosphate is present in excess
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
substrate is synthetic radiolabeled SL9A RNA
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
Escherichia coli MG1655
-
in addition to its degradative role, PNPase can also function as a polymerase, adding 3' tails to transcripts. The reverse of degradation is favored when nucleoside diphosphate rather than inorganic phosphate is present in excess
-
-
r
RNAn+1 + phosphate
RNAn + ADP
show the reaction diagram
-
-
-
-
r
RNAn+1 + phosphate
RNAn + ADP
show the reaction diagram
G8TCS8
the enzyme catalyzes the processive phosphorolysis of RNA by using an inorganic phosphate to cleave the phosphodiester linkage at the 3'-end of a RNA chain
-
-
?
RNAn+1 + phosphate
RNAn + ADP
show the reaction diagram
-
substrates used for the forward degradation reaction are poly(rA) 15-mer RNA and phosphate
substrates used for the reverse polymerization reaction are poly(rA) 15-mer RNA and ADP
-
r
RNAn+1 + phosphate
RNAn + ADP
show the reaction diagram
G8TCS8
the functional trimeric phosphorylase is capable of digesting single-stranded RNA to produce final products of about 4 nt in length
-
-
?
RNAn+1 + phosphate
RNAn + ADP
show the reaction diagram
Escherichia coli MG1655
-
substrates used for the forward degradation reaction are poly(rA) 15-mer RNA and phosphate
substrates used for the reverse polymerization reaction are poly(rA) 15-mer RNA and ADP
-
r
yeast RNA+1 + phosphate
yeast RNA + nucleoside diphosphate
show the reaction diagram
-
2% of activity with poly(U)
-
?
microRNAn+1 + phosphate
microRNAn + ADP
show the reaction diagram
-
recombinantly expressed microRNAs miR-let7a, miR-106b, miR-25, miR-221, miR-222, and miR-184
-
-
r
additional information
?
-
-
enzyme is involved in tuning the expression of virulence genes and bacterial fitness during infection
-
-
-
additional information
?
-
-
enzyme may play a role in excluding oxidized forms of RNA from the translation mechanism
-
-
-
additional information
?
-
-
suppression of Rho-dependent transcription termination within the enzyme gene and its restoration by enzyme protein is an autogenous regulation circuit that modulates enzyme gene expression during cold acclimation
-
-
-
additional information
?
-
O87792, -
PNPase is one of the main exonucleolytic activities involved in RNA turnover and is widely conserved, but PNPase does not seem to be essential for growth, if the organisms are not subjected to special conditions, such as low temperature, transcriptional regulation, overview
-
-
-
additional information
?
-
-
enzyme affects the expression and activity of the type III secretion system by distinct mechanisms. the RNA-binding subdomain S1-dependent effect on type III secretion system involves an RNA intermediate
-
-
-
additional information
?
-
-
polynucleotide phosphorylase is essential for growth at low temperatures, while polymerization activity is not essential. RNase PH domains 1 and 2 of polynucleotide phosphorylase are important for its cold shock function, suggesting that the RNase activity of the enzyme is critical for its essential function at low temperature. Its polymerization activity is dispensable in its cold shock function. The RNase R , which is cold inducible, cannot complement the cold shock function of PNPase
-
-
-
additional information
?
-
-
polynucleotide phosphorylase is involved in protecting cells and limiting damaged RNA under oxidative conditions
-
-
-
additional information
?
-
-
polyribonucleotide phosphorylase-mediated degradation is a major regulatory event controlling the levels of sRNAs, namely stationary phase regulators MicA and RybB, that are required for the accurate expression of outer membrane proteins. Degradation by PNPase surpasses the effect of endonucleolytic cleavages by RNase E. Polyribonucleotide phosphorylase is an important enzyme in the growth phase adaptation to stationary phase
-
-
-
additional information
?
-
P05055
regulates its own expression at the level of mRNA stability and translation
-
-
-
additional information
?
-
-
the apoptosis-inducing activity of polynucleotide phosphorylase is mediated by activation of double-stranded RNAdependent protein kinase. Activation of RNA-dependent protein kinase by polynucleotide phosphorylase precedes phosphorylation of eukaryotic initiation factor-2A and induction of growth arrest and DNA damage-inducible gene 153, GADD153, that culminates in the shutdown of protein synthesis and apoptosis. Activation of RNA-dependent protein kinase by polynucleotide phosphorylase also instigates down-regulation of the antiapoptotic protein Bcl-xL
-
-
-
additional information
?
-
Q9ZAE1
at the optimal temperature, polynucleotide phosphorylase completely destroys RNAs that possess even a very stable intramolecular secondary structure, but leaves intact RNAs whose 3' end is protected by chemical modification or by hybridization with a complementary oligonucleotide. This allows individual RNAs to be isolated from heterogeneous populations by degrading unprotected species. If oligonucleotide is hybridized to an internal RNA segment, the Tth polynucelotide phosphorylase stalls eight nucleotides downstream of that segment. This allows any arbitrary 5'-terminal fragment of RNA to be prepared with a precision similar to that of run-off transcription, but without the need for a restriction site
-
-
-
additional information
?
-
-
examination of phosphorolytic activity. Enzyme is able to digest a substrate with a 3' single-stranded tail as well as a substrate possessing a 3' stem-loop structure. Presence of nucleoside diphosphates has no effect on the phosphorolytic activity
-
-
-
additional information
?
-
-
examination of phosphorolytic activity. Enzyme is able to digest a substrate with a 3' single-stranded tail as well as a substrate possessing a 3' stem-loop structure. Presence of nucleoside diphosphates results in decrease of Km value for phosphorolytic activity
-
-
-
additional information
?
-
-
no activity with ATP nor the other NTPs, as well as mono phosphate nucleotides. Enzyme degrades polyadenylated and nonpolyadenylated RNA at similar rates
-
-
-
additional information
?
-
-
in the presence of Mn2+ and low-level inorganic phosphate, PNPase degrades single-stranded DNA, the limited end-processing of DNA is regulated by ATP and is inactive in the presence of Mg2+ or high-level inorganic phosphate
-
-
?
additional information
?
-
-
PNPase specifically binds a synthetic RNA containing the oxidative lesion 8-hydroxyguanine, PNPase binds to RNA molecules of natural sequence that are oxidatively damaged by treatment with hydrogen peroxide, PNPase binds oxidized RNA with higher affinity than untreated RNA of the same sequence
-
-
-
additional information
?
-
-
suppressor of Var1 3 and polynucleotide phosphorylase form a 330-kDa heteropentamer that is capable of efficiently degrading double-stranded RNA substrates in the presence of ATP, the hSUV3-PNPase complex prefers substrates containing a 3' overhang and degrades the RNA in a 3'-to-5' directionality
-
-
-
additional information
?
-
A7ZS61
under conditions of excess nucleoside diphosphate and low concentrations of phosphate, PNPase catalyses the reverse reaction to add 3' extensions to transcripts
-
-
-
additional information
?
-
-
PNPase, as a phosphorylase, incorporates phosphate and ADP in degradation and polymerization process, respectively. The specificity of the enzyme for the polymerization reaction is high for ADP, with much less activity for other nucleotide diphosphates and no activity for ATP or other nucleotide triphosphates. The human PNPase displays no preferential activity for polyadenylated RNA like bacterial or chloroplast PNPase
-
-
-
additional information
?
-
-
polynucleotide phosphorylase is an exoribonuclease
-
-
-
additional information
?
-
G8TCS8
full-length and DELTAS1 hPNPase cleave the poly(A)12 and poly(U)12 RNA with similar activities and DELTAS1 hPNPase cleaves ssRNA substrate almost as efficiently as full-length PNPase
-
-
-
additional information
?
-
-
human polynucleotide phosphorylase hPNPaseold-35 is a type I IFN-inducible 3'-5' exoribonuclease, which degrades specific mRNAs and small noncoding RNAs. miR-221, a regulator of the cyclin-dependent kinase inhibitor p27kip1, displays robust downregulation with ensuing up-regulation of p27kip1 by expression of hPNPaseold-35,which also occurs in multiple human melanoma cells upon IFN-beta treatment
-
-
-
additional information
?
-
-
in the cytoplasm, human enzyme, from adenoviral-mediated overexpression, can directly degrade c-myc mRNA by virtue of its 3'-5' exoribonuclease property, and this degradation is specific for c-myc as compared with other mRNAs, such as c-jun, glyceraldehyde 3-phosphate dehydrogenase or GADD 34. In melanoma cells, degradation of microR-221 by hPNPase is more profound compared with other miRNAs
-
-
-
additional information
?
-
Escherichia coli JM83
-
polynucleotide phosphorylase is essential for growth at low temperatures, while polymerization activity is not essential. RNase PH domains 1 and 2 of polynucleotide phosphorylase are important for its cold shock function, suggesting that the RNase activity of the enzyme is critical for its essential function at low temperature. Its polymerization activity is dispensable in its cold shock function. The RNase R , which is cold inducible, cannot complement the cold shock function of PNPase
-
-
-
additional information
?
