New Delhi Metallo-β-LactamaseNew Delhi Metallo-β-Lactamase
The New Delhi metallo-β-lactamase () in complex with meropenem () demonstrates the mechanism in which the active site binds and hydrolyzed the a carbapenem, in this case meropenem.
Zn1 (coordinated by three histidine residues), acts as a major constituent of oxyanion hole to stabilize tetrahedral intermediate. It also acts as a Lewis acid for interaction with lactam carbonyl in Michaelis complex and acts to suppress the pKa of the hyrdolytic water to (~5-6) to facilitate it's nucleophilic role.
The active site contains key features for hydrolyzing carbapenems:
Zinc ion 1() is coordinated by three histidine residues:.
Zinc ion 2 () is coordinated by three residues: .