EC Number | Activating Compound | Comment | Organism | Structure |
---|---|---|---|---|
4.2.1.22 | S-adenosyl-L-methionine | AdoMet is a V-type allosteric activator | Homo sapiens |
EC Number | Application | Comment | Organism |
---|---|---|---|
4.2.1.22 | analysis | development of a LC-MS/MS and HPLC methods to simultaneously measure formation of thioethers and hydrogen sulfide from mixtures of cystathionine beta-synthase substrates | Homo sapiens |
EC Number | KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|---|
4.2.1.22 | 1 | - |
L-homocysteine | synthesis of L-cystathionine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 1.04 | - |
L-homocysteine | synthesis of L-cystathionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 1.27 | - |
L-serine | cosubstrate H2S, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 1.32 | - |
L-serine | cosubstrate H2S, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 1.41 | - |
L-serine | synthesis of L-cystathionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 2.13 | - |
L-serine | synthesis of L-cystathionine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 4.31 | - |
L-homocysteine | cosubstrate L-cysteine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 4.48 | - |
L-homocysteine | cosubstrate L-cysteine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 4.7 | - |
H2S | cosubstrate L-serine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 5.02 | - |
H2S | cosubstrate L-serine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 8.11 | - |
L-cysteine | cosubstrate H2O, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 8.41 | - |
L-cysteine | cosubstrate H2O, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 13.41 | - |
L-cysteine | cosubstrate L-homocysteine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 15.92 | - |
L-cysteine | cosubstrate L-homocysteine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens |
EC Number | Organism | UniProt | Comment | Textmining |
---|---|---|---|---|
4.2.1.22 | Homo sapiens | P35520 | - |
- |
EC Number | Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|---|
4.2.1.22 | L-cysteine | - |
Homo sapiens | H2S + L-serine | - |
? | |
4.2.1.22 | L-cysteine + L-homocysteine | - |
Homo sapiens | L-cystathionine + H2S | - |
? | |
4.2.1.22 | L-cysteine + L-serine | - |
Homo sapiens | lanthionine + H2O | - |
? | |
4.2.1.22 | L-serine + H2S | - |
Homo sapiens | L-cysteine | - |
? | |
4.2.1.22 | additional information | cysteine is able to partially compete with serine on CBS, thus leading to generation of appreciable amounts of H2S. The leading H2S-producing reaction is condensation of cysteine with homocysteine, while cysteine desulfuration plays a dominant role when cysteine is more abundant than serine and homocysteine is limited. The serine-to-cysteine ratio is the main determinant of CBS H2S productivity. Abundance of cysteine over serine, for example, in blood plasma, allows for up to 43% of CBS activity being responsible for H2S production, while excess of serine typical for intracellular levels effectively limited such activity to less than 1.5%. CBS also produces lanthionine from serine and cysteine | Homo sapiens | ? | - |
? |
EC Number | Synonyms | Comment | Organism |
---|---|---|---|
4.2.1.22 | CBS | - |
Homo sapiens |
EC Number | Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|---|
4.2.1.22 | 0.35 | - |
H2S | cosubstrate L-serine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 0.39 | - |
L-serine | cosubstrate H2S, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 0.62 | - |
L-serine | cosubstrate H2S, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 0.78 | - |
H2S | cosubstrate L-serine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 1.06 | - |
L-cysteine | cosubstrate H2O, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 1.41 | - |
L-cysteine | cosubstrate H2O, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 3.67 | - |
L-serine | cosubstrate L-homocysteine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 4.66 | - |
L-homocysteine | cosubstrate L-serine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 7.09 | - |
L-cysteine | cosubstrate L-homocysteine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 8.17 | - |
L-homocysteine | cosubstrate L-cysteine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 12.7 | - |
L-homocysteine | cosubstrate L-serine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 14.01 | - |
L-serine | cosubstrate L-homocysteine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 26.78 | - |
L-homocysteine | cosubstrate L-cysteine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 31.34 | - |
L-cysteine | cosubstrate L-homocysteine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens |
EC Number | kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|---|
4.2.1.22 | 0.07 | - |
H2S | cosubstrate L-serine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 0.13 | - |
L-cysteine | cosubstrate H2O, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 0.17 | - |
H2S | cosubstrate L-serine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 0.18 | - |
L-cysteine | cosubstrate H2O, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 0.28 | - |
L-serine | cosubstrate H2S, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 0.47 | - |
L-serine | cosubstrate H2S, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 0.53 | - |
L-cysteine | cosubstrate L-homocysteine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 1.93 | - |
L-homocysteine | cosubstrate L-cysteine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 1.98 | - |
L-cysteine | cosubstrate L-homocysteine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 2.63 | - |
L-serine | synthesis of L-cystathionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 4.61 | - |
L-homocysteine | synthesis of L-cystathionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 6.02 | - |
L-homocysteine | cosubstrate L-cysteine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 7.61 | - |
L-serine | synthesis of L-cystathionine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens | |
4.2.1.22 | 12.74 | - |
L-homocysteine | synthesis of L-cystathionine, presence of S-adenosyl-L-methionine, pH 7.4, 37°C | Homo sapiens |