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Information on EC 2.4.99.18 - dolichyl-diphosphooligosaccharide-protein glycotransferase
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2.4.99.18 dolichyl-diphosphooligosaccharide-protein glycotransferaseIUBMB Comments
Occurs in eukaryotes that form a glycoprotein by the transfer of a glucosyl-mannosyl-glucosamine polysaccharide to the side-chain of an L-asparagine residue in the sequence -Asn-Xaa-Ser- or -Asn-Xaa-Thr- (Xaa not Pro) in nascent polypeptide chains. The basic oligosaccharide is the tetradecasaccharide Glc3Man9GlcNAc2 (for diagram {polysacc/Dol14}). However, smaller oligosaccharides derived from it and oligosaccharides with additional monosaccharide units attached may be involved. See ref for a review of N-glycoproteins in eukaryotes. Man3GlcNAc2 seems to be common for all of the oligosaccharides involved with the terminal N-acetylglucosamine linked to the protein L-asparagine. Occurs on the cytosolic face of the endoplasmic reticulum. The dolichol involved normally has 14-21 isoprenoid units with two trans double-bonds at the omega end, and the rest of the double-bonds in cis form.
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Word Map
- 2.4.99.18
-
n-glycosylation
-
n-linked
- glycans
-
lipid-linked
-
sequons
-
asparagine-linked
- jejuni
- campylobacter
- dolichol
-
ribophorins
- otase
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cotranslational
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bloc
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dolichol-linked
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translocon
- glc3man9glcnac2
- heptasaccharide
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s-layer
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underglycosylation
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preassembled
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mannosyltransferases
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glycoengineering
-
hypoglycosylation
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hetero-oligomeric
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single-subunit
-
translocon-associated
- man9glcnac2
- lari
- drug development
- biotechnology
- medicine
- n-glycoproteins
-
glycoproteomics
- pilins
The expected taxonomic range for this enzyme is: Eukaryota, Archaea, Bacteria
Reaction Schemes
Synonyms
oligosaccharyltransferase, oligosaccharyl transferase, oligosaccharyltransferase complex, ost3p, wbp1p, ost6p, oligosaccharide transferase, swp1p, tbstt3a, tbstt3b, 
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
AglB
AlgB
asparagine N-glycosyltransferase
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-
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dolichyl-diphosphooligosaccharide--protein glycosyltransferase subunit OST2
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dolichyldiphosphooligosaccharide-protein oligosaccharyltransferase
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EC 2.4.1.119
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-
formerly
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glycosyltransferase, dolichyldiphosphooligosaccharide-protein
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-
-
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glycosyltransferase, dolichylpyrophosphodiacetylchitobiose-protein
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-
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oligomannosyltransferase
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-
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oligosaccharide transferase
oligosaccharyl transferase
oligosaccharyltransferase
oligosaccharyltransferase complex
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oligosaccharyltransferase, dolichyldiphosphoryloligosaccharide-protein
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-
-
-
OST
OSTC(I)
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multiple distinct protein complexes are detected. OSTC(I) is the major complex
OTase
PglB
STT3 protein
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
AglB
archaeal homolog to bacterial PglB and eukaryotic Stt3
oligosaccharide transferase
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-
-
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OST
-
-
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
dolichyl diphosphooligosaccharide + [protein]-L-asparagine = dolichyl diphosphate + a glycoprotein with the oligosaccharide chain attached by N-beta-D-glycosyl linkage to a protein L-asparagine
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REACTION TYPE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
hexosyl group transfer
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-
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-
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PATHWAY SOURCE
PATHWAYS
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SYSTEMATIC NAME
IUBMB Comments
dolichyl-diphosphooligosaccharide:protein-L-asparagine N-beta-D-oligopolysaccharidotransferase
Occurs in eukaryotes that form a glycoprotein by the transfer of a glucosyl-mannosyl-glucosamine polysaccharide to the side-chain of an L-asparagine residue in the sequence -Asn-Xaa-Ser- or -Asn-Xaa-Thr- (Xaa not Pro) in nascent polypeptide chains. The basic oligosaccharide is the tetradecasaccharide Glc3Man9GlcNAc2 (for diagram {polysacc/Dol14}). However, smaller oligosaccharides derived from it and oligosaccharides with additional monosaccharide units attached may be involved. See ref [2] for a review of N-glycoproteins in eukaryotes. Man3GlcNAc2 seems to be common for all of the oligosaccharides involved with the terminal N-acetylglucosamine linked to the protein L-asparagine. Occurs on the cytosolic face of the endoplasmic reticulum. The dolichol involved normally has 14-21 isoprenoid units with two trans double-bonds at the omega end, and the rest of the double-bonds in cis form.
