Phosphoserine aminotransferase (IPR022278)

Short name: Pser_aminoTfrase

Overlapping homologous superfamilies

Family relationships


Phosphoserine aminotransferase (PSAT) is involved in serine biosynthesis [PMID: 21902733, PMID: 16289358]. The enzyme catalyses the reversible conversion of 3-phosphohydroxypyruvate to L-phosphoserine. PSAT from Escherichia coli has been shown to be a homodimer of Mr79,000 with a conserved lysine that binds covalently to pyridoxal phosphate (PLP). PSAT is a vitamin B6-dependent enzyme and belongs to the alpha family of PLP enzymes. PSAT is also classified as a member of the aspartate aminotransferase family of PLP enzymes [PMID: 9914259]. According to the structural classification of PLP-dependent enzymes [PMID: 7670372], PSAT belongs to the pyridoxal phosphate (PLP)-dependent aspartate aminotransferase superfamily (fold I), where it is allocated to a separated subclass. The mechanism of action in all these enzymes is similar: PLP combines with an alpha-amino acid to form a compound called a Schiff base or aldimine intermediate, which, depending on the reaction, is the substrate in four kinds of reactions: transamination (movement of amino groups), racemization (redistribution of enantiomers), decarboxylation (removing COOH groups), and various side-chain reactions depending on the enzyme involved.

GO terms

Biological Process

GO:0006564 L-serine biosynthetic process

Molecular Function

GO:0004648 O-phospho-L-serine:2-oxoglutarate aminotransferase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.