Download MendeleyA thermally stable form of bacterial cocaine esterase: a potential therapeutic agent for treatment of cocaine abuse.
Brim, R.L., Nance, M.R., Youngstrom, D.W., Narasimhan, D., Zhan, C.G., Tesmer, J.J., Sunahara, R.K., Woods, J.H.(2010) Mol Pharmacol 77: 593-600
- PubMed: 20086035
- DOI: https://doi.org/10.1124/mol.109.060806
- Primary Citation of Related Structures:
3IDA - PubMed Abstract:
Rhodococcal cocaine esterase (CocE) is an attractive potential treatment for both cocaine overdose and cocaine addiction. CocE directly degrades cocaine into inactive products, whereas traditional small-molecule approaches require blockade of the inhibitory action of cocaine on a diverse array of monoamine transporters and ion channels. The usefulness of wild-type (wt) cocaine esterase is hampered by its inactivation at 37 degrees C. Herein, we characterize the most thermostable form of this enzyme to date, CocE-L169K/G173Q. In vitro kinetic analyses reveal that CocE-L169K/G173Q displays a half-life of 2.9 days at 37 degrees C, which represents a 340-fold improvement over wt and is 15-fold greater than previously reported mutants. Crystallographic analyses of CocE-L169K/G173Q, determined at 1.6-A resolution, suggest that stabilization involves enhanced domain-domain interactions involving van der Waals interactions and hydrogen bonding. In vivo rodent studies reveal that intravenous pretreatment with CocE-L169K/G173Q in mice provides protection from cocaine-induced lethality for longer time periods before cocaine administration than wt CocE. Furthermore, intravenous administration (pretreatment) of CocE-L169K/G173Q prevents self-administration of cocaine in a time-dependent manner. Termination of the in vivo effects of CoCE seems to be dependent on, but not proportional to, its clearance from plasma as its half-life is approximately 2.3 h and similar to that of wt CocE (2.2 h). Taken together these data suggest that CocE-L169K/G173Q possesses many of the properties of a biological therapeutic for treating cocaine abuse but requires additional development to improve its serum half-life.
Organizational Affiliation:
Department of Pharmacology, University of Michigan Medical School, 1301 Medical Sciences Research Building III, 1150 W Medical Center Drive, Ann Arbor, MI 48109-0600, USA.
