Cloned (Comment) | Organism |
---|---|
expression in Escherichia coli BLR with pET-28a | Entamoeba histolytica |
Crystallization (Comment) | Organism |
---|---|
native and in complex with its product L-cysteine, 50 mM Tris buffer, pH 8.0, with 150 mM NaCl, hanging drop method at 16°C, 2.3 M ammonium sulfate as precipitant for the complex with 5 mM cysteine in 100 mM Tris, pH 7.2, with increasing glycerol concentrations, diffraction data collection at -173°C | Entamoeba histolytica |
native protein at 1.86 A resolution, in complex with product cysteine at 2.4 A resolution. The dimeric interface lacks a chloride binding site. The N-terminal extension participates in dimeric interactions in a domain swapping manner. Sulfate is bound in the active site of the native structure, which is replaced by cysteine in the cysteine bound form | Entamoeba histolytica |
General Stability | Organism |
---|---|
extended dimeric interface interactions contribute to the stability of the dimer under physiological conditions | Entamoeba histolytica |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
O3-acetyl-L-serine + hydrogen sulfide | Entamoeba histolytica | in the absence of sulfide O3-acetyl-L-serine reacts with the cofactor pyridoxal 5'-phosphate to alpha-aminoacrylate intermediate | L-cysteine + acetate | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Entamoeba histolytica | - |
- |
- |
Entamoeba histolytica | O15570 | - |
- |
Purification (Comment) | Organism |
---|---|
- |
Entamoeba histolytica |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
O3-acetyl-L-serine + hydrogen sulfide | in the absence of sulfide O3-acetyl-L-serine reacts with the cofactor pyridoxal 5'-phosphate to alpha-aminoacrylate intermediate | Entamoeba histolytica | L-cysteine + acetate | - |
? |
Subunits | Comment | Organism |
---|---|---|
dimer | crystallization data | Entamoeba histolytica |
dimer | 2 * ?, determined by molecular replacement of crystal structure | Entamoeba histolytica |
Synonyms | Comment | Organism |
---|---|---|
EhOASS | - |
Entamoeba histolytica |
O-acetylserine sulfhydrylase | - |
Entamoeba histolytica |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
pyridoxal 5'-phosphate | gives the crystals a yellow color, covalently linked to Lys58, interaction with Gly236, Ser280, Pro307, cofactor orientation at the active site and absorbance maximum change upon binding of cysteine or methionine | Entamoeba histolytica |
General Information | Comment | Organism |
---|---|---|
physiological function | product cysteine plays an important role in the antioxidative defense mechanisms of the human parasite | Entamoeba histolytica |