-
Escherichia coli K-12 CA244
-
PNPase specifically binds a synthetic RNA containing the oxidative lesion 8-hydroxyguanine, PNPase binds to RNA molecules of natural sequence that are oxidatively damaged by treatment with hydrogen peroxide, PNPase binds oxidized RNA with higher affinity than untreated RNA of the same sequence
-
-
-
additional information
?
-
Bacillus subtilis BG214
-
in the presence of Mn2+ and low-level inorganic phosphate, PNPase degrades single-stranded DNA, the limited end-processing of DNA is regulated by ATP and is inactive in the presence of Mg2+ or high-level inorganic phosphate
-
-
?
additional information
?
-
Arabidopsis thaliana Col-0.
-
polynucleotide phosphorylase is an exoribonuclease
-
-
-
additional information
?
-
Escherichia coli MG1693
-
polyribonucleotide phosphorylase-mediated degradation is a major regulatory event controlling the levels of sRNAs, namely stationary phase regulators MicA and RybB, that are required for the accurate expression of outer membrane proteins. Degradation by PNPase surpasses the effect of endonucleolytic cleavages by RNase E. Polyribonucleotide phosphorylase is an important enzyme in the growth phase adaptation to stationary phase
-
-
-
NATURAL SUBSTRATES
NATURAL PRODUCTS
REACTION DIAGRAM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
-
-
-
?
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
either in the form of a homotrimeric enzyme or associated in a multiprotein complex, the degradosome, PNPase is involved in RNA processing
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase and RNAse II play an essential role in degrading fragments of mRNA generated by prior cleavage by endonucleases
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
chloroplast PNPase is most probably responsible for polyadenylation of RNA
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase is involved in tRNA degradation, PNPase is required for efficient 3'-end processing of mRNAs in vivo, but is not sufficient to mediate their degradation, PNPase may function as poly(A) mRNA 3'-5' degrading exonuclease in vivo
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase accounts for 10% of total mRNA decay, PNPase can bind double stranded DNA, however the affinity is lower than that obtained for both RNA and single stranded DNA binding
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase synthesizes long, highly heteropolymeric poly(A) tails in vivo and accounts for all of the residual polyadenylylation in poly(A) polymerase deficient strains, in addition PNPase is responsible for adding the C and U residues that are found in poly(A) tails in exponentially growing wild-type cultures
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase exonuclease activity plays an essential role in tRNA, mRNA and ribosome metabolism
-
-
-
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase is involved in RNA degradation
-
r
RNAn + a nucleoside diphosphate
RNAn+1 + phosphate
show the reaction diagram
-
PNPase specifically binds to 8-oxoguanine-containing RNA, it is suggested that PNPase discriminate between oxidized and normal RNA which my contribute to a high fidelity of translation
-
-
-
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
-
-
-
r
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
enhanced expression of hPNPase(old-35) via a replication-incompetent adenovirus (Ad.hPNPase(old-35)) in human melanoma cells and normal melanocytes results in a characteristic sensecence-like phenotype. Overexpression of hPNPase(old-35) results in increased production of ROS, leading to activation of the nuclear factor (NF)-kappaB pathway. Ad.hPNPase(old-35) infection promotes degradation of IkappaBalpha and nuclear translocation of NF-kappaB and markedly increased binding of the transcriptional activator p50/p65. Infection with (Ad.hPNPase(old-35)) enhances the production of interleukin-6 and interleukin-8, two classical NF-kappaB-responsive cytokines. hPNPase(old-35) might play a significant role in producing pathological changes associated with aging be generating proinflammatory cytokines via ROS and NF-kappaB
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
poly(A) length of human mitochondrial mRNAs is controlled by polyadenylation by poly(A) polymerase and deadenylation by polynucleotide phosphorylase. Polyadenylation is required for stability of mitochondrial mRNAs
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
required for multiple aspects of the 18S rRNA metabolism
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
-
in addition to its degradative role, PNPase can also function as a polymerase, adding 3' tails to transcripts. The reverse of degradation is favored when nucleoside diphosphate rather than inorganic phosphate is present in excess
-
-
r
RNAn+1 + phosphate
RNAn + ADP
show the reaction diagram
G8TCS8
the enzyme catalyzes the processive phosphorolysis of RNA by using an inorganic phosphate to cleave the phosphodiester linkage at the 3'-end of a RNA chain
-
-
?
RNAn+1 + phosphate
RNAn + a nucleoside diphosphate
show the reaction diagram
Escherichia coli MG1655
-
in addition to its degradative role, PNPase can also function as a polymerase, adding 3' tails to transcripts. The reverse of degradation is favored when nucleoside diphosphate rather than inorganic phosphate is present in excess
-
-
r
additional information
?
-
-
enzyme is involved in tuning the expression of virulence genes and bacterial fitness during infection
-
-
-
additional information
?
-
-
enzyme may play a role in excluding oxidized forms of RNA from the translation mechanism
-
-
-
additional information
?
-
-
suppression of Rho-dependent transcription termination within the enzyme gene and its restoration by enzyme protein is an autogenous regulation circuit that modulates enzyme gene expression during cold acclimation
-
-
-
additional information
?
-
O87792, -
PNPase is one of the main exonucleolytic activities involved in RNA turnover and is widely conserved, but PNPase does not seem to be essential for growth, if the organisms are not subjected to special conditions, such as low temperature, transcriptional regulation, overview
-
-
-
additional information
?
-
-
enzyme affects the expression and activity of the type III secretion system by distinct mechanisms. the RNA-binding subdomain S1-dependent effect on type III secretion system involves an RNA intermediate
-
-
-
additional information
?
-
-
polynucleotide phosphorylase is essential for growth at low temperatures, while polymerization activity is not essential. RNase PH domains 1 and 2 of polynucleotide phosphorylase are important for its cold shock function, suggesting that the RNase activity of the enzyme is critical for its essential function at low temperature. Its polymerization activity is dispensable in its cold shock function. The RNase R , which is cold inducible, cannot complement the cold shock function of PNPase
-
-
-
additional information
?
-
-
polynucleotide phosphorylase is involved in protecting cells and limiting damaged RNA under oxidative conditions
-
-
-
additional information
?
-
-
polyribonucleotide phosphorylase-mediated degradation is a major regulatory event controlling the levels of sRNAs, namely stationary phase regulators MicA and RybB, that are required for the accurate expression of outer membrane proteins. Degradation by PNPase surpasses the effect of endonucleolytic cleavages by RNase E. Polyribonucleotide phosphorylase is an important enzyme in the growth phase adaptation to stationary phase
-
-
-
additional information
?
-
P05055
regulates its own expression at the level of mRNA stability and translation
-
-
-
additional information
?
-
-
the apoptosis-inducing activity of polynucleotide phosphorylase is mediated by activation of double-stranded RNAdependent protein kinase. Activation of RNA-dependent protein kinase by polynucleotide phosphorylase precedes phosphorylation of eukaryotic initiation factor-2A and induction of growth arrest and DNA damage-inducible gene 153, GADD153, that culminates in the shutdown of protein synthesis and apoptosis. Activation of RNA-dependent protein kinase by polynucleotide phosphorylase also instigates down-regulation of the antiapoptotic protein Bcl-xL
-
-
-
additional information
?
-
-
PNPase, as a phosphorylase, incorporates phosphate and ADP in degradation and polymerization process, respectively. The specificity of the enzyme for the polymerization reaction is high for ADP, with much less activity for other nucleotide diphosphates and no activity for ATP or other nucleotide triphosphates. The human PNPase displays no preferential activity for polyadenylated RNA like bacterial or chloroplast PNPase
-
-
-
additional information
?
-
-
polynucleotide phosphorylase is an exoribonuclease
-
-
-
additional information
?
-
Escherichia coli JM83
-
polynucleotide phosphorylase is essential for growth at low temperatures, while polymerization activity is not essential. RNase PH domains 1 and 2 of polynucleotide phosphorylase are important for its cold shock function, suggesting that the RNase activity of the enzyme is critical for its essential function at low temperature. Its polymerization activity is dispensable in its cold shock function. The RNase R , which is cold inducible, cannot complement the cold shock function of PNPase
-
-
-
additional information
?
-
Arabidopsis thaliana Col-0.
-
polynucleotide phosphorylase is an exoribonuclease
-
-
-
additional information
?
