Structural insights into human microsomal epoxide hydrolase by combined homology modeling, molecular dynamics simulations, and molecular docking calculations

Proteins. 2017 Apr;85(4):720-730. doi: 10.1002/prot.25251. Epub 2017 Feb 9.

Abstract

A new homology model of human microsomal epoxide hydrolase was derived based on multiple templates. The model obtained was fully evaluated, including MD simulations and ensemble-based docking, showing that the quality of the structure is better than that of only previously known model. Particularly, a catalytic triad was clearly identified, in agreement with the experimental information available. Analysis of intermediates in the enzymatic mechanism led to the identification of key residues for substrate binding, stereoselectivity, and intermediate stabilization during the reaction. In particular, we have confirmed the role of the oxyanion hole and the conserved motif (HGXP) in epoxide hydrolases, in excellent agreement with known experimental and computational data on similar systems. The model obtained is the first one that fully agrees with all the experimental observations on the system. Proteins 2017; 85:720-730. © 2016 Wiley Periodicals, Inc.

Keywords: clustering; ensemble-based docking; epilepsy; homology models; microsomal epoxide hydrolase.

MeSH terms

  • Amino Acid Sequence
  • Aspergillus niger / chemistry
  • Aspergillus niger / enzymology
  • Catalytic Domain
  • Conserved Sequence
  • Enzyme Inhibitors / chemistry*
  • Epoxide Hydrolases / antagonists & inhibitors
  • Epoxide Hydrolases / chemistry*
  • Epoxide Hydrolases / metabolism
  • Epoxy Compounds / chemistry*
  • Epoxy Compounds / metabolism
  • Humans
  • Kinetics
  • Microsomes, Liver / chemistry*
  • Microsomes, Liver / enzymology
  • Molecular Docking Simulation*
  • Molecular Dynamics Simulation
  • Protein Binding
  • Protein Interaction Domains and Motifs
  • Protein Structure, Secondary
  • Sequence Alignment
  • Streptomyces / chemistry
  • Streptomyces / enzymology
  • Structural Homology, Protein
  • Substrate Specificity
  • Valproic Acid / analogs & derivatives*
  • Valproic Acid / chemistry

Substances

  • Enzyme Inhibitors
  • Epoxy Compounds
  • Valproic Acid
  • styrene oxide
  • Epoxide Hydrolases
  • dipropylacetamide