Literature summary for 2.7.7.8 extracted from

Nurmohamed, S.; Vaidialingam, B.; Callaghan, A.J.; Luisi, B.F.
Crystal structure of Escherichia coli polynucleotide phosphorylase core bound to RNase E, RNA and manganese: Implications for catalytic mechanism and RNA degradosome assembly (2009), J. Mol. Biol., 389, 17-33.

Cloned(Commentary)

Cloned (Comment)	Organism
expressed in Escherichia coli BL21(DE3) cells	Escherichia coli

Crystallization (Commentary)

Crystallization (Comment)	Organism
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	Escherichia coli

Crystallization (Comment)

Organism

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

Escherichia coli

Protein Variants

Protein Variants	Comment	Organism
R83A	the mutation has little apparent effect on activity but causes the full-length PNPase to stall on RNA oligomers shorter than eight nucleotides	Escherichia coli

Metals/Ions

Metals/Ions	Comment	Organism	Structure
Mg2+	essential cofactor for PNPase catalysis	Escherichia coli
Mn2+	Mn2+ can substitute for Mg2+ as an essential co-factor for PNPase catalysis	Escherichia coli

Organism

Organism	UniProt	Comment	Textmining
Escherichia coli	A7ZS61	-	-

Purification (Commentary)

Purification (Comment)	Organism
ammonium sulfate precipitation, Q-Sepharose column chromatography, and Mono-Q column chromatography	Escherichia coli

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
additional information	under conditions of excess nucleoside diphosphate and low concentrations of phosphate, PNPase catalyses the reverse reaction to add 3' extensions to transcripts	Escherichia coli	?	-	?
RNAn + a nucleoside diphosphate	-	Escherichia coli	RNAn+1 + phosphate	-	?

Subunits

Subunits	Comment	Organism
trimer	x-ray crystallography	Escherichia coli

Synonyms

Synonyms	Comment	Organism
PNPase	-	Escherichia coli
polynucleotide phosphorylase	-	Escherichia coli

General Information

General Information	Comment	Organism
physiological function	PNPase is a processive exoribonuclease that contributes to messenger RNA turnover and quality control of ribosomal RNA precursors	Escherichia coli