Chen_2021_Angew.Chem.Int.Ed.Engl_60_21959

Benzoylecgonine (BZE) is the major toxic metabolite of cocaine, and is responsible for the long-term cocaine-induced toxicity due to its long residence time in humans. BZE is also the main contaminant following cocaine consumption, representing a risk to our environment and non-target organisms. Here, we identified the bacterial cocaine esterase (CocE) as a BZE-metabolizing enzyme (BZEase), which can degrade BZE into biological inactive metabolites (ecgonine and benzoic acid). CocE was redesigned by a reactant-state-based enzyme design theory. An encouraging mutant denoted as BZEase2, presented a >400-fold improved catalytic efficiency against BZE compared with wild-type (WT) CocE. In vivo , a single dose of BZEase2 (1 mg/kg, IV) could eliminate nearly all BZE within only two minutes, suggesting the enzyme have the potential for cocaine overdose treatment and BZE elimination in the environment by accelerating BZE clearance. The crystal structure of a designed BZEase was determined, providing additional insights in support of our simulation results.