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Information on EC 3.6.1.57 - UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose hydrolase
for references in articles please use BRENDA:EC3.6.1.57
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EC Tree 3 Hydrolases
3.6 Acting on acid anhydrides
3.6.1 In phosphorus-containing anhydrides
3.6.1.57 UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose hydrolase
IUBMB Comments
The enzyme is involved in biosynthesis of pseudaminic acid.
The enzyme appears in viruses and cellular organisms
Reaction Schemes
showSynonyms
udp-6-deoxy-altdinac hydrolase, more
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SYNONYM 
ORGANISM
UNIPROT
COMMENTARY 
LITERATURE
PseG
UDP-sugar hydrolase
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REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT
LITERATURE
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O = 2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
-
-
-
-
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PATHWAY SOURCE
PATHWAYS
MetaCyc
CMP-pseudaminate biosynthesis
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SYSTEMATIC NAME
IUBMB Comments
UDP-2,4-bis(acetamido)-2,4,6-trideoxy-beta-L-altropyranose hydrolase
The enzyme is involved in biosynthesis of pseudaminic acid.
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SUBSTRATE
PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
Reversibility
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O
2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
additional information
?
-
Substrates: molecular modeling identifies a His17-coordinated water molecule as the putative nucleophile and suggests the UDP-sugar substrate adopts a twist-boat conformation upon binding to PseG, enhancing the exposure of the anomeric bond cleaved and favoring inversion at C1
Products: -
Products: -
?
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O
2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
Substrates: the enzyme is involved in biosynthesis of pseudaminic acid (i.e. 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-alpha-L-manno-nonulosonic acid). The large value of the specificity constant suggests that hydrolysis of UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose is the biologically relevant reaction catalyzed by this enzyme
Products: -
Products: -
?
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O
2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
Substrates: the enzyme is involved in biosynthesis of pseudaminic acid (i.e. 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-alpha-L-manno-nonulosonic acid). Flagella of Campylobacter jejuni are important virulence determinants, whose proper assembly and function are dependent upon glycosylation at multiple positions by sialic acid-like sugars, such as 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-L-manno-nonulosonic acid (pseudaminic acid)
Products: -
Products: -
?
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O
2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
Substrates: catalyzes the reaction via a C-O bond cleavage mechanism with inversion of stereochemistry at C-1. No detectable activity with UDP-GlcNAc and an extremely low level of activity (less than 1%) with the biosynthetic precursor, UDP-4-amino-2,4,6-trideoxy-beta-L-AltNAc, indicating that the enzyme exhibits substrate specificity. A solvent derived oxygen atom is incorporated into the sugar during hydrolysis and is consistent with a C-O bond cleavage mechanism in which water directly attacks the anomeric carbon to displace UDP
Products: -
Products: -
?
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O
2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
Substrates: His17 functions as an active site base, thereby activating the nucleophilic water molecule for attack of the anomeric C-O bond of the UDP-sugar. No activity was observed with UDP-4-amino-4,6-dideoxy-beta-L-AltNAc or UDP-2,4-diacetamido-2,4,6-trideoxy-alpha-D-glucopyranose or UDP-2,4-diacetamido-bacillosamine
Products: -
Products: -
?
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O
2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
Substrates: -
Products: -
Products: -
?
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O
2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
Substrates: -
Products: -
Products: -
?
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NATURAL SUBSTRATE
NATURAL PRODUCT
REACTION DIAGRAM
ORGANISM
UNIPROT
LITERATURE
COMMENTARY
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
r=reversible
ir=irreversible
?=not specified
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O
2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O
2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
Substrates: the enzyme is involved in biosynthesis of pseudaminic acid (i.e. 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-alpha-L-manno-nonulosonic acid). The large value of the specificity constant suggests that hydrolysis of UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose is the biologically relevant reaction catalyzed by this enzyme
Products: -
Products: -
?
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O
2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
Substrates: the enzyme is involved in biosynthesis of pseudaminic acid (i.e. 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-alpha-L-manno-nonulosonic acid). Flagella of Campylobacter jejuni are important virulence determinants, whose proper assembly and function are dependent upon glycosylation at multiple positions by sialic acid-like sugars, such as 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-L-manno-nonulosonic acid (pseudaminic acid)
Products: -
Products: -
?
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O
2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
Substrates: -
Products: -
Products: -
?
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + H2O
2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose + UDP
Substrates: -
Products: -
Products: -
?
