title: Free energy perturbation simulation on transition states and high-activity mutants of human butyrylcholinesterase for (-)-cocaine hydrolysis.
abstract: A unified computational approach based on free energy perturbation (FEP) simulations of transition states has been employed to calculate the mutation-caused shifts of the free energy change from the free enzyme to the rate-determining transition state for (-)-cocaine hydrolysis catalyzed by the currently most promising series of mutants of human butyrylcholinesterase (BChE) that contain the A199S/A328W/Y332G mutations. The FEP simulations were followed by Michaelis-Menten kinetics analysis determining the individual k(cat) and K(M) values missing for the A199S/F227A/A328W/Y332G mutant in this series. The calculated mutation-caused shifts of the free energy change from the free enzyme to the rate-determining transition state are in good agreement with the experimental kinetic data, demonstrating that the unified computational approach based on the FEP simulations of the transition states may be valuable for future computational design of new BChE mutants with a further improved catalytic efficiency against (-)-cocaine.
authors.affiliation: Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry, Central China Normal University, Wuhan 430079, PR China.
authors.forename: Wenchao
authors.initials: W
authors.lastname: Yang
authors.forename: Yongmei
authors.initials: Y
authors.lastname: Pan
authors.forename: Lei
authors.initials: L
authors.lastname: Fang
authors.forename: Daquan
authors.initials: D
authors.lastname: Gao
authors.forename: Fang
authors.initials: F
authors.lastname: Zheng
authors.forename: Chang-Guo
authors.initials: CG
authors.lastname: Zhan
mesh_terms: D019943:Amino Acid Substitution; D002091:Butyrylcholinesterase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D003042:Cocaine / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis; D007700:Kinetics; D056004:Molecular Dynamics Simulation; D050505:Mutant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D011487:Protein Conformation; D013816:Thermodynamics
chemical_list: D050505:Mutant Proteins; D002091:Butyrylcholinesterase; D003042:Cocaine