Application | Comment | Organism |
---|---|---|
medicine | in parasitic protists the L-cysteine biosynthetic pathway is present in contrast to mammals, therefore, enzymes in this pathway are a potential target for chemotherapeutic agents | Entamoeba histolytica |
Cloned (Comment) | Organism |
---|---|
PCR-amplification, expression of histidine tagged gene in Escherichia coli BL21 (DE3) pLysS, heat shock transformed | Entamoeba histolytica |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
L-cysteine | 0.03 mM, 0.5 mM, and 1 mM, strong inhibition, 5-500 microM L-cysteine in the presence of 0.5 mM L-serine inhibits the enzyme remarkably, much less but still significantly in the presence of 3 mM L-serine, 90% inhibition by 0.3 mM L-cysteine with 3 mM L-serine (as found in throphozoite culture), acetyl-CoA concentration influences the inhibitory efficiency as well; 0.5 mM inhibits by 75.3%, no inhibition with 0.03 mM, 1 mM not determined, 20% inhibition by 0.3 mM L-cysteine with 3 mM L-serine (as found in throphozoite culture); 1 mM, weak inhibition, no inhibition by 0.3 mM L-cysteine with 3 mM L-serine (as found in throphozoite culture) or at other L-cysteine concentrations from 10-1000 micoM in the presence of 3 mM L-serine | Entamoeba histolytica | |
additional information | no inhibition by 0.03 mM L-cystine, 0.5 mM D-cysteine, DL-homocysteine, DL-homoserine, and oxidized glutathione (reduced glutathione not determined); no inhibition with 0.03 and 0.5 mM L-cystine, 0.5 mM D-cysteine, DL-homocysteine, DL-homoserine, and N-acetyl-L-serine; no inhibition with 0.03 mM L-cystine, 0.5 mM D-cysteine, DL-homocysteine, DL-homoserine, N-acetyl-L-serine, and oxidized glutathione | Entamoeba histolytica | |
N-acetyl-L-cysteine | 1 mM weak inhibition; 1 mM, weak inhibition; 1 mM, weak inhibition | Entamoeba histolytica | |
N-acetyl-L-serine | 0.5 mM, weak inhibition | Entamoeba histolytica | |
oxidized glutathione | 0.5 mM, weak inhibition | Entamoeba histolytica | |
reduced glutathione | 0.5 mM weak inhibition; 0.5 mM, weak inhibition | Entamoeba histolytica |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.09 | - |
L-serine | SAT2, 50 mM Tris-HCl, pH 8.0, 0.1 mM acetyl-CoA, 25°C | Entamoeba histolytica | |
0.1 | - |
L-serine | SAT2, 50 mM Tris-HCl, pH 8.0, 0.1 mM acetyl-CoA, 25°C | Entamoeba histolytica | |
0.12 | - |
L-serine | 50 mM Tris-HCl, pH 8.0, 0.1 mM acetyl-CoA, 25°C | Entamoeba histolytica | |
0.2 | - |
acetyl-CoA | SAT2, 50 mM Tris-HCl, pH 8.0, 1 mM L-serine, 25°C | Entamoeba histolytica | |
0.25 | - |
acetyl-CoA | SAT2, 50 mM Tris-HCl, pH 8.0, 1 mM L-serine, 25°C | Entamoeba histolytica | |
0.55 | - |
acetyl-CoA | 50 mM Tris-HCl, pH 8.0, 1 mM L-serine, 25°C | Entamoeba histolytica |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
cytosol | immunofluorescence imaging with antiserum against recombinant protein, and indirectly deduced from missing N-terminal transit peptide | Entamoeba histolytica | 5829 | - |
cytosol | immunofluorescence imaging with antiserum against recombined protein, and indirectly deduced from missing N-terminal transit peptide | Entamoeba histolytica | 5829 | - |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
34400 | - |
calculated from sequence, 305 amino acids | Entamoeba histolytica |
34800 | - |
calculated from sequence, 311 amino acids | Entamoeba histolytica |
37000 | - |
SDS-PAGE, recombinant purified enzyme monomer with 2.6 kDa histidine tag | Entamoeba histolytica |
37400 | - |
SDS-PAGE, recombinant purified enzyme monomer with 2.6 kDa histidine tag | Entamoeba histolytica |
37700 | - |
calculated from sequence, 336 amino acids | Entamoeba histolytica |
40000 | - |
SDS-PAGE, recombinant purified enzyme monomer with 2.6 kDa histidine tag | Entamoeba histolytica |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
L-serine + acetyl-CoA | Entamoeba histolytica | - |
O-acetyl serine + CoA | subsequently, cysteine synthase forms L-cysteine from O-acetyl serine | ? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Entamoeba histolytica | - |
trophozoites of the clonal strain HM1: IMSS cl 6 | - |
Entamoeba histolytica | Q401L4 | trophozoites of the clonal strain HM1: IMSS cl 6 | - |
Entamoeba histolytica | Q401L5 | trophozoites of the clonal strain HM1: IMSS cl 6 | - |
Purification (Comment) | Organism |
---|---|
recombinant cells are centrifuged, pellet washed with PBS, pH 7.4, resuspended in lysis buffer (50 mM Tris-HCl, pH 8.0), incubated, sonicated, centrifuged, Ni2+ -NTA agarose column, washed with buffer (50 mM Tris-HCl, pH 8.0), eluted imidazole, SDS-PAGE, dialyzed with 50 mM Tris-HCl, pH 8.0, storage with 20% glycerol at -80°C | Entamoeba histolytica |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
additional information | - |
coupling reaction with cysteine synthase, 50 mM Tris-HCl, pH 8.0, 0.4 mM acetyl-CoA, 4 mM L-serine, 5 mM Na2S, 10 mM DTT, recombinant Entamoeba histolytica cysteine synthase 3, 37°C (amount of L-cysteine produced) | Entamoeba histolytica |
23.42 | - |
Vmax with acetyl-CoA, 50 mM Tris-HCl, pH 8.0, 1 mM L-serine, 25°C | Entamoeba histolytica |
27.77 | - |
Vmax with L-serine, 50 mM Tris-HCl, pH 8.0, 0.1 mM acetyl-CoA, 25°C | Entamoeba histolytica |
41.39 | - |
Vmax with L-serine, 50 mM Tris-HCl, pH 8.0, 0.1 mM acetyl-CoA, 25°C | Entamoeba histolytica |
65.75 | - |
Vmax with L-serine, 50 mM Tris-HCl, pH 8.0, 0.1 mM acetyl-CoA, 25°C | Entamoeba histolytica |
95.1 | - |
Vmax with acetyl-CoA, 50 mM Tris-HCl, pH 8.0, 1 mM L-serine, 25°C | Entamoeba histolytica |
176.8 | - |
Vmax with acetyl-CoA, 50 mM Tris-HCl, pH 8.0, 1 mM L-serine, 25°C | Entamoeba histolytica |
Storage Stability | Organism |
---|---|
-30°C or -80°C, 50 mM Tris-HCl, pH 8.0, 10-20% glycerol in small aliquots, fully active after more than 3 months | Entamoeba histolytica |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
L-serine + acetyl-CoA | - |
Entamoeba histolytica | O-acetyl serine + CoA | subsequently, cysteine synthase forms L-cysteine from O-acetyl serine | ? |
Subunits | Comment | Organism |
---|---|---|
monomer | - |
Entamoeba histolytica |
monomer | 1 * 34800, SDS-PAGE | Entamoeba histolytica |
monomer | 1 * 34400, SDS-PAGE | Entamoeba histolytica |
Synonyms | Comment | Organism |
---|---|---|
EhSAT1 | - |
Entamoeba histolytica |
EhSAT2 | - |
Entamoeba histolytica |
EhSAT3 | - |
Entamoeba histolytica |
SAT | - |
Entamoeba histolytica |
SAT3 | - |
Entamoeba histolytica |
serine acetyltransferase | - |
