Increased organophosphate scavenging in a butyrylcholinesterase mutant.

School of Life Sciences and The Biodesign Institute, Arizona State University, Tempe, AZ 85287-4501, USA.
Chemico-Biological Interactions (Impact Factor: 2.98). 05/2008; 175(1-3):376-9. DOI: 10.1016/j.cbi.2008.04.012
Source: PubMed

ABSTRACT Nicotiana benthamiana plant lines expressing a reengineered human butyrylcholinesterase (BChE) with enhanced cocaine hydrolase activity were created. Subsequent purification and biochemical analysis revealed that compared to wild-type butyrylcholinesterase, the cocaine hydrolase displayed increased affinity to the organophosphate (OP) pesticides paraoxon (6.8 4x 10(-10)M vs. 1.11 x 10(-8)M) and malaoxon (9.81 x 10(-8)M vs. 5.99 x 10(-7)M). Furthermore, the cocaine hydrolase retained identical anticholinesterase binding profiles for all other compounds tested. Thus we have demonstrated a potential large-scale production platform for a multivalent antidote for cocaine and anticholinesterase poisoning.

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