|Superclasses:||Reactions Classified By Conversion Type → Simple Reactions → Chemical Reactions|
|Reactions Classified By Substrate → Small-Molecule Reactions|
EC Number: 18.104.22.168
Enzymes and Genes:
|Arabidopsis thaliana col :||phosphoserine aminotransferase
|Escherichia coli K-12 substr. MG1655 :||3-phosphoserine aminotransferase
|Homo sapiens :||phosphoserine aminotransferase
|Methanocaldococcus jannaschii :||phosphoserine aminotransferase
|Methanosarcina acetivorans :||phosphoserine aminotransferase
|Rattus norvegicus :||phosphoserine aminotransferase 1
In Pathway: L-serine biosynthesis
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.
Mass balance status: Balanced.
Enzyme Commission Primary Name: phosphoserine transaminase
Enzyme Commission Synonyms: PSAT, phosphoserine aminotransferase, 3-phosphoserine aminotransferase, hydroxypyruvic phosphate-glutamic transaminase, L-phosphoserine aminotransferase, phosphohydroxypyruvate transaminase, phosphohydroxypyruvic-glutamic transaminase, 3-O-phospho-L-serine:2-oxoglutarate aminotransferase, SerC, PdxC, 3PHP transaminase
Standard Gibbs Free Energy (ΔrG'° in kcal/mol): 0.07583618 [Latendresse13]
Enzyme Commission Summary:
A pyridoxal-phosphate protein. This enzyme catalyses the second step in the phosphorylated pathway of serine biosynthesis in Escherichia coli [Pizer63, Zhao96]. It also catalyses the third step in the biosynthesis of the coenzyme pyridoxal 5-phosphate in Escherichia coli (using Reaction 2 above) [Zhao96]. In Escherichia coli, pyridoxal 5-phosphate is synthesized de novo by a pathway that involves EC 22.214.171.124 (erythrose-4-phosphate dehydrogenase), EC 126.96.36.1990 (4-phosphoerythronate dehydrogenase), EC 188.8.131.52 (phosphoserine transaminase), EC 184.108.40.2062 (4-hydroxythreonine-4-phosphate dehydrogenase), EC 220.127.116.11 (pyridoxine 5-phosphate synthase) and EC 18.104.22.168 (with pyridoxine 5-phosphate as substrate). Pyridoxal phosphate is the cofactor for both activities and therefore seems to be involved in its own biosynthesis [Drewke96]. Non-phosphorylated forms of serine and threonine are not substrates [Drewke96].
Relationship Links: BRENDA:EC:22.214.171.124 , ENZYME:EC:126.96.36.199 , IUBMB-ExplorEnz:EC:188.8.131.52 , UniProt:RELATED-TO:O34370 , UniProt:RELATED-TO:P10658 , UniProt:RELATED-TO:P19689 , UniProt:RELATED-TO:P23721 , UniProt:RELATED-TO:P33330 , UniProt:RELATED-TO:P44336 , UniProt:RELATED-TO:P62676 , UniProt:RELATED-TO:Q9CHW5 , UniProt:RELATED-TO:Q9PIH3
Drewke96: Drewke C, Klein M, Clade D, Arenz A, Muller R, Leistner E (1996). "4-O-phosphoryl-L-threonine, a substrate of the pdxC(serC) gene product involved in vitamin B6 biosynthesis." FEBS Lett 1996;390(2);179-82. PMID: 8706854
Zhao96: Zhao G, Winkler ME (1996). "A novel alpha-ketoglutarate reductase activity of the serA-encoded 3-phosphoglycerate dehydrogenase of Escherichia coli K-12 and its possible implications for human 2-hydroxyglutaric aciduria." J Bacteriol 1996;178(1);232-9. PMID: 8550422
Zhao96a: Zhao G, Winkler ME (1996). "4-Phospho-hydroxy-L-threonine is an obligatory intermediate in pyridoxal 5'-phosphate coenzyme biosynthesis in Escherichia coli K-12." FEMS Microbiol Lett 1996;135(2-3);275-80. PMID: 8595869
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