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CAS REGISTRY NUMBER
COMMENTARY
75302-32-8
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SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
COMMENTARY
(Substrate)
(Substrate)
LITERATURE
(Substrate)
(Substrate)
COMMENTARY
(Product)
(Product)
LITERATURE
(Product)
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
biantennary Man5GlcNAc2 dolichyl disphosphate + VSG221 coat glycoprotein
dolichyl disphosphate + ?
-
selective transfer of TbSTT3A to acidic to neutral regions of polypeptides, responsible for all paucimannose and complex N-glycans in Trypanosoma brucei glycoproteins
-
-
?
biantennary Man5GlcNAc2 dolichyl disphosphate + VSG221 coat glycoprotein
dolichyl disphosphate + protein with oligosaccharide attached to protein L-asparagine
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selective transfer of TbSTT3A to acidic to neutral regions of polypeptides, responsible for all paucimannose and complex N-glycans in Trypanosoma brucei glycoproteins
-
-
?
Campylobacter jejuni heptasaccharide bound to undecaprenyl diphosphate + pilin
undecaprenyl diphosphate + glycosylated pilin
-
alpha-1,3-linked sugar, in vivo in Escherichia coli
-
-
?
crude lipid-linked oligosaccharide donors from Campylobacter jejuni + carboxytetramethylrhodamine-Ala-Asp-Gln-Asn-Ala-Thr-Tyr-Lys
dolichyl disphosphate + carboxytetramethylrhodamine-Ala-(oligosaccharidyl) Asp-Gln-Asp-Ala-Thr-Tyr
dolichyl diphosphooligosaccharide + Ala-Leu-Glu-Asn-Ala-Thr-Arg-NH2
?
-
-
-
-
?
dolichyl diphosphooligosaccharide + asparagine-asparagine-threonine-NH2 acceptor peptide
dolichyl disphosphate + protein with oligosaccharide attached to protein L-asparagine
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-
-
?
dolichyl diphosphooligosaccharide + benzoyl-Asn-Leu-Thr-N-methyl-threonine
?
-
-
-
-
?
dolichyl diphosphooligosaccharide + carboxypeptidase Y (CPY)
dolichyl disphosphate + oligosaccharidyl-(carboxypeptidase Y)
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free enzyme
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-
?
dolichyl diphosphooligosaccharide + diphenyl-Ala-Leu-Glu-Asn-Ala-Thr-Arg-NH2
?
-
-
-
-
?
dolichyl diphosphooligosaccharide + diphenyl-AlaLeu-Glu-Asn-Ala-Thr-Arg-NH2
?
-
-
-
-
?
dolichyl diphosphooligosaccharide + N-benzoyl-Asn-Gly-D-allo-Thr-NHCH3
?
-
-
-
-
?
dolichyl diphosphooligosaccharide + N-benzoyl-Asn-Gly-L-threo-beta-hydroxynorvaline-NHCH3
?
-
-
-
-
?
dolichyl diphosphooligosaccharide + N2-acetyl-L-asparaginyl-4-benzoyl-L-phenylalanyl-L-tyrosinamide
dolichyl diphosphate + ?
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + a glycoprotein with the oligosaccharide chain attached by N-glycosyl linkage to protein L-asparagine
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + glycoprotein with the oligosaccharide chain attached by N-glycosyl-linkage to protein L-asparagine
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + oligosaccaharidyl-L-Asn protein
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl disphosphate + protein with oligosaccharide attached to protein L-asparagine
dolichyl diphosphooligosaccharide + [protein]-L-asparagine
dolichyl diphosphate + a glycoprotein with the oligosaccharide chain attached by N-beta-D-glycosyl linkage to a protein L-asparagine
dolichyl diphosphooligosaccharide + [protein]-L-asparagine
dolichyl diphosphate + [protein]-L-asparagine-N-oligosaccharide
dolichyl diphosphooligosaccharide + [protein]-L-asparagine
dolichyl diphosphate + [protein]-L-asparagine-oligosaccharide
dolichyl diphosphooligosaccharide + [protein]-L-asparagine
dolichyl diphosphate + [protein]-N-oligosaccharidyl-L-asparagine
dolichyl monophosphate GlcNAc-Glc-2,3-diNAcA + [protein]-L-asparagine
?