-
Escherichia coli MG1693
-
polyribonucleotide phosphorylase-mediated degradation is a major regulatory event controlling the levels of sRNAs, namely stationary phase regulators MicA and RybB, that are required for the accurate expression of outer membrane proteins. Degradation by PNPase surpasses the effect of endonucleolytic cleavages by RNase E. Polyribonucleotide phosphorylase is an important enzyme in the growth phase adaptation to stationary phase
-
-
-
COFACTOR
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
AMP
-
stimulates polymerization of ADP
METALS and IONS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
Ca2+
-
no effect in E. coli enzyme, 0.005 mM, 3fold activation of Bacillus stearothermophilus enzyme
Ca2+
-
activity depends on divalent cation, efficiency in descending order: Mg2+, Mn2+, Co2+, Zn2+, Cu2+, Ca2+
Cd2+
-
stimulates
Co2+
-
stimulates
Co2+
-
activity depends on divalent cation, efficiency in descending order: Mg2+, Mn2+, Co2+, Zn2+, Cu2+, Ca2+
Cu2+
-
activity depends on divalent cation, efficiency in descending order: Mg2+, Mn2+, Co2+, Zn2+, Cu2+, Ca2+
K+
-
activates polymerization; potassium salts activate
K+
-
maximal activation at 200 mm
Lithium salts
-
activate
Mg2+
-
100000 Da form requires high Mg2+ concentrations; Km: 0.05 mM; required for activity
Mg2+
-
preferentially activated by Mg2+
Mg2+
-
optimal concentration for polymerization, phosphorolysis and ADP-phosphate exchange at 1 mM, 1-3 mM and 3 mM, respectively
Mg2+
-
optimal concentration for polymerization and phosphorolysis at 0.4 mM, optimum nucleotide/Mg2+ ratios for ADP, CDP and UDP are 4/1, 4/1 and 5/1, respectively; required for activity
Mg2+
-
divalent cation required, maximal activation at approx. 2 mM, Mg2+ is more effective than Mn2+ for polymerization, Mn2+ better activator in phosphorolytic reaction
Mg2+
-
Mg2+ or Mn2+ required for activity, maximal activation at 1 mM Mg2+, inhibition above
Mg2+
-
maximal activation at 6 mM; required for activity
Mg2+
-
required for activity
Mg2+
-
maximal activation of ADP and GDP polymerization at 10 and 5 mM, respectively, inhibition at higher concentrations; required for activity
Mg2+
-
activity depends on divalent cation, order of efficiency: Mg2+, Mn2+, Co2+, Zn2+, Cu2+, Ca2+
Mg2+
Q9ZAE1
required, enzyme retains significant activity when the concentration is in the micromolar range
Mg2+
A7ZS61
essential cofactor for PNPase catalysis
Mg2+
-
RNase activity of PNPase requires Mg2+
Mg2+
-
required
Mg2+
G8TCS8
required
Mn2+
-
can partially replace Mg2+ in activation; stimulates polymerization more efficiently than Mg2+
Mn2+
-
can partially replace Mg2+ in activation
Mn2+
-
200000 Da form requires Mn2+ for NDP polymerization, polymerization of GDP proceedes efficiently in presence of Mn2+ at 60C, polymerization with a mutant enzyme from E. coli Q13 requires Mn2+ rather than Mg2+; can partially replace Mg2+ in activation
Mn2+
-
optimal concentration for polymerization, phosphorolysis and ADP-phosphate exchange at 1 mM
Mn2+
-
20-30% of activity with Mg2+; can partially replace Mg2+ in activation; effective polymer:Mg2+ ratio is 1:1
Mn2+
-
divalent cation required, Mg2+ more effective than Mn2+ for polymerization, Mn2+ better activator in phosphorolytic reaction
Mn2+
-
Mg2+ or Mn2+ required for activity, maximal activation at 0.06 mM Mn2+, inhibition above
Mn2+
-
can partially replace Mg2+ in activation
Mn2+
-
7-9% of activity with Mg2+
Mn2+
-
can partially replace Mg2+ in activation
Mn2+
-
activity depends on divalent cation, efficiency in descending order: Mg2+, Mn2+, Co2+, Zn2+, Cu2+, Ca2+
Mn2+
A7ZS61
Mn2+ can substitute for Mg2+ as an essential co-factor for PNPase catalysis
Mn2+
-
in the presence of Mn2+ and low-level inorganic phosphate, PNPase degrades single-stranded DNA
Mn2+
-
manganese can substitute for magnesium as the catalytic metal in PNPase, and RNA degradation
Na+
-
activates polymerization; sodium salts activate
Na+
-
NaCl stimulates polymerization maximally at250 mM, inhibition above
Zn2+
-
activity depends on divalent cation, efficiency in descending order: Mg2+, Mn2+, Co2+, Zn2+, Cu2+, Ca2+
INHIBITORS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
Acridine orange
-
inhibition of polymerization
ADP
-
inhibits ADP-phosphate exchange
ATP
-
1.6 mM, 25% inhibition of ADP polymerization
ATP
-
5 mM, 28C, presence of MgCl2, 30% residual activity. Allosteric inhibition of both polymerization and phosphorolytic activities, mixed-type inhibition toward phosphate
beta,gamma-Imido-ATP
-
5 mM, 28C, presence of MgCl2, 50% residual activity
chlortetracycline
-
competitive inhibition of ADP polymerization
citrate
-
a PNPase-mediated response to citrate, and PNPase deletion broadly impacts on the metabolome. PNPase-dependent cells show reduced growth in the presence of increased citrate concentration. In vitro, citrate directly binds and modulates PNPase activity, and the enzyme is inhibited by binding of metal-chelated citrate, predominantly complexed as magnesium-citrate, in the active site at physiological concentrations. In the contrary, metal-free citrate is bound at a vestigial active site, where it stimulates PNPase activity
dADP
-
0.16 mM, more than 80% inhibition of ADP polymerization
dADP
-
competitive inhibition of de novo polymerization of ADP by primer-independent form I and primer-dependent form T
dATP
-
5 mM, 28C, presence of MgCl2, 39% residual activity
dGTP
-
5 mM, 28C, presence of MgCl2, 40% residual activity
GDP
-
0.8 mM, more than 80% inhibition of ADP polymerization
GTP
-
5 mM, 28C, presence of MgCl2, 65% residual activity
hydrogen peroxide
-
upon exposure of human cells, the amount of enzyme protein decreases rapidly
menadione
-
upon exposure of human cells, the amount of enzyme protein decreases rapidly
Na2HPO4
-
0.0032 mM, complete inhibition
NaCl
-
stimulates polymerization maximally at 250 mM, inhibition above
NaCl
-
almost complete inhibition of phosphorolysis and NDP-phosphate exchange reaction at approx. 150 mM
phosphate
-
inhibition of ADP-phosphate exchange
phosphate
-
0.5 mM, complete inhibition
phosphate
-
0.1 mM, complete inhibition of polymerization activity
phosphate
-
complete inhibition of polymerization at low concentrations
phosphate
-
inhibition of chloroplast PNPase polymerization activity
phosphate
-
inhibitory at about 10 mM
Poly(A)
-
inhibition of oligadenylate and oligouridylate phosphorolysis
Poly(A)
-
inhibition of poly(U) synthesis
Poly(A)
-
inhibition of poly(A) synthesis
Poly(G)
-
inhibition of poly(A) synthesis
Poly(G)
-
inhibition of exoribonuclease activity due to its formation of a strong tertiary structure
rifamycin SV
-
partial inhibition of polymerization
Sucrose
-
50%, approx. 50% inhibition of partially purified enzyme
synthetic polynucleotide
-
-
-
Mg2+
-
stimulates ADP polymerization maximally at 10 mM, GDP polymerization maximally at 5 mM, inhibition above
additional information
-
polymerization reaction is not inhibited by diphosphate
-
additional information
-
relatively insensitive to N-ethylmaleimide and high concentrations of KCl
-
additional information
-
no specific decrease in enzyme protein level upon treatment of cells with cycloheximide or ACNU, i.e. 1-(4-amino-2-methyl-5-pyrimidinyl) methyl-3-(2-chloroethyl)-3-nitrosurea hydrochloride
-
additional information
-
not inhibitory: CTP, UTP
-
ACTIVATING COMPOUND
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
AMP
-
1.6 mM, 30% activation of ADP polymerization
Basic polypeptide
-
peptide from Escherichia coli extract, enhances ADP-phosphate exchange
-
Bis-(3-aminopropyl)-amine
-
optimal polymerization activity requires presence, 2fold increase in activity at 30 mM
citrate
-
a PNPase-mediated response to citrate, and PNPase deletion broadly impacts on the metabolome. PNPase-dependent cells show reduced growth in the presence of increased citrate concentration. In vitro, citrate directly binds and modulates PNPase activity, and the enzyme is inhibited by binding of metal-chelated citrate, predominantly complexed as magnesium-citrate, in the active site at physiological concentrations. In the contrary, metal-free citrate is bound at a vestigial active site, where it stimulates PNPase activity, this vestigial site as an allosteric binding pocket that recognizes metal-free citrate
cytidyldadenylate dinucleoside
-
activates GDP polymerization
diphosphate
-
activation of PNPase RNA synthesis activity at very low concentrations of phosphate
dithiothreitol
-
similar activation as with 2-mercaptoethanol
interferon-beta
-
close association between interferon-beta induced upregulation of enzyme and c-myc downregulation
-
KCl
-
maximal activation at 300 mM
KCl
-
salt is absolutely required for activity, maximal activity between 250 mM, inhibition above 1M
KCl
-
400 mM, 5fold activation of ADP polymerization
NaCl
-
salt is absolutely required for activity, maximal activity at 250 mM, inhibition above 1 M
NaCl
-
400 mM, 4fold activation of ADP polymerization
NH4+
-
maximal activation at 100 mM
NH4+
-
400 mM, 3 and 7fold activation of ADP polymerization and poly(A) phosphorolysis, respectively
phosphate
-
1-10 mM, strong activation of PNPase exonuclease activity
phosphate
-
maximal activation of recombinant PNPase RNA-derading activity at 20 mM
phosphate
-
degradation activity of chloroplast PNPase is dramatically enhanced, polymerization activity in the absence of phosphate
poly-L-lysine
-
stimulation of poly(A) synthesis, phosphorolysis of poly(A) is inhibited
poly-L-lysine
-
0.25 mg/ml, 78fold activation in the presence of 10 mM NaCl, 5fold activation in the presence of 250 mM NaCl
Polyarginine
-
stimulation of poly(A) synthesis, phosphorolysis of poly(A) is inhibited
Polyornithine
-
stimulation of poly(A) synthesis, phosphorolysis of poly(A) is inhibited
putrescine
-
optimal polymerization activity requires polyamines, 2fold increase in activity at 30 mM
spermidine
-
0.1-1.0 mM, activates ADP-phosphate exchange 2fold
spermidine
-
optimal polymerization activity requires polyamines, 1.4fold increase in activity at 30 mM
spermine
-
0.1-1.0 mM, activates ADP-phosphate exchange 2fold
spermine
-
optimal polymerization activity requires polyamines, 2fold increase in activity at 30 mM
mercaptoethanol
-
20 mM, 3fold activation
additional information
O87792, -
the enzyme expression is induced upon cold shock, transcriptional regulation, overview
-
KM VALUE [mM]
KM VALUE [mM] Maximum
SUBSTRATE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
0.42
-
ADP
-
pH 8.4
1
-
ADP
-
pH 8.0, 20C, ADP-phosphate exchange reaction
1
-
ADP
-
approx. value, also for CDP and UDP polymerization; pH 9.5, 37C, approx. value
1
-
CDP
-
pH 9.5, 37C, approx. value
0.000166
-
globin mRNA
-
pH 8.0, 37C, phosphorolysis of poly(A)tail from rabbit globin mRNA
-
0.05
-
heptauridylate
-
phosphorolysis reaction
0.033
-
nonaadenylate
-
phosphorolysis reaction
-
0.25
-
phosphate
-
pH 8.0, 20C, ADP-phosphate-exchange reaction
0.32
-
Poly(A)
-
pH 8.0, 37C
0.25
-
tetrauridylate
-
phosphorolysis reaction
-
2.5
-
triadenylate
-
phosphorolysis reaction
0.4
-
UDP
-
pH 8.0, 30C
1
-
UDP
-
pH 9.5, 37C, approx. value
0.05
-
Mg2+
-
-
additional information
-
additional information
-
values for Km with polynucleotides longer than 20 nucleotides are much smaller than the Km for oligonucleotides which lies at approx. 0.05 mM
-
additional information
-
additional information
-
enzyme binding with RNA displays an apparent sigmoid curve, with a Kd of 16 nM
-
TURNOVER NUMBER [1/s]
TURNOVER NUMBER MAXIMUM[1/s]
SUBSTRATE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
3.33
-
adenylic acid
-
synthesis of a copolymer of adenylic acid
3.33
-
cytidylic acid
-
synthesis of a copolymer of cytidylic acid
3.33
-
guanylic acid
-
synthesis of a copolymer of guanylic acid
75
-
Polyadenylic acid
-
-
3.33
-
uridylic acid
-
synthesis of a copolymer of uridylic acid
Ki VALUE [mM]
Ki VALUE [mM] Maximum
INHIBITOR
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
0.003
0.004
dADP
-
pH 9.0, 37C, inhibition of ADP polymerization
SPECIFIC ACTIVITY [µmol/min/mg]
SPECIFIC ACTIVITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
0.0002
-
-
incorporation of UDP into polynucleotide
0.02
-
-
ADP polymerization in crude extract
2
-
-
at pH 10.5
3.8
-
-
ADP polymerization
27.67
-
-
-
34.08
-
-
incorporation of GDP
additional information
-
-
0.0006 mmol/absorbance at 280 nm/min, ADP-P exchange activity
additional information
-
-
recombinant enzyme activity is measured as repression of beta-galactosidase activity in the reporter expression sytem, RNA binding affinity and in vitro RNA-binding activities of wild-type and mutant enzymes, overview
pH OPTIMUM
pH MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
5
-
-
polymerization of ADP
7
9
-
polymerization of GDP
7
-
-
assay at
7.2
-
-
phosphorolysis
7.4
-
-
assay at
7.5
-
-
assay at
7.5
-
-
assay at, reverse polymerization reaction
7.5
-
-
assay at
7.8
-
-
ADP-phosphate exchange reaction
8
9
-
phosphorolysis
8
-
-
phosphorolysis
8
-
-
assay at, forward degradation reaction
8
-
G8TCS8
assay at
8.2
-
-
phosphorolysis of poly(A)
8.5
-
-
polymerization of ADP
9.5
-
-
or above, polymerization
9.7
-
-
poymerization of ADP, CDP or UDP
10
-
-
or above, polymerization
10
-
-
polymerization of ADP
10.5
-
-
polymerization of GDP
10.5
-
-
-
pH RANGE
pH RANGE MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
5
9.5
-
almost no activity below
7.2
9
-
phosphorolysis of poly(A), approx. 25% of maximal activity at pH 7.3 and pH 9.1, respectively
7.5
9.3
-
approx. 60% of maximal activity at pH 7.5, approx. 70% of maximal activity at pH 9.3
7.6
8.8
-
approx. 40% of maximal activity at pH 7.6, approx. 70% of maximal activity at pH 8.8
8.4
10
-
polymerization of ADP, approx. 25% of maximal activity at pH 8.6
9.5
11.5
-
14% of maximal activity at pH 9.5, 70% of maximal activity at pH 11.5
TEMPERATURE OPTIMUM
TEMPERATURE OPTIMUM MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
25
-
-
assay at
30
-
-
60 min assay
35
-
-
10 min assay
36
-
-
synthesis of poly U
37
-
-
assay at
37
-
-
assay at
37
-
-
assay at
37
-
-
assay at
37
-
-
assay
37
-
-
assay at
37
-
G8TCS8
assay at
37
-
-
assay at
40
-
-
shows the highest activity below 40C
45
55
-
polymerization of UDP and CDP
55
-
-
polymerization of UDP with (Ap)3A as primer
60
-
-
polymerization of ADP and GDP, phosphorolysis of poly A
70
-
-
poymerization of ADP, CDP or GDP with (Ap)3A as primer
pI VALUE
pI VALUE MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
4.2
-
-
isoelectric focusing
4.9
-
-
isoelectric focusing
6.1
-
-
isoelectric focusing
6.1
-
-
isoelectric focusing, minor band at pH 6.8
SOURCE TISSUE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
SOURCE
-
free-living and symbiotic
Manually annotated by BRENDA team
Sinorhizobium meliloti F-28
-
free-living and symbiotic
-
Manually annotated by BRENDA team
Arabidopsis thaliana Col-0.
-
-
-
Manually annotated by BRENDA team
additional information
-
intracellular levels of PNPase are regulated by polyadenylation levels of transcripts
Manually annotated by BRENDA team
additional information
-
enzyme expression level analysis, overview
Manually annotated by BRENDA team
LOCALIZATION
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
GeneOntology No.
LITERATURE
SOURCE
Arabidopsis thaliana Col-0.