Entamoeba histolytica |
serine O-acetyltransferase | - |
Entamoeba histolytica |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
14.59 | - |
acetyl-CoA | 50 mM Tris-HCl, pH 8.0, 1 mM L-serine, 25°C | Entamoeba histolytica | |
17.31 | - |
L-serine | 50 mM Tris-HCl, pH 8.0, 0.1 mM acetyl-CoA, 25°C | Entamoeba histolytica | |
25.52 | - |
L-serine | 50 mM Tris-HCl, pH 8.0, 0.1 mM acetyl-CoA, 25°C | Entamoeba histolytica | |
43.83 | - |
L-serine | 50 mM Tris-HCl, pH 8.0, 0.1 mM acetyl-CoA, 25°C | Entamoeba histolytica | |
58.63 | - |
acetyl-CoA | 50 mM Tris-HCl, pH 8.0, 1 mM L-serine, 25°C | Entamoeba histolytica | |
117.9 | - |
acetyl-CoA | 50 mM Tris-HCl, pH 8.0, 1 mM L-serine, 25°C | Entamoeba histolytica |
Ki Value [mM] | Ki Value maximum [mM] | Inhibitor | Comment | Organism | Structure |
---|---|---|---|---|---|
0.0047 | - |
L-cysteine | competitive inhibition with L-serine but no inhibition with acetyl-CoA, 50 mM Tris-HCl, pH 8.0, 25°C | Entamoeba histolytica | |
0.02779 | - |
L-cysteine | competitive inhibition with L-serine, 50 mM Tris-HCl, pH 8.0, 25°C | Entamoeba histolytica | |
0.0947 | - |
L-cysteine | non-competitive inhibition with acetyl-CoA, 50 mM Tris-HCl, pH 8.0, 0.25 mM acetyl-CoA, 25°C | Entamoeba histolytica | |
0.46 | - |
L-cysteine | mixed inhibition with L-serine but no inhibition with acetyl-CoA, 50 mM Tris-HCl, pH 8.0, 0.5 mM L-serine, 25°C | Entamoeba histolytica |
Organism | Comment | pI Value Maximum | pI Value |
---|---|---|---|
Entamoeba histolytica | predicted from sequence | - |
5.7 |
Entamoeba histolytica | predicted from sequence | - |
5.99 |
Entamoeba histolytica | predicted from sequence | - |
6.63 |
IC50 Value | IC50 Value Maximum | Comment | Organism | Inhibitor | Structure |
---|---|---|---|---|---|
additional information | - |
0.03 mM inhibits by 97.3%, 0.5 mM by 95.4%, 1 mM by 98.5% | Entamoeba histolytica | L-cysteine | |
additional information | - |
0.5 mM inhibits by 75.3%, no inhibition with 0.03 mM | Entamoeba histolytica | L-cysteine | |
additional information | - |
0.5 mM weak inhibition (11.8%) | Entamoeba histolytica | N-acetyl-L-serine | |
additional information | - |
0.5 mM, 10.3% inhibition | Entamoeba histolytica | reduced glutathione | |
additional information | - |
0.5 mM, 10.7% inhibition | Entamoeba histolytica | reduced glutathione | |
additional information | - |
0.5 mM, 19.9% inhibition | Entamoeba histolytica | oxidized glutathione | |
additional information | - |
1 mM inhibits by 37.8%, no inhibition with 0.5 mM and 0.03 mM | Entamoeba histolytica | L-cysteine | |
additional information | - |
1 mM weak inhibition (25%) | Entamoeba histolytica | N-acetyl-L-cysteine | |
additional information | - |
1 mM, 13.3% inhibition | Entamoeba histolytica | N-acetyl-L-cysteine | |
additional information | - |
1 mM, 27.8% inhibition | Entamoeba histolytica | N-acetyl-L-cysteine |
General Information | Comment | Organism |
---|---|---|
metabolism | first step of the L-cysteine biosynthesis pathway | Entamoeba histolytica |
physiological function | the end product L-cysteine is essential for the synthesis of Fe-S proteins and it is necessary for growth, survival, attachment, and anti-oxidation | Entamoeba histolytica |