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-
-
-
?
dolichyl-diphosphochitobiose-Man1 + Tyr-Asn-Leu-Thr-Ser-Val
?
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-
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-
?
dolichyl-diphosphochitobiose-Man9 + Nalpha-Ac-Asn-Tyr-Thr-NH2
?
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-
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-
?
dolichyl-diphosphochitobiose-Man9Glc3 + alpha-Ac-Asn-Tyr-Thr-NH2
?
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-
-
-
?
dolichyl-diphosphochitobiose-Man9Glc3 + Nalpha-Ac-Asn-Lys(Nepsilon-p-azidobenzoyl)-Thr-NH2
?
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-
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-
?
dolichyl-diphosphochitobiose-Man9Glc3 + Tyr-Asn-Leu-Thr-Ser-Val
?
-
-
-
-
?
Escherichia coli group 1 K30 capsule antigen bound to undecaprenyl diphosphate + pilin
undecaprenyl diphosphate + glycosylated pilin
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in vivo in Escherichia coli
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-
?
Escherichia coli O16 antigen bound to undecaprenyl diphosphate + pilin
undecaprenyl diphosphate + glycosylated pilin
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alpha-1,6-linked Glc with GlcNAc, in vivo in Escherichia coli
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-
?
Escherichia coli O2 antigen bound to undecaprenyl diphosphate + pilin
undecaprenyl diphosphate + glycosylated pilin
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rhamnose beta-1,4-linked sugar, in vivo in Escherichia coli
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-
?
Escherichia coli O7 antigen bound to undecaprenyl diphosphate + pilin
undecaprenyl diphosphate + glycosylated pilin
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beta-1,3-linked sugar, in vivo in Escherichia coli
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-
?
Escherichia coli O86 antigen bound to farnesyl diphosphate + pilin
farnesyl diphosphate + glycosylated pilin
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pentasaccharide attached to other lipid carrier, in vitro, 500 mM Tris-HCl containing 1 M sucrose and 10 mM MnCl2, pH7.5, 30°C
-
-
?
GalNAc-N,N'-diacetyl-bacillosamine-PP-undecaprenyl + acetyl-DFNAT-(4-nitrophenylalanine)-NH2
?
-
-
-
-
?
GalNAc-N,N'-diacetyl-bacillosamine-PP-undecaprenyl + acetyl-DFNVT-(4-nitrophenylalanine)-NH2
?
-
-
-
-
?
GalNAc-N,N'-diacetyl-bacillosamine-PP-undecaprenyl + acetyl-DQNAT-(4-nitrophenylalanine)-NH2
?
-
-
-
-
?
GalNAc-N,N'-diacetyl-bacillosamine-PP-undecaprenyl + acetyl-DVNAS-(4-nitrophenylalanine)-NH2
?
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-
-
-
?
GalNAc-N,N'-diacetyl-bacillosamine-PP-undecaprenyl + acetyl-DVNAT-(4-nitrophenylalanine)-NH2
?
-
-
-
-
?
GalNAc-N,N'-diacetyl-bacillosamine-PP-undecaprenyl + acetyl-DVNVT-(4-nitrophenylalanine)-NH2
?
-
-
-
-
?
GalNAc-N,N'-diacetyl-bacillosamine-PP-undecaprenyl + acetyl-EVNAT-(4-nitrophenylalanine)-NH2
?
-
-
-
-
?
Glc3Man9GlcNAc2 dolichyl diphosphate + protein L-asparagine
?
-
-
-
-
?
Glc3Man9GlcNAc2 dolichyl disphosphate + GAYNSTSV
dolichyl disphosphate + GAY-(Glc3Man9GlcNAc2)NSTSV
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microsomes as enzyme source, STT3-1, increase in activity from 51 to 82% when the yeast SST3 expression is turned off, when yeast SST3 is active, only slight change in activity to 103%
-
-
?
