Glutamate racemase (GR (also MurI or RacE))

Glutamate racemase is an *essential bacterial enzyme* encoded by the *murI* gene, responsible for the racemization of L-glutamate to D-glutamate. D-glutamate is a critical component of bacterial peptidoglycan, conferring structural rigidity and resistance to protease degradation in the cell wall[1][2][4][5][6][7]. The enzyme operates through a cofactor-independent, two-step acid-base mechanism involving catalytic cysteine residues. Glutamate racemase is absent in humans, making it a prime target for antibacterial drug development[2][3][5]. In some bacteria, glutamate racemase also inhibits DNA gyrase, exhibiting a secondary regulatory role[1][4]. Inhibitors of this enzyme are actively explored for novel broad-spectrum antibiotics, although drug design faces challenges due to the enzyme's conformational flexibility and differences in active site architecture among bacterial species[2][3][6]. Resistance may arise if bacteria evolve alternative sources or pathways for D-glutamate production[7].\n\nThis summary reflects currently available scientific understanding based on biochemical, structural, and applied drug development studies of glutamate racemase[1][2][3][4][5][6][7][8].

Other names

MurIRacEGRglutamate racemase isozymes (RacE1, RacE2)D-glutamate forming enzyme

Competitive inhibition of glutamate racemase blocks D-glutamate formation, disrupting peptidoglycan synthesis and leading to impaired bacterial cell wall and death\nSome experimental inhibitors allosterically alter enzyme conformation