Type III Pyridoxal 5-phosphate (PLP)-Dependent Enzyme Diaminopimelate Decarboxylase
Diaminopimelate decarboxylase (DapDC, EC 126.96.36.199) participates in the last step of lysine biosynthesis. It converts meso-2,6-diaminoheptanedioate to L-lysine. It is a fold type III PLP-dependent enzyme that contains an N-terminal PLP-binding TIM-barrel domain and a C-terminal beta-sandwich domain, similar to bacterial alanine racemases. DapDC exists as homodimers with active sites that lie at the interface between the TIM barrel domain of one subunit and the beta-sandwich domain of the other subunit. Homodimer formation and the presence of the PLP cofactor are required for catalytic activity.