Man5GlcNAc2 dolichyl diphosphate + GAYNSTSV
dolichyl diphosphate + GAY-(Man5GlcNAc2)NSTSV
-
microsomes as enzyme source, STT3-1, increase in activity from 34 to 109% when the yeast SST3 expression is turned off, when yeast SST3 is active, increase in activity to 115%
-
-
?
Man6GlcNAc2 dolichyl diphosphate + GAYNSTSV
dolichyl diphosphate + GAY-(Man6GlcNAc2)NSTSV
-
microsomes as enzyme source, STT3-1, increase in activity from 46 to 151% when the yeast SST3 expression is turned off, when yeast SST3 is active, increase in activity to 173%
-
-
?
Man9GlcNAc2 dolichyl disphosphate + GAYNSTSV
dolichyl disphosphate + GAY-(Man9GlcNAc2)NSTSV
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microsomes as enzyme source, STT3-1, increase in activity from 54 to 172% when the yeast SST3 expression is turned off, when yeast SST3 is active, increase in activity to 202%
-
-
?
N-acetyl-D-galactosaminyl-alpha-(1->3)-N,N'-diacetyl-alpha-D-bacillosaminyl-diphospho-tritrans,heptacis-undecaprenol + KDFNVSKA
tritrans,heptacis-undecaprenyl diphosphate + Lys-Asp-Phe-N4-[N-acetyl-D-galactosaminyl-alpha-(1->3)-N,N'-diacetyl-beta-D-bacillosaminyl]-Asn-Val-Ser-Lys-Ala
-
-
-
-
?
N-acetyl-D-glucosamine + glycoprotein bound to polysaccharide cell wall
?
-
glycoproteins as substrates are P15703, O13547, P53301, P32623, P28319, P38248, P22146, Q03655, Q08193, P38616
-
-
?
pentaprenyl diphospho-N-acetyl-D-galactosamine + [protein]-L-asparagine
pentaprenyl diphosphate + [protein]-N-(N-acetyl-D-galactosaminyl)-L-asparagine
PglB can utilize shorter polyisoprenol (pentaprenol) as the lipid carrier, albeit with reduced efficiency
-
-
?
peptidoglycan bound to undecaprenyl diphosphate + pilin
undecaprenyl diphosphate + glycosylated pilin
-
transfer of subunit of the peptidoglycan petapeptide, no transfer of the complete peptidoglycan is observed, in vivo in Salmonella enterica
-
-
?
Pseudomonas aeruginosa O11 antigen bound to undecaprenyl diphosphate + pilin
undecaprenyl diphosphate + glycosylated pilin
-
FucNac, in vivo in Escherichia coli
-
-
?
Salmonella enterica O antigen bound to undecaprenyl diphosphate + pilin
undecaprenyl diphosphate + glycosylated pilin
-
in vivo in Escherichia coli
-
-
?
Salmonella typhimurium LT2 antigen bound to undecaprenyl diphosphate + pilin
undecaprenyl diphosphate + glycosylated pilin
-
in vivo in Escherichia coli, in vivo in Salmonella enterica serovar Typhimurium LT2 strain
-
-
?
triantennary Man9GlcNAc2 dolichyl disphosphate + VSG221 coat glycoprotein
dolichyl disphosphate + protein with oligosaccharide attached to protein L-asparagine
-
selective transfer of TbSTT3B to neutral to basic regions of polypeptides responsible for most or all oligomannose N-glycans in Trypanosoma brucei glycoproteins
-
-
?
undecaprenyl diphospho-N-acetyl-D-galactosamine + [protein]-L-asparagine
undecaprenyl diphosphate + [protein]-N-(N-acetyl-D-galactosaminyl)-L-asparagine
PglB is solely responsible for the oligosaccharyltransferase activity. PglB can transfer a monosaccharide, e.g. GalNAc to a peptide acceptor. PglB exhibits relaxed sugar substrate specificity
-
-
?
crude lipid-linked oligosaccharide donors from Campylobacter jejuni + carboxytetramethylrhodamine-Ala-Asp-Gln-Asn-Ala-Thr-Tyr-Lys
dolichyl disphosphate + carboxytetramethylrhodamine-Ala-(oligosaccharidyl) Asp-Gln-Asp-Ala-Thr-Tyr
37°C, 50 mM Tris-HCl, pH 7.5
-
-
?
