Activating Compound | Comment | Organism | Structure |
---|---|---|---|
CTP | activates | Streptococcus suis |
Cloned (Comment) | Organism |
---|---|
expression of wild-type and mutant enzymes in Escherichia coli BL21(DE3). SsneuA can restore both CMP-Neu5Ac synthetase and O-acetylesterase activities in complemented enzyme-deficient Escherichia coli strains, but the activities in the complemented strain are different from those in the wild-type Escherichia coli strain. However, the Streptococcus suis O-acetylesterase domain alone is unable to act on intracellular O-acetyl-Neu5Ac in Escherichia coli | Streptococcus suis |
Protein Variants | Comment | Organism |
---|---|---|
additional information | the mutant SsNeuAs truncated from 166 to 233 amino acids at the N-terminal a re active for pNP-Ac and their esterase activities are almost the same as the wild-type, only with one exception of the SsNeuA167-410, while the mutant SsNeuAs terminated at amino acid position of 227, 232, 233, 241, 247, 267, 283, 293, 312, 322, 338, 355 and 377 are inactive in CMP-Neu5Ac synthetase activity, even removal of 33 amino acid residues at C-terminal of the SsNeuA leads to a complete loss of CMP-Neu5Ac synthetase activity | Streptococcus suis |
S258A | site-directed mutagenesis | Streptococcus suis |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | activates | Streptococcus suis |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
CMP-O9-acetyl-N-acetylneuraminate + H2O | Streptococcus suis | SsNeuA is a bifunctional CMP-Neu5Ac synthetase/O-acetylesterase, which strictly de-O-acetylates CMP-O-acetyl-Neu5Ac | CMP-N-acetylneuraminate + acetate | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Streptococcus suis | - |
serotype 2 | - |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
1.8 | - |
purified recombinant 29 kDa O-acetylesterase fragment, pH 7.2, 37°C | Streptococcus suis |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
4-nitrophenyl acetate + H2O | - |
Streptococcus suis | 4-nitrophenol + acetate | - |
? | |
CMP-O9-acetyl-N-acetylneuraminate + H2O | SsNeuA is a bifunctional CMP-Neu5Ac synthetase/O-acetylesterase, which strictly de-O-acetylates CMP-O-acetyl-Neu5Ac | Streptococcus suis | CMP-N-acetylneuraminate + acetate | - |
? |
Subunits | Comment | Organism |
---|---|---|
More | SsNeuA is cleaved into two fragments, in which the 29-kDa protein recovers from SDS-PAGE still remaining its O-acetylesterase activity. The esterase domain is composed of 177 amino acid residues at C-terminal of the SsNeuA and its activity does not structurally depend on the CMP-Neu5Ac synthetase domain, overview | Streptococcus suis |
Synonyms | Comment | Organism |
---|---|---|
SsNeuA | - |
Streptococcus suis |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
25 | - |
substrate 4-nitrophenyl acetate, wild-type SsNeuA and mutant SsNeuA234-410 | Streptococcus suis |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
8 | 8.5 | substrate 4-nitrophenyl acetate, wild-type SsNeuA and mutant SsNeuA234-410 | Streptococcus suis |
General Information | Comment | Organism |
---|---|---|
additional information | SsNeuAc contains a asignature consensus sequence for serine esterase, Gly-Xaa-Ser-Xaa-Gly, is found within the C-terminal half | Streptococcus suis |
physiological function | the O-acetylesterase is probably essential for the synthesis of capsular Neu5Ac in Streptococcus suis | Streptococcus suis |