The C-terminal domain of Escherichia coli dihydrodipicolinate synthase (DHDPS) is essential for maintenance of quaternary structure and efficient catalysis.

Dihydrodipicolinate synthase (DHDPS) catalyses the first committed step in the biosynthesis of (S)-lysine, an essential constituent of bacterial cell walls. Escherichia coli DHDPS is homotetrameric, and each monomer contains an N-terminal (alpha/beta)(8)-barrel, responsible for catalysis and regulation, and three C-terminal alpha-helices, the function of which is unknown. This study investigated the C-terminal domain of E.