Pyridoxal Dependent Decarboxylase Domain Containing Protein 1 (PDXDC1)

PDXDC1 is a pyridoxal dependent decarboxylase belonging to the decarboxylase group II family. Pyridoxal 5-phosphate is a coenzyme for a number of enzymes which catalyse reactions at Ca of amino acid substrates including transaminases, decarboxylases and serine hydroxymethyltransferase. Aspartate aminotransferase, and the results of stereochemical and mechanistic studies for decarboxylases and serine hydroxymethyltransferase, an active-site structure for the decarboxylase group is constructed. The structure of the active-site is further refined through active-site pyridoxyllysine peptide sequence comparison and a 3-D catalytic mechanism for the L-a-amino acid decarboxylases is proposed. The chemistry of serine hydroxymethyltransferase is re-examined in the light of the proposed decarboxylase mechanism.