-
-
-
Manually annotated by BRENDA team
G8TCS8
structure of the S1 pore in exosomes and the KH pore in hPNPase, overview
-
Manually annotated by BRENDA team
-
membrane vesicles
Manually annotated by BRENDA team
-
localizes to the intermembrane space of mitochondria as a peripheral membrane protein in a multimeric complex
Manually annotated by BRENDA team
-
basal and interferon-beta induced enzyme is efficiently imported into mitochondria with coupled processing of the N-terminal targeting sequence. It localizes to the intermembrane space as a peripheral membrane protein in a multimeric complex
Manually annotated by BRENDA team
-
located to intermembrane space
Manually annotated by BRENDA team
-
mammalian PNPase contains an N-terminal mitochondrial localization signal facilitating its subcellular localization in mitochondria
Manually annotated by BRENDA team
additional information
G8TCS8
KH pore in PNPase versus S1 pore in exosomes
-
Manually annotated by BRENDA team
PDB
SCOP
CATH
ORGANISM
Caulobacter crescentus (strain ATCC 19089 / CB15)
Caulobacter crescentus (strain ATCC 19089 / CB15)
Caulobacter crescentus (strain ATCC 19089 / CB15)
Escherichia coli (strain K12)
Escherichia coli (strain K12)
Escherichia coli (strain K12)
Escherichia coli (strain K12)
Escherichia coli O139:H28 (strain E24377A / ETEC)
Escherichia coli O139:H28 (strain E24377A / ETEC)
Escherichia coli O139:H28 (strain E24377A / ETEC)
Streptococcus mutans serotype c (strain ATCC 700610 / UA159)
MOLECULAR WEIGHT
MOLECULAR WEIGHT MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
75000
-
-
gel filtration
100000
-
-
low molecular weight form catalyzing phosphorolysis but unable to catalyze the polymerization of NDP's, can only phosphorolyze short-chain polymers and requires higher Mg2+ ion concentration
150000
-
-
glycerol density gradient centrifugation
150000
-
-
sedimentation analysis
160000
-
-
gel filtration
190000
-
-
native PAGE, gel filtration
200000
-
-
this form requires Mn2+ for NDP polymerization and has a higher Km for poly(A) phosphorolysis
207600
-
-
equilibrium sedimentation analytical ultracentrifugation
210000
-
-
low speed sedimentation equilibrium
215000
240000
-
gel filtration
220000
-
-
native PAGE
230000
-
-
ultracentrifugation, equilibrium sedimentaion analysis
230000
-
-
enzyme form T, sedimentation equilibrium ultracentrifugation
230000
-
-
gel filtration
237000
-
-
sedimentation equilibrium
240000
-
-
sedimentation equilibrium
240000
-
G8TCS8
recombinant enzyme, gel filtration
252000
-
-
enzyme form A
270000
-
-
enzyme form I, sedimentation equilibrium ultracentrifugation
275000
-
-
native PAGE
275000
-
-
native PAGE
365000
-
-
enzyme form B
580000
600000
-
native and recombinant PNPase form a homo-multimer complex, gel filtration
additional information
-
-
PNPase, the endoribonuclease RNase E, a DEAD-RNA helicase and the glycolytic enzyme enolase are associated with a high molecular weight complex, the degradosome
SUBUNITS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
?
-
alpha3,beta2 or alpha3,betan, x * 86000 + x * 48000, enzyme form B is obtained by keeping the ionic strength at 200 mM during purification on Sephadex G-200, at lower salt concentrations the beta subunit tends to dissociate and the enzyme reverts to the A form
?
-
x * 71000, enzyme form T, enzyme form I shows several bands of different molecular sizes, SDS-PAGE
?
Q53597
x * 81132, electrospray mass spectrometry; x * 81133, deduced from nucleotide sequence
dimer
-
2 * 76000, SDS-PAGE
dimer
-
2 * 100000, SDS-PAGE in the presence of 2-mercaptoethanol
homotrimer
-
-
homotrimer
Escherichia coli MG1655
-
-
-
tetramer
-
4 * 51000
tetramer
-
alpha4, 4 * 70000, SDS-PAGE
trimer
-
alpha3, 3 * 84000-95000, enzyme form A, ultrastructural observations
trimer
-
alpha3, 3 * 84000-95000, enzyme form A, ultrastructural observations; SDS-PAGE
trimer
-
1 * 92000 + 1 * 73000 + 1 * 35000, SDS-PAGE
trimer
-
3 * 72000, SDS-PAGE in presence of 2-mercaptoethanol
trimer
-
3 * 50000, denaturing PAGE
trimer
-
3 * 92000, SDS-PAGE, prior to purification the enzyme exists in oligomeric forms
trimer
-
alpha3, 3 * 91000, SDS-PAGE
trimer
-
3 * 86000, SDS-PAGE
trimer
A7ZS61
x-ray crystallography
trimer
-
3 * 90000, SDS-PAGe and homology modeling
trimer
-
-
trimer
G8TCS8
3 * 80900, about, sequence calculation, the trimeric hPNPase has a hexameric ring-like structure formed by six RNase PH domains, capped with a trimeric KH pore, the enzyme has a conserved GXXG motif in the KH domain, structural model of hPNPase, overview
trimer
-
the enzyme has a ring-like, trimeric architecture that creates a central channel where phosphorolytic active sites reside. One face of the ring is decorated with RNA-binding K-homology (KH) and S1 domains, domain organization with modular organization of conserved structural domains, overview
trimer
Caulobacter vibrioides NA1000
-
the enzyme has a ring-like, trimeric architecture that creates a central channel where phosphorolytic active sites reside. One face of the ring is decorated with RNA-binding K-homology (KH) and S1 domains, domain organization with modular organization of conserved structural domains, overview
-
trimer
-
alpha3, 3 * 91000, SDS-PAGE
-
trimer
Thermus thermophilus HB-8
-
1 * 92000 + 1 * 73000 + 1 * 35000, SDS-PAGE
-
monomer
-
domain organization of the enzyme monomer, homology modeling with KH domain and S1 domain, overview
additional information
-
enzyme domains within residues 158-262 and 473-577 contain interaction sites for RNase E within a betabetaalphabetabetaalpha domain configuration
additional information
-
enzyme interacts with AKT kinase coactivator TCL1. The AKT interaction domain on TCL1 binds either Rnase PH repeat domain on PNPase without influencing its RNA degrading activity; polyribonucleotide phosphorylase interacts with AKT kinase coactivator TCL1. The AKT interaction domain on TCL1 binds either polyribonucleotide phosphorylase PH repeat domain without influencing its RNA degrading activity, compatible with predicted docking models for a TCL1-PNPase complex
additional information
G8TCS8
domain organization of full-length and S1 domain-truncated hPNPase. overview
additional information
-
two conserved catalytic RNase PH regions, are present at the N-terminus of the enzyme
POSTTRANSLATIONAL MODIFICATION
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
proteolytic modification
-
processing of the N-terminal targeting sequence upon import into mitochondria
Crystallization/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
purified recombinant RNA-free and RNA-bound PNPase, as protein-peptide and protein-RNA complexes, mixing of PNPase recognition peptide from RNase E, KPRRGWWRR, with apo-PNPase in a 2:1 ratio, sitting drop vapour diffusion method, mixing of equal volumes of protein solution and cyrstallization solution, containing w/v PEG 3350, 0.1 M Bis-Tris, pH 5.5, 0.1 M ammonium acetate for RNA-bound crystals, and with the apo-enzyme containing w/v PEG3000, 0.1 M trisodium citrate, pH 5.5, for hexagonal crystals and w/v PEG 3350, 0.15 M DL-malic acid for rhombohedral crystals, 18C, 1 week, X-ray diffraction structure determination aand analysis at 2.6-3.3 A resolution, molecular replacement
-
PNPase complexed with the recognition site from RNase E and with manganese in the presence or in the absence of modified RNA, hanging droplet vapor diffusion method, crystals for the PNPase core/RNase E micro-domain crystals are grown using 0.2 M ammonium nitrate, and 20% (w/v) PEG 3350, crystals for the PNPase core/RNase E microdomain-RNA complex are produced using 0.2 M diammonium hydrogen citrate, and 17% PEG 3350. The optimal reservoir buffer for the PNPase core/RNase E micro-domain-RNA-tungstate crystals is composed of 0.2 M di-ammonium hydrogen citrate, 17% PEG 3350, about pH 4.5, 50 mM disodium tungstate. Crystals for the PNPase core/RNase E micro-domain-Mn2+ co-crystals are prepared using 2.5 M NaCl, 9% (w/v) PEG 6000, 20 mM sodium citrate, and 20 mM manganese acetate tetrahydrate
A7ZS61
three-dimensional modeling of enzyme based on Streptomyces antibioticus protein structure. The binding domain for RNase E is located on the monomer surface, facing outward from the trimeric tertiary structure