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METALS and IONS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
additional information
additional information
this enzyme is independent of the presence of divalent metal ions
additional information
-
this enzyme is independent of the presence of divalent metal ions
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INHIBITOR
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
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KM VALUE [mM]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.174
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.5, 37°C
0.25
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.3, 37°C, wild-type enzym
0.44
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.3, 37°C, mutant enzyme N255A
0.88
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.3, 37°C, mutant enzyme Y78F
1.3
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.3, 37°C, mutant enzyme H17N
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TURNOVER NUMBER [1/s]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.27
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.3, 37°C, mutant enzyme N255A
2.8
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.3, 37°C, mutant enzyme H17N
8.3
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.3, 37°C, mutant enzyme Y78F
25
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.3, 37°C, wild-type enzym
26.6
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.5, 37°C
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kcat/KM VALUE [1/mMs-1]
SUBSTRATE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
IMAGE
0.6
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.3, 37°C, mutant enzyme N255A
2.1
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.3, 37°C, mutant enzyme H17N
9.4
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.3, 37°C, mutant enzyme Y78F
100
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.3, 37°C, wild-type enzym
152.9
UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose
pH 7.5, 37°C
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pH OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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TEMPERATURE OPTIMUM
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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pI VALUE
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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ORGANISM
COMMENTARY
LITERATURE
UNIPROT
SEQUENCE DB
SOURCE
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LOCALIZATION
ORGANISM
UNIPROT
COMMENTARY
GeneOntology No.
LITERATURE
SOURCE
Highest Expressing Human Cell Lines
Cell Line LinksPlease wait a moment until the data is sorted. This message will disappear when the data is sorted.
GENERAL INFORMATION
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
physiological function
physiological function
the flagellin proteins in pathogenic bacteria such as Campylobacter jejuni and Helicobacter pylori are heavily glycosylated with the pseudaminic acid (i.e. 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-alpha-L-manno-nonulosonic acid). The presence of this posttranslational modification is absolutely required for assembly of functional flagella. Since motility is required for colonization, pseudaminic acid biosynthesis represents a virulence factor in these bacteria
physiological function
the enzyme is involved in biosynthesis of pseudaminic acid (i.e. 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-alpha-L-manno-nonulosonic acid). Flagella of Campylobacter jejuni are important virulence determinants, whose proper assembly and function are dependent upon glycosylation at multiple positions by sialic acid-like sugars, such as pseudaminic acid (i.e. 5,7-diacetamido-3,5,7,9-tetradeoxy-L-glycero-alpha-L-manno-nonulosonic acid)
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UNIPROT
ENTRY NAME
ORGANISM
NO. OF AA
NO. OF TRANSM. HELICES
MOLECULAR WEIGHT[Da]
SOURCE
SEQUENCE
LOCALIZATION PREDICTION
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable).
The reliability class of the localization prediction ranges from 1 (very reliable) to 5 (not reliable). PSEG_CAMJJ
Campylobacter jejuni subsp. jejuni serotype O:23/36 (strain 81-176)
274
0
31347
Swiss-Prot
-
PSEFG_HELPY
Helicobacter pylori (strain ATCC 700392 / 26695)
517
0
58934
Swiss-Prot
-
PSEG_CAMJE
Campylobacter jejuni subsp. jejuni serotype O:2 (strain ATCC 700819 / NCTC 11168)
274
0
31319
Swiss-Prot
-
B6JKQ3_HELP2
Helicobacter pylori (strain P12)
290
0
33058
TrEMBL
other Location (Reliability: 3)
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MOLECULAR WEIGHT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
32380
His6-tagged enzyme, electrospray ionization mass spectrometry
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SUBUNIT
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
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CRYSTALLIZATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
crystal structures of Campylobacter jejuni PseG in apo-form and as a complex with its UDP product at 1.8 and 1.85 A resolution.
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PROTEIN VARIANTS
ORGANISM
UNIPROT
COMMENTARY
LITERATURE
H17N
kcat/KM for UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose is 9.4% of the wild-type value
N255A
kcat/KM for UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose is 0.64% of the wild-type value
Y78F
kcat/KM for UDP-2,4-diacetamido-2,4,6-trideoxy-beta-L-altropyranose is 2.1% of the wild-type value
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PURIFICATION (Commentary)
ORGANISM
UNIPROT
LITERATURE
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CLONED (Commentary)
ORGANISM
UNIPROT
LITERATURE
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REF.
AUTHORS
TITLE
JOURNAL
VOL.
PAGES
YEAR
ORGANISM (UNIPROT)
PUBMED ID
SOURCE
Liu, F.; Tanner, M.E.
PseG of pseudaminic acid biosynthesis: a UDP-sugar hydrolase as a masked glycosyltransferase
J. Biol. Chem.
281
20902-20909
2006
Campylobacter jejuni (Q0P8U5), Campylobacter jejuni
brenda
Rangarajan, E.S.; Proteau, A.; Cui, Q.; Logan, S.M.; Potetinova, Z.; Whitfield, D.; Purisima, E.O.; Cygler, M.; Matte, A.; Sulea, T.; Schoenhofen, I.C.
Structural and functional analysis of Campylobacter jejuni PseG: a udp-sugar hydrolase from the pseudaminic acid biosynthetic pathway
J. Biol. Chem.
284
20989-21000
2009
Campylobacter jejuni (Q0P8U5)
brenda
Wahid, S.
Molecular modelling and structural analysis of the Helicobacter pylori pseudaminic acid biosynthesis UDP-sugar hydrolase PseG
Int. J. Pharm. Sci. Rev. Res.
41
168-172
2016
Helicobacter pylori (B6JKQ3), Helicobacter pylori P12 (B6JKQ3)
-
brenda
EXTERNAL LINKS (specific for EC-Number 3.6.1.57)
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