Alanine racemase

Alanine racemase is an enzyme that catalyzes the reversible conversion of L-alanine to D-alanine. D-alanine is a critical component for the biosynthesis of peptidoglycan, which forms the structural framework of bacterial cell walls. The enzyme is found universally in prokaryotes but is absent from higher eukaryotes, making it an attractive target for antimicrobial drug development. It utilizes pyridoxal 5'-phosphate (PLP) as a cofactor. Inhibitors like D-cycloserine block peptidoglycan synthesis by preventing the production of D-alanine, leading to bacterial cell death. Because humans lack this enzyme entirely, selective inhibition offers high therapeutic potential with low host toxicity.

Inhibition of alanine racemase, preventing D-alanine production necessary for peptidoglycan synthesis.