-
wild-type and C-terminal KH/S1 domain truncated mutant at resolutions of 2.6 and 2.8 A, respectively. The six PH domains assemble into a ring-like structure containing a central channel
-
homology modeling based on structure of Streptomyces antibioticus ortholog. Enzyme displays a doughnut-shaped trimer with a central channel to accommodate a single-stranded RNA molecule. The circular structure is composed of the first and second core domains, while the KH and S1 RNA binding domains are located at the top, adjacent to the gate entrance into the circle
-
wild-type and S1 domain-truncated hPNPase, hanging-drop vapor diffusion method, mixxing of 0.001 ml of 10 mg/ml protein in 50 mM Tris, pH 8.0, and 150 mM NaCl, with 0.001 ml of reservoir solution containing 0.1 M citrate, pH 5.0, 10% v/v 2-propanol and 26% v/v PEG 400, room temperature, X-ray diffraction structure determination and analysis at 2.1 A resolution, molecular replacement method
G8TCS8
protein solution mixed at 3/1 ratio with well solution consisting of 2 M ammonium sulfate, 100 mM Tris-HCl, pH 8.5, 5 mM dithiothreitol and 0.75 mM Na2AsO4, crystals are harvested in a so called mirror solution from equilibrated droplets with buffer replacing enzyme solution and no added Na2AsO4, crystals of native PNPase, a tungstate derivative and a seleno-methionyl derivative
Q53597
pH STABILITY
pH STABILITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
5
10
-
incubation at 4C for 2 d, no loss of activity, rapid inactivation below pH 5.0
TEMPERATURE STABILITY
TEMPERATURE STABILITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
40
-
-
PNPase is quite sensitive to heat treatment
55
60
-
10 min, no loss of activity
55
-
-
unstable above
65
-
-
activity gradually lost above
65
-
-
rapid and irreversible inactivation
70
-
-
10 min, 0.05 mg/ml enzyme, less than 10% loss of activity
GENERAL STABILITY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
highly susceptible to proteolysis
-
stable against several freezing and thawing cycles
-
enzyme form I is highly susceptible to proteolytic degradation
-
sensitive to proteolytic digestion
-
insensitive to freezing
-
sensitive to proteolytic digestion
-
stable against several freezing and thawing cycles
-
PNPase is quite sensitive to heat treatment and is endowed with remarkable halotolerance
-
stable against several freezing and thawing cycles
-
STORAGE STABILITY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
-60C, several months, no loss of activity
-
-20C, 3 mg/ml enzyme concentration, 3 years, no loss of activity
-
-20C, dilute solution, at least 2 months, no loss of activity
-
-75C, several months, no loss of activity
-
4C, 1 week, 50% loss of activity
-
-20C, partially purified enzyme frozen and thawed after overnight storage, 30-40% loss of activity
-
4C, 1 week, 44% loss of phosphorolytic activity and 53% loss of NDP-phosphate exchange activity
-
-20C, 100 mM NaCl, 0.1 mM EDTA, 0.1 mM dithiothreitol, 0.01 mM PMSF, 30% glycerol, 50 mM Tris-HCl, pH 8, at least 8 months, no loss of activity
-
4C, at least 6 months, no loss of activity
-
-20C, dilute solution, at least 2 months, no loss of activity
-
Purification/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
ammonium sulfate, ethanol, calcium phosphate gel, protamine, hydroxylapatite
-
phase partition, ammonium sulfate, agarose gel filtration, DEAE-Sephadex
-
Streptomycin sulfate, ammonium sulfate, Zncl2 precipitation, DEAE-cellulose
-
recombinant N-terminally GST-tagged enzyme fragments from Escherichia coli by glutathione affinity chromatography, of His6-tagged enzyme fragments by nickel affinity chromatography, followed by gel filtration in both procedures
-
ammonium sulfate, polyethlene glycol 6000, DEAE-Sepharose, QAE-Sephadex, blue-Sepharose, glycerol gradient centrifugation
-
affinity chromatography
-
ammonium sulfate precipitation, Q-Sepharose column chromatography, and Mono-Q column chromatography
A7ZS61
ammonium sulfate, DEAE-cellulose, RNA-sepharose
-
recombinant wild-type and mutant enzymes from Escherichia coli strain ENS134-3
-
polyethylene imine, Sepharose 4B, affinity chromatography on oligo(dT)-Sepharose
-
MonoQ colmn chromatography, metal ion affinity chromatography, and Superdex 200 gel filtration
-
recombinant N-terminally His-tagged wild-type and mutant enzymes from Escherichia coli strain BL21-CodonPlus (DE3)-RIPL by nickel affinty chromatography and gel filtration
G8TCS8
phosphocellulose chromatography, enzyme forms I and T
-
DEAE-Sephadex, enzyme from healthy and TMV-infected leaves
-
DEAE-cellulose, Sephacryl S-300, Mono Q, poly(A)-Sepharose
-
manganese-RNA gel, DEAE-cellulose, ammonium sulfate, partially purified
-
DEAE-cellulose, ammonium sulfate, Sephadex G-200
-
phosphocellulose, DEAE-Sephadex, Blue-Sepharose, Sephacryl s-300
-
heat, ammonium sulfate, Sephadex G-200, DEAE-cellulose
-
recombinant PNPase, nitrilotriacetic acid agarose, Mono Q
Q41370
recombinant enzyme, HiTrap Q, HiFlow Phenyl-Sepharose
Q53597
polymin P, DEAE-cellulose, Sephadex G-150, DEAE-cellulose, Sephadex G-200
-
ammonium sulfate, DEAE-cellulose, gel filtration, poly(A)-Sepharose
-
ammonium sulfate, DEAE-cellulose, heparin-Sepharose, DEAE-Sephadex
-
ultracentrifugation, ammonium sulfate, QAE-Sephadex a-25, DEAE-cellulose, hydroxyapatite, purified enzyme loses poly(A) phosphorylating activity
-
Cloned/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
expressed in an Escherichia coli strain that lacks polynucleotide phosphorylase
-
overexpresssion of FLAG-tagged PNPase in Escherichia coli, ectopic expression in transgenic Arabidopsis plant
-
gene pnp, cloned in a plasmid with rne gene, encoding endoribonuclease RNase E, fragments, expression of N-terminally GST- or His6-tagged enzyme fragments in Escherichia coli
-
expressed in an Escherichia coli strain that lacks polynucleotide phosphorylase
-
expressed in Escherichia coli BL21(DE3) cells
A7ZS61
expression of enzyme mutant R153A/R372A/R405A/R409A in Escherichia coli strain BL21(DE3)
-
expression of wild-type and mutant enzymes in Escherichia coli strain ENS134-3 from modofied plasmid pAW101 and in beta-galactosidase reporter strain IBPC7322(lambdaGF2), overview
-
overexpression in Escherichia coli in the presence or absence of increased levels of polyadenylated transcripts
-
ectopic expression of human polynucleotide phosphorylase, i.e. hPNPaseold-35, in human HO-1 melanoma cells results in growth suppression
-
enhanced expression of hPNPase(old-35) via a replication-incompetent adenovirus (Ad.hPNPase(old-35)) in human melanoma cells and normal melanocytes
-
expressed in Escherichia coli Rosetta cells
-
expression in HeLa cell
-
expression of N-terminally His-tagged wild-type and mutant enzymes in Escherichia coli strain BL21-CodonPlus (DE3)-RIPL
G8TCS8
gene cloning using an overlapping pathway screening strategy designed to identify genes coordinately regulated during the processes of cellular differentiation and senescence, overview. Expression in HO-1 cells
-
gene pnp, DNA and amino acid sequence determination and analyis, genetic organization, determination of the transcription pattern of pnp upon cold shock and at 30C, overview
O87792, -
expression in Escherichia coli
-
expression of PNPase lacking the chloroplast transit peptide and several deletion proteins in Escherichia coli
Q41370
overexpression of gpsI gene encoding PNPase in Escherichia coli
Q53597
expression in Escherichia coli
Q9ZAE1
EXPRESSION
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
PNPase expression is repressed by the response regulator phosphorus starvation response1 under phosphorus limitation
-
PNPase activity is lower in virulent strains of Dichelobacter nodosus
A5EXU0, -
ENGINEERING
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
D625N
-
naturally occuring mutation in the catalytic site, inactive mutant
G596R
-
naturally occuring mutation near the catalytic domain, inactive mutant. Mutant G596R fails to fold correctly, perhaps as a consequence of its inability to bind phosphate, and is thus marked for degradation
D625N
Arabidopsis thaliana Col-0.
