Cloned (Comment) | Organism |
---|---|
expressed in Escherichia coli NM522 with plasmid pRSM40 | Salmonella enterica subsp. enterica serovar Typhimurium |
Protein Variants | Comment | Organism |
---|---|---|
K120Q | mutation results in a shift in the tautomeric equilibrium toward the neutral enolimine and an increase in the rate of interconversion of the open and closed forms of the enzyme. A decrease in the rate of both half reactions reflects the stabilization of the external Schiff base. Role of K120 in helping to stabilize the closed conformation of the enzyme by participating in a new bond to the backbone carbonyl of A231 | Salmonella enterica subsp. enterica serovar Typhimurium |
K120Q | shift in the tautomeric equilibrium toward the neutral enolimine and an increase of the rate of interconversion of the open and closed forms of the enzyme, probably reflecting the stabilization of the external Schiff base | Salmonella enterica subsp. enterica serovar Typhimurium |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.07 | - |
5-thio-2-nitrobenzoate | mutant H52A, pH 6.5 | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.07 | - |
5-thio-2-nitrobenzoate | K120Q mutant with 9fold decrease compared to wild type, 100 mM MES, pH 6.5, 0.5 mM O3-acetyl-L-serine, 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.6 | - |
5-thio-2-nitrobenzoate | wild type, 100 mM HEPES, pH 7.0, 0.5 mM O3-acetyl-L-serine, 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
1 | - |
O-acetyl-L-serine | mutant H52A, pH 6.5 | Salmonella enterica subsp. enterica serovar Typhimurium | |
1 | - |
O3-acetyl-L-serine | K120Q mutant with 15fold decrease compared to wild type, 100 mM MES, pH 6.5, 50 microM 5-thio-2-nitrobenzoate (TNB), 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
15 | - |
O3-acetyl-L-serine | wild type, 100 mM HEPES, pH 7.0, 50 microM 5-thio-2-nitrobenzoate (TNB), 25°C | Salmonella enterica subsp. enterica serovar Typhimurium |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
O3-acetyl-L-serine + hydrogen sulfide | Salmonella enterica subsp. enterica serovar Typhimurium | - |
L-cysteine + acetate | - |
? | |
O3-acetyl-L-serine + hydrogen sulfide | Salmonella enterica subsp. enterica serovar Typhimurium DW378 | - |
L-cysteine + acetate | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Salmonella enterica subsp. enterica serovar Typhimurium | - |
- |
- |
Salmonella enterica subsp. enterica serovar Typhimurium | - |
DW378 | - |
Salmonella enterica subsp. enterica serovar Typhimurium DW378 | - |
DW378 | - |
Purification (Comment) | Organism |
---|---|
Q-Sepharose and phenyl Sepharose column, active fractions are pooled and concentrated | Salmonella enterica subsp. enterica serovar Typhimurium |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
O-acetyl-L-serine + 5-thio-2-nitrobenzoate | - |
Salmonella enterica subsp. enterica serovar Typhimurium | ? + acetate | - |
? | |
O-acetyl-L-serine + 5-thio-2-nitrobenzoate | - |
Salmonella enterica subsp. enterica serovar Typhimurium DW378 | ? + acetate | - |
? | |
O3-acetyl-L-serine + 5-thio-2-nitrobenzoate | - |
Salmonella enterica subsp. enterica serovar Typhimurium | ? + acetate | - |
? | |
O3-acetyl-L-serine + 5-thio-2-nitrobenzoate | - |
Salmonella enterica subsp. enterica serovar Typhimurium DW378 | ? + acetate | - |
? | |
O3-acetyl-L-serine + hydrogen sulfide | - |
Salmonella enterica subsp. enterica serovar Typhimurium | L-cysteine + acetate | - |
? | |
O3-acetyl-L-serine + hydrogen sulfide | - |
Salmonella enterica subsp. enterica serovar Typhimurium DW378 | L-cysteine + acetate | - |
? |
Synonyms | Comment | Organism |
---|---|---|
O-acetylserine sulfhydrylase-A | - |
Salmonella enterica subsp. enterica serovar Typhimurium |
OASS-A | - |
Salmonella enterica subsp. enterica serovar Typhimurium |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.01 | - |
O3-acetyl-L-serine | turnover for mutant K120Q is decreased 56fold compared to wild type, 25°C, 100 mM HEPES, pH 7.0 | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.56 | - |
O3-acetyl-L-serine | wild type, 25°C, 100 mM HEPES, pH 7.0 | Salmonella enterica subsp. enterica serovar Typhimurium |
pH Minimum | pH Maximum | Comment | Organism |
---|---|---|---|
additional information | - |
pH-rate profiles for wild type and H152A mutant with O3-acetyl-L-serine and beta-chloro-L-alanine as substrates are similar, 100 mM concentrations of 2-(N-morpholino)ethanesulfonic acid (MES), pH 5.5-6.5, 3-(N-morpholino)propanesulfonic acid (MOPS), pH 7.0-7.5, N-(2-hydroxyethyl)piperazine-N'-2-ethanesulfonic acid (HEPES), pH 8.0, and 3-[[tris(hydroxymethyl)]amino]propanesulfonic acid (TAPS), pH 9.0, titrated with KOH | Salmonella enterica subsp. enterica serovar Typhimurium |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
pyridoxal 5'-phosphate | - |
Salmonella enterica subsp. enterica serovar Typhimurium |
General Information | Comment | Organism |
---|---|---|
metabolism | catalyzes the final step of the L-cysteine biosynthesis | Salmonella enterica subsp. enterica serovar Typhimurium |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.01 | - |
O3-acetyl-L-serine | K120Q mutant with 3.7fold decrease compared to wild type value, 100 mM MES, pH 6.5, 50 microM 5-thio-2-nitrobenzoate (TNB), 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.037 | - |
O3-acetyl-L-serine | wild type, 100 mM HEPES, pH 7.0, 50 microM 5-thio-2-nitrobenzoate (TNB), 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.141 | - |
5-thio-2-nitrobenzoate | K120Q mutant with 6.7fold decrease compared to wild type value, 100 mM MES, pH 6.5, 0.5 mM O3-acetyl-L-serine, 25°C | Salmonella enterica subsp. enterica serovar Typhimurium | |
0.95 | - |
5-thio-2-nitrobenzoate | wild type, 100 mM HEPES, pH 7.0, 0.5 mM O3-acetyl-L-serine, 25°C | Salmonella enterica subsp. enterica serovar Typhimurium |