Activating Compound | Comment | Organism | Structure |
---|---|---|---|
ADP | slight activation | Escherichia coli | |
AMPPNP | - |
Escherichia coli | |
ATP | - |
Escherichia coli | |
ATP | highly activating | Escherichia coli | |
dATP | highly activating | Escherichia coli | |
diphosphate | - |
Escherichia coli | |
additional information | the enzyme shows a mechanism of activation that is NTP-dependent, poor activation by UDP-alpha-D-glucose. The inclusion of MgCl2 in the reaction buffer reverses the NTP-dependent activation of UgdK-12, in a concentration-dependent manner. This is not specific to Mg2+ as a similar effect is found for other divalent cations, including Ca2+, Mn2+, Zn2+, and Ni2+. Monovalent cations do not affect UgdK-12 activity. Chelating the divalent cation with EDTA or EGTA restores the NTP-dependent activation of UgdK-12 | Escherichia coli | |
UDP | slight activation | Escherichia coli | |
UTP | best activating nucleotide triphosphate | Escherichia coli |
Cloned (Comment) | Organism |
---|---|
gene ugd, located near the colanic acid/group 1 CPS locus, recombinant overexpression of His6-tagged enzyme in Escherichia coli strain CWG876 | Escherichia coli |
gene ugd, located near the colanic acid/group 1 CPS locus, recombinant overexpression of His6-tagged full-length enzyme and truncated enzyme comprising residues 447-704 in Escherichia coli strain CWG876 | Escherichia coli |
Protein Variants | Comment | Organism |
---|---|---|
K323A | site-directed mutagenesis, the mutant shows altered kinetics compared to the wild-type enzyme | Escherichia coli |
additional information | enzyme Ugd from Escherichia coli K-12 can functionally replace enzyme Ugd from Escherichia coli serotype K30 in biosynthesis of K30 capsular polysaccharide | Escherichia coli |
R324A | site-directed mutagenesis, the mutant purifies in much lower amounts relative to wild-type and is prone to degradation and has negligible activity | Escherichia coli |
Y71F | site-directed mutagenesis, the mutant shows unaltered catalytic activity | Escherichia coli |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
additional information | the enzyme from serotype K30 is not inhibited by NAD+, in contrast to Escherichia coli K-12 | Escherichia coli | |
NAD+ | substrate inhibition, reversible by the addition of a nucleotide triphosphate, e.g. ATP, in the absence of kinase. Mutations in a previously identified UDP-glucuronic acid allosteric binding site decrease the binding affinity of the nucleotide triphosphate | Escherichia coli | |
UDP-alpha-D-glucuronate | slight product inhibition | Escherichia coli |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | Michaelis-Menten kinetics | Escherichia coli | |
0.31 | - |
NAD+ | pH 9.5, 37°C, recombinant wild-type enzyme | Escherichia coli | |
0.35 | 0.62 | NAD+ | pH 9.5, 37°C, recombinant wild-type enzyme, from different strains | Escherichia coli | |
0.35 | 0.62 | NAD+ | pH 9.5, 37°C, recombinant wild-type enzyme, with 0.025-1.0 mM ATP | Escherichia coli | |
0.43 | - |
NAD+ | pH 9.5, 37°C, recombinant mutant K323A | Escherichia coli | |
0.5 | - |
NAD+ | pH 9.5, 37°C, recombinant mutant Y71F | Escherichia coli |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
UDP-alpha-D-glucose + 2 NAD+ + H2O | Escherichia coli | - |
UDP-alpha-D-glucuronate + 2 NADH + 2 H+ | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | - |
several strains | - |
Escherichia coli | - |
serotype K30, several strains | - |
Posttranslational Modification | Comment | Organism |
---|---|---|
phosphoprotein | possible role of Ugd phosphorylation in the production of a constitutively expressed capsular polysaccharide, no role for phosphorylation in modulating activity of Ugd. Escherichia coli might contain two bacterial tyrosine kinases, analysis of kinase deletion mutants of Escherichia coli strains, overview | Escherichia coli |
phosphoprotein | tyrosine phosphorylation in the activation of Ugd of Escherichia coli K12. Possible role of Ugd phosphorylation in the production of a constitutively expressed capsular polysaccharide (CPS), no role for phosphorylation in modulating activity of Ugd. Escherichia coli might contain two bacterial tyrosine kinases, analysis of kinase deletion mutants of Escherichia coli strains, overview | Escherichia coli |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
UDP-alpha-D-glucose + 2 NAD+ + H2O | - |
Escherichia coli | UDP-alpha-D-glucuronate + 2 NADH + 2 H+ | - |
? |
Subunits | Comment | Organism |
---|---|---|
More | structural modelling of the enzyme in complex with NAD and uridine 5'-monophosphate, using structure of Ugd from Klebsiella pneumoniae in complex with UDPGA, PDB ID 3PJG, as template | Escherichia coli |
Synonyms | Comment | Organism |
---|---|---|
UDP-glucose dehydrogenase | - |
Escherichia coli |
Ugd | - |
Escherichia coli |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
37 | - |
assay at | Escherichia coli |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
2.7 | - |
NAD+ | pH 9.5, 37°C, recombinant mutant K323A | Escherichia coli | |
4.2 | - |
NAD+ | pH 9.5, 37°C, recombinant wild-type enzyme | Escherichia coli | |
5.4 | 7.1 | NAD+ | pH 9.5, 37°C, recombinant wild-type enzyme, from different strains | Escherichia coli | |
7.3 | - |
NAD+ | pH 9.5, 37°C, recombinant mutant Y71F | Escherichia coli | |
56.2 | - |
NAD+ | pH 9.5, 37°C, recombinant wild-type enzyme, with 0.025-1.0 mM ATP | Escherichia coli |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
9.5 | - |
assay at | Escherichia coli |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
NAD+ | - |
Escherichia coli |
General Information | Comment | Organism |
---|---|---|
additional information | enzyme Ugd from Escherichia coli K-12 can functionally replace enzyme Ugd from Escherichia coli serotype K30 in biosynthesis of K30 capsular polysaccharide | Escherichia coli |
physiological function | in Escherichia coli K-12, Ugd is important for biosynthesis of the environmentally regulated exopolysaccharide known as colanic acid, whereas in other Escherichia coli isolates, the same enzyme is required for production of the constitutive group 1 capsular polysaccharides, which act as virulence determinants | Escherichia coli |
physiological function | in Escherichia coli serotype K30, the enzyme is required for production of the constitutive group 1 capsular polysaccharides, which act as virulence determinants | Escherichia coli |