crude lipid-linked oligosaccharide donors from Campylobacter jejuni + carboxytetramethylrhodamine-Ala-Asp-Gln-Asn-Ala-Thr-Tyr-Lys
dolichyl disphosphate + carboxytetramethylrhodamine-Ala-(oligosaccharidyl) Asp-Gln-Asp-Ala-Thr-Tyr
-
37°C, 50 mM Tris-HCl, pH 7.5
-
-
?
dolichyl diphosphate-di-N-acetylchitobiose + Tyr-Asn-Leu-Thr-Ser-Val
?
-
-
-
-
?
dolichyl diphosphate-di-N-acetylchitobiose + Tyr-Asn-Leu-Thr-Ser-Val
?
-
-
-
-
?
dolichyl diphosphochitobiose-(mannosyl)9-(glucosyl)3 + synthetic hexapeptide
?
-
-
-
-
?
dolichyl diphosphochitobiose-(mannosyl)9-(glucosyl)3 + synthetic hexapeptide
?
-
-
-
-
?
dolichyl diphosphochitobiose-(mannosyl)9-(glucosyl)3 + synthetic hexapeptide
?
-
glycosyl-donors are also dolichyl diphosphochitobiose or dolichyl diphospho-chitobiose-mannose, no substrates are dolichyl diphosphochitobiose-(mannosyl)9 or dolichyl diphospho-N-acetyl-D-glucosamine
-
-
?
dolichyl diphosphochitobiose-(mannosyl)9-(glucosyl)3 + synthetic hexapeptide
?
-
e.g. Tyr-Asn-Leu-Thr-Ser-Val
-
-
?
dolichyl diphosphooligosaccharide + N2-acetyl-L-asparaginyl-4-benzoyl-L-phenylalanyl-L-tyrosinamide
dolichyl diphosphate + ?
-
-
-
-
?
dolichyl diphosphooligosaccharide + N2-acetyl-L-asparaginyl-4-benzoyl-L-phenylalanyl-L-tyrosinamide
dolichyl diphosphate + ?
-
-
-
-
?
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + a glycoprotein with the oligosaccharide chain attached by N-glycosyl linkage to protein L-asparagine
-
DQNAT is the optimal acceptor substrate. PglB is not capable of utilizing glycosyl donors such as dolichyl-pyrophosphatechitobiose
-
-
?
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + a glycoprotein with the oligosaccharide chain attached by N-glycosyl linkage to protein L-asparagine
-
the enzyme utilizes the in vivo oligosaccharide donor Glc3Man9GlcNAc2-PP-Dol in preference to certain larger and/or smaller oligosaccharide donors
-
-
?
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + a glycoprotein with the oligosaccharide chain attached by N-glycosyl linkage to protein L-asparagine
-
ribophorin I can regulate the delivery of precursor proteins to the oligosaccharyltransferase complex by capturing substrates and presenting them to the catalytic core
-
-
?
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + a glycoprotein with the oligosaccharide chain attached by N-glycosyl linkage to protein L-asparagine
-
PglL is able to transfer diverse oligo- and polysaccharides
-
-
?
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + a glycoprotein with the oligosaccharide chain attached by N-glycosyl linkage to protein L-asparagine
-
PilO activity is restricted to short oligosaccharides
-
-
?
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + a glycoprotein with the oligosaccharide chain attached by N-glycosyl linkage to protein L-asparagine
-
the enzyme utilizes the in vivo oligosaccharide donor Glc3Man9GlcNAc2-PP-Dol in preference to certain larger and/or smaller oligosaccharide donors
-
-
?
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + glycoprotein with the oligosaccharide chain attached by N-glycosyl-linkage to protein L-asparagine
-
-
-
?
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + glycoprotein with the oligosaccharide chain attached by N-glycosyl-linkage to protein L-asparagine
-
-
-
?
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + glycoprotein with the oligosaccharide chain attached by N-glycosyl-linkage to protein L-asparagine
-
-
-
?
dolichyl diphosphooligosaccharide + protein L-asparagine
dolichyl diphosphate + glycoprotein with the oligosaccharide chain attached by N-glycosyl-linkage to protein L-asparagine