1. Effect of electrostatic interaction on the mechanism of dehalogenation catalyzed by haloalkane dehalogenase.
- Author
-
Zhang, Yuhua, Chen, Dezhan, Zhang, Honghong, Liu, Jianbiao, Mi, Shizhen, and Zhang, Guiqiu
- Subjects
ELECTROSTATICS ,HALOALKANES ,CATALYSIS ,NUCLEOPHILIC reactions ,HYDROGEN bonding ,ENZYMATIC analysis ,CHLORINE ,QUANTUM chemistry - Abstract
Theoretical calculation has been carried out for the nucleophilic displacement reaction of 1,2-dichloroethane catalyzed by haloalkane dehalogenase. The results indicate that different hydrogen bond patterns of the oxyanion hole and the halide-stabilizing residues play an important role in the dehalogenation reaction. They cause concertedly an earlier transition state (TS) with the activation barrier of 16.60 kcal/mol. The stabilization effect of Trp125 and Trp175 on chlorine atom in the TS is larger than that of the reactant complex by 15.67 kcal/mol so that, they make contribution to the stabilization of the TS. Moreover, the reaction shows the enzymatic action can be attributed to a combination of reactant-state destabilization and transition-state electrostatic stabilization. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF