title: Modification and simulation of Rhizomucor miehei lipase: the influence of surficial electrostatic interaction on enantioselectivity.
abstract: Surface residues have a significant impact on the enantioselectivity of lipases. But the molecular basis of this has never been explained. In this work, transition state complexes of Rhizomucor miehei lipase (RmL) and (R)- or (S)-n-butyl 2-phenxypropinate were studied using molecular dynamics. According to comparison between B-factor of the two simulated complexes, the β 1-β 2 loop and α 2 helix were considered the enantioselectivity-determining domains of RmL. Interaction analysis of these domains suggested an Asp(61)-Arg(86) electrostatic interaction linking the loop and helix strongly impacting enantioselectivity of RmL. Modification of Arg(86) by 1, 2-cyclohexanedione weakening this interaction decreased the E ratio from 6 to 1, modification by 1-iodo-2, 3-butanedione covalently bonding Asp(61) and Arg(86) strengthening the interaction increased the E ratio to 45. Dynamics simulation and energy calculation of the modified lipases also displayed corresponding decreases or increases of enantioselectivity.
authors: Department of Chemical and Biological Engineering, Institute of Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
authors: Gang
authors: G
authors: Xu
authors: Xiao
authors: X
authors: Meng
authors: Lin-Jie
authors: LJ
authors: Xu
authors: Li
authors: L
authors: Guo
authors: Jian-Ping
authors: JP
authors: Wu
authors: Li-Rong
authors: LR
authors: Yang
mesh_terms: D008049:Lipase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D050505:Mutant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D020103:Rhizomucor / Q000201:enzymology* / Q000235:genetics; D055672:Static Electricity; D013379:Substrate Specificity; D013499:Surface Properties
chemical_list: D050505:Mutant Proteins; D008049:Lipase