-
naturally occuring mutation in the catalytic site, inactive mutant
-
A552T
-
complementation of growth defect at 15C of host strain. Modest effect of mutation on phosphorolytic activity and protein abundance; ratio of phosphorolytic activity to polynucleotide phosphorylase activity 0.7, as compared with 1.0 in wild-type
C1310T
-
mutation invovled in sRNA regulation defects
C277T
-
mutation invovled in sRNA regulation defects
C943T
-
mutation invovled in sRNA regulation defects
DELTA549-709
-
complementation of growth defect at 15C of host strain
E371K
-
complementation of growth defect at 15C of host strain. Modest effect of mutation on phosphorolytic activity and protein abundance; ratio of phosphorolytic activity to polynucleotide phosphorylase activity 0.6, as compared with 1.0 in wild-type
E81D
-
complementation of growth defect at 15C of host strain. Increase in PNPase abundance without significantly impairing phosphorolytic activity; impaired growth at 15C, ratio of phosphorolytic activity to polynucleotide phosphorylase activity 1.6, as compared with 1.0 in wild-type
E81K
-
complementation of growth defect at 15C of host strain. Increase in PNPase abundance without significantly impairing phosphorolytic activity; impaired growth at 15C, ratio of phosphorolytic activity to polynucleotide phosphorylase activity 0.4, as compared with 1.0 in wild-type
F635A
-
site-directed mutagenesis, the mutant enzyme shows reduced activity compared to the wild-type enzyme
F635A/F638A/H650A
-
site-directed mutagenesis, the mutant enzyme shows highly reduced activity and an increased RNA binding constant compared to the wild-type enzyme
F635R/F638R/H650R
-
site-directed mutagenesis, the mutant enzyme shows reduced activity and an increased RNA binding constant compared to the wild-type enzyme
F638A
-
site-directed mutagenesis, the mutant enzyme shows reduced activity and an increased RNA binding constant compared to the wild-type enzyme
G1307A
-
mutation invovled in sRNA regulation defects
G1466A
-
mutation invovled in sRNA regulation defects
G570C
-
site-directed mutagenesis, the mutant enzyme shows highly reduced activity and an increased RNA binding constant compared to the wild-type enzyme
G570C/V679A
-
site-directed mutagenesis, the mutant enzyme shows reduced activity compared to the wild-type enzyme
H650A
-
site-directed mutagenesis, the mutant enzyme shows reduced activity compared to the wild-type enzyme
I555T
-
site-directed mutagenesis, the mutant enzyme shows slightly reduced activity compared to the wild-type enzyme
I576A
-
site-directed mutagenesis, the mutant enzyme shows reduced activity and an increased RNA binding constant compared to the wild-type enzyme
I576A/F638A
-
site-directed mutagenesis, the mutant enzyme shows reduced activity compared to the wild-type enzyme
I576T
-
site-directed mutagenesis, the mutant enzyme shows reduced activity and an increased RNA binding constant compared to the wild-type enzyme
I576T/F638A
-
site-directed mutagenesis, the mutant enzyme shows reduced activity and an increased RNA binding constant compared to the wild-type enzyme
I576T/T585A
-
site-directed mutagenesis, the mutant enzyme shows reduced activity compared to the wild-type enzyme
K571L
-
site-directed mutagenesis, the mutant enzyme shows reduced activity and an increased RNA binding constant compared to the wild-type enzyme
P98L
-
complementation of growth defect at 15C of host strain, forms of smaller colonies than host strain. Severe reduction of enzyme activity and increased PNPase expression levels; impaired growth at 15C, ratio of phosphorolytic activity to polynucleotide phosphorylase activity 0.03, as compared with 1.0 in wild-type
R100D
-
growth at 37C, not able to grow at 15C
R153A/R372A/R405A/R409A
-
site-directed mutagenesis
R319H
-
growth at 37C, not able to grow at 15C
R398D/R399D
-
growth at 37C, not able to grow at 15C
R83A
A7ZS61
the mutation has little apparent effect on activity but causes the full-length PNPase to stall on RNA oligomers shorter than eight nucleotides
R97C
-
complementation of growth defect at 15C of host strain. Severe reduction of enzyme activity and increased PNPase expression levels; ratio of phosphorolytic activity to polynucleotide phosphorylase activity 0.1, as compared with 1.0 in wild-type
V304A/V305D
-
complementation of growth defect at 15C of host strain; ratio of phosphorolytic activity to polynucleotide phosphorylase activity 0.02, as compared with 1.0 in wild-type
V521I
-
complementation of growth defect at 15C of host strain. Modest effect of mutation on phosphorolytic activity and protein abundance; ratio of phosphorolytic activity to polynucleotide phosphorylase activity 0.5, as compared with 1.0 in wild-type
V639D
-
complementation of growth defect at 15C of host strain, migrates slower than wild-type on SDS-PAGE, forms of smaller colonies than host strain. Increase in PNPase abundance without significantly impairing phosphorolytic activity; impaired growth at 15C, ratio of phosphorolytic activity to polynucleotide phosphorylase activity 0.6, as compared with 1.0 in wild-type
W233Stop
-
complementation of growth defect at 15C of host strain
R100D
Escherichia coli JM83
-
growth at 37C, not able to grow at 15C
-
R319H
Escherichia coli JM83
-
growth at 37C, not able to grow at 15C
-
R398D/R399D
Escherichia coli JM83
-
growth at 37C, not able to grow at 15C
-
C1310T
Escherichia coli MG1193
-
mutation invovled in sRNA regulation defects
-
C277T
Escherichia coli MG1193
-
mutation invovled in sRNA regulation defects
-
C943T
Escherichia coli MG1193
-
mutation invovled in sRNA regulation defects
-
D135G
-
unlike trimeric wild-type, mutant is monomeric. Almost complete inhibition of degradation and polyadenylation activities
D544G
-
decrease in degradation activity, increase in polymerization
G596R
Arabidopsis thaliana Col-0.
-
naturally occuring mutation near the catalytic domain, inactive mutant. Mutant G596R fails to fold correctly, perhaps as a consequence of its inability to bind phosphate, and is thus marked for degradation
-
additional information
-
construction of a pnp inactivation mutant, comparative proteomic analysis and 81-176 phenotype, overview. Levels of peb3 and katA mRNA are significantly decreased in the pnp mutant strain compared to the parental strain, while gene expression of luxS and hsp90 remains unaffected by the pnp mutation, but not protein expression, overview. Poly(A) degradation by lysates of the pnp mutant strain is almost totally non-responsive to phosphate addition
K571Q
-
site-directed mutagenesis, the mutant enzyme shows reduced activity and an increased RNA binding constant compared to the wild-type enzyme
additional information
-
deletion of KHS1 domain, ratio of phosphorolytic activity to polynucleotide phosphorylase activity 0.6, as compared with 1.0 in wild-type. Deletion mutant lacking amino acids 549-709, no growth at 15C. Both first and second core domains are involved in the catalysis of the phosphorolytic reaction, and both phosphorolytic activity and RNA binding are required for autogenous regulation and growth in the cold
additional information
-
construction of hybrid proteins by replacing the S1 RNA binding domain of RNase II for the S1 from enzyme. PNPase S1 domain can partially restore the RNA-binding ability and exonucleolytic activity of Rnase II and is able to induce the trimerization of the Rnase II-PNPase hybrid protein
additional information
-
C-terminal KH/S1 domain truncated mutant, crystallization data. Mutant binds and cleaves RNA less efficiently with an 8fold reduced binding affinity and forms a less stable trimer. Mutation of Arg-residues in the central channel neck region produces defective enzymes that either bind and cleave RNA less efficiently or generate longer cleaved oligonucleotide products
additional information
-
study on the effect of specific mutations in the two RNA binding domains KH and S1. Removal of critical motifs that stabilize the hydrophobic core of each domain, as well as a complete deletion of both severely impaireds binding to RNA. all mutants are enzymatically active but display significant changes in the kinetic behaviour of both phosphorolysis and polymerization activities. Mutants do not autoregulate efficiently and are unable to complement the growth defect of a chromosomal enzmye deletion at 18C
additional information
P05055
several new pnp alleles constructed. To identify specific cis-acting determinants of PNPase autoregulation and discriminate between the two proposed models, several pnpL DELTApnp-871 mutants and one DELTApnp-1010t DELTApnp-871 chromosomal double mutant are constructed
additional information
-
in a mutant lacking polyribonucleotide phosphorylase activity, the pattern of outer membrane proteins is changed. In stationary phase, stationary phase regulator MicA RNA levels are increased in the mutant, leading to a decrease in the levels of its target ompA mRNA and the respective protein
additional information
-
deletion of gene pnp in Eschericchia coli strain C-1a leading to strong cell aggregation in liquid medium dependent on the extracellular polysaccharide poly-N-acetylglucosamine. Operon pgaABCD transcript levels are increased in the pnp mutant compared to the wild-type enzyme. Inactivation of the pnp gene induces poly-N-acetylglucosamine production. The aggregative phenotype of the C-5691 (DELTApnp) strain is complemented by basal expression from a multicopy plasmid of the pnp gene under araBp promoter, overview
additional information
-
construction of domain deletion mutants DELTAKH DELTAS1, DELTAKH, and DELTAS1
additional information
-
construction of a strain in which PNPase activity is uncoupled from the degradosome through the deletion of the C-terminal degradosome-scaffold-ing domain of RNase E. Compared with the parental strain, significant differences are distributed across many metabolic pathways, including the Krebs cycle, amino acid synthesis, and glycolysis in the mutant strain. Salient differences are seen for amino acids and increases in the concentrations of succinate, fumarate, and malate, suggesting uncoupling of the two halves of the Krebs cycle
additional information
-
genetic selection and screen for mutants defective in the post-transcriptional regulation of gene expression by sRNAs, i.e. CyaR, SgrS, and RyhB. Each of the pnp mutations isolated, as well as a pnp deletion, are transduced into strain DJ624, overview. The defect in sRNA regulation caused by the pnp mutations is independent of Hfq. While Hfq does not appear to be limiting, it seems possible that lack of PNPase leads to inactivation of Hfq
G1307A
Escherichia coli MG1193
-
mutation invovled in sRNA regulation defects
-
additional information
Escherichia coli MG1193
-
genetic selection and screen for mutants defective in the post-transcriptional regulation of gene expression by sRNAs, i.e. CyaR, SgrS, and RyhB. Each of the pnp mutations isolated, as well as a pnp deletion, are transduced into strain DJ624, overview. The defect in sRNA regulation caused by the pnp mutations is independent of Hfq. While Hfq does not appear to be limiting, it seems possible that lack of PNPase leads to inactivation of Hfq
-
additional information
Escherichia coli MG1655
-
construction of a strain in which PNPase activity is uncoupled from the degradosome through the deletion of the C-terminal degradosome-scaffold-ing domain of RNase E. Compared with the parental strain, significant differences are distributed across many metabolic pathways, including the Krebs cycle, amino acid synthesis, and glycolysis in the mutant strain. Salient differences are seen for amino acids and increases in the concentrations of succinate, fumarate, and malate, suggesting uncoupling of the two halves of the Krebs cycle; deletion of gene pnp in Eschericchia coli strain C-1a leading to strong cell aggregation in liquid medium dependent on the extracellular polysaccharide poly-N-acetylglucosamine. Operon pgaABCD transcript levels are increased in the pnp mutant compared to the wild-type enzyme. Inactivation of the pnp gene induces poly-N-acetylglucosamine production. The aggregative phenotype of the C-5691 (DELTApnp) strain is complemented by basal expression from a multicopy plasmid of the pnp gene under araBp promoter, overview
-
R153A/R372A/R405A/R409A
Escherichia coli MG1655
-
site-directed mutagenesis
-
additional information
Escherichia coli MG1693
-
in a mutant lacking polyribonucleotide phosphorylase activity, the pattern of outer membrane proteins is changed. In stationary phase, stationary phase regulator MicA RNA levels are increased in the mutant, leading to a decrease in the levels of its target ompA mRNA and the respective protein
-
G622D
G8TCS8
site-directed mutagenesis
additional information
-
depletion of enzyme by RNAi approach or overexpression of c-myc protects melanoma cells from interferon-beta mediated grwoth inhibition. Targeted overexpression of enzyme as a therapeutic strategy for c-myc overexpressing and interferon-beta resisitant tumors
additional information
-
enzyme depletion using RNAi does not affect mitochondrial RNA levels but impairs mitochondrial electrochemical membrane potential, decreases respiratory chain activity and correlates with altered mitochondrial morphology. This results in F0F1-ATP synthase instability, impaired ATP generation, lactate accumulation, and AMP kinase phosphorylation with reduced cell proliferation
additional information
-
overexpression of polynucleotide phosphorylase in HeLa cells under oxidative stress conditions reduces RNA oxidation and increases cell viability against H2O2 insult. Knock-down of enzyme decreases viability and increases 8-oxoguanosine levels in cells exposed to H2O2
additional information
-
the promoter of Progression Elevated Gene-3 functions selectively in a diverse array of human cancer cells. An adenovirus constructed with the Progression Elevated Gene-3 promoter driving expression of polyribonucleotide phosphorylase containing a C-terminal hemaglutinin-tag induces robust transgene expression, growth suppression, apoptosis, and cell-cycle arrest in a broad panel of pancreatic cancer cells
additional information
-
upon expression in Escherichia coli, human enzyme does not form hetero-complexes with Escheichia coli enzyme
additional information
-
stable silencing by establishing HeLa cell lines expressing shRNA. Silencing significantly affects processing and polyadenylation of mitochondrial mRNAs with different effects on different genes. The stable poly(A) tails at the 3' ends of COX1 transcripts are abolished, while COX3 poly(A) tails remain unaffected and ND5 and ND3 poly(A) extensions increase in length. Despite the lack of polyadenylation at the 3' end, COX1 mRNA and protein accumulate to normal levels, as is the case for all 13 mitochondria-encoded proteins. ATP depletion also alters poly(A) tail length
additional information
G8TCS8
generation of a S1 domain-lacking mutant enzyme, domain organization of full-length and S1 domain-truncated hPNPase. overview. Full-length and DELTAS1 hPNPase cleave the poly(A)12 and poly(U)12 RNA with similar activities and DELTAS1 hPNPase cleaves ssRNA substrate almost as efficiently as full-length PNPase
additional information
-
targeted overexpression of hPNPase represents a strategy to selectively downregulate RNA expression and consequently intervene in a variety of pathophysiological conditions, enzyme silencing in PNPase RNA interference-transfected HEK293 cells
additional information
-
human melanoma cells are infected with empty adenovirus or with an adenovirus expressing hPNPaseold-35 and identification of miRNAs differentially and specifically regulated by hPNPaseold-35
additional information
O87792, -
construction of gene pnp deletion mutants, the mutants do not exhibit cold sensitivity, phenotype, overview
additional information
-
enzyme inactivation strain, PNPase deficiency results in increased expression of salmonella plasmid virulence genes. Six genes are significantly upregulated, including spvABC, rtcB, entC, and STM2236. A growth advantage of the mutant strain in BALB/c mice depends on plasmid virulence gene spvR as well
additional information
-
enzyme deletion strain is less virulent in mouse than the isogenic wild-type. Enzyme deletion strains show enhanced levels of type III secretion system T3SS encoding transcripts and proteins. T3SS expression levels do not differ between enzyme deletion strains expressing active and inactive S1 RNA binding domain of enzyme which is required for normal T3SS activity; polynucleotide phosphorylase deletion strain is less virulent in mouse compared with the isogenic wild-type strain. Deletion strains possess enhanced levels of type III secretion system-encoding transcripts and proteins. A S1 variant of polynucleotide phosphorylase containing a disruption in its RNA-binding subdomain cannot restore normal type III secretion system activity
Renatured/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
after heating at 100C for 1 min 25-30% of the original activity can be recovered by dissolving the precipitate in 6 M guanidine-HCl followed by dialysis
-
refolding of SDS-PAGE purified PNPase diluted 50fold into enzyme buffer containing 0.5% Triton X-100 and 0.5 mg/ml bovine serum albumin
-
APPLICATION
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
medicine
-
depletion of enzyme by RNAi approach or overexpression of c-myc protects melanoma cells from interferon-beta mediated grwoth inhibition. Targeted overexpression of enzyme as a therapeutic strategy for c-myc overexpressing and interferon-beta resistant tumors
medicine
-
the apoptosis-inducing activity of polynucleotide phosphorylase is mediated by activation of double-stranded RNA-dependent protein kinase. Activation of RNA-dependent protein kinase by polynucleotide phosphorylase precedes phosphorylation of eukaryotic initiation factor-2A and induction of growth arrest and DNA damage-inducible gene 153, GADD153, that culminates in the shutdown of protein synthesis and apoptosis. Activation of RNA-dependent protein kinase by polynucleotide phosphorylase also instigates down-regulation of the antiapoptotic protein Bcl-xL. A dominant-negative inhibitor of RNA-dependent protein kinase, as well as GADD153 antisense or bcl-xL overexpression, effectively inhibits apoptosis induction by polynucleotide phosphorylase
medicine
-
the promoter of Progression Elevated Gene-3 functions selectively in a diverse array of human cancer cells. An adenovirus constructed with the Progression Elevated Gene-3 promoter driving expression of polyribonucleotide phosphorylase containing a C-terminal hemaglutinin-tag induces robust transgene expression, growth suppression, apoptosis, and cell-cycle arrest in a broad panel of pancreatic cancer cells, with minimal effects in normal immortalized pancreatic cells. Expression correlates with arrest in the G2/M phase of the cell cycle and up-regulation of the cyclin-dependent kinase inhibitors p21CIP1/WAF-1/MDA-6 and p27KIP1. In a nude mouse xenograft model,construct injections effectively inhibit growth of human pancreatic cancer cells in vivo
medicine
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targeted overexpression of hPNPaseold-35 might provide an effective therapeutic strategy for miR-221-overexpressing and IFN-resistant tumors, such as melanoma
molecular biology
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targeted overexpression of hPNPase represents a strategy to selectively downregulate RNA expression and consequently intervene in a variety of pathophysiological conditions
synthesis
Q9ZAE1
at the optimal temperature, polynucleotide phosphorylase completely destroys RNAs that possess even a very stable intramolecular secondary structure, but leaves intact RNAs whose 3' end is protected by chemical modification or by hybridization with a complementary oligonucleotide. This allows individual RNAs to be isolated from heterogeneous populations by degrading unprotected species. If oligonucleotide is hybridized to an internal RNA segment, the Tth polynucelotide phosphorylase stalls eight nucleotides downstream of that segment. This allows any arbitrary 5'-terminal fragment of RNA to be prepared with a precision similar to that of run-off transcription, but without the need for a restriction site