Effect of Ca(2+) on the activity and structure of α-glucosidase: inhibition kinetics and molecular dynamics simulations

J Biosci Bioeng. 2014 Jun;117(6):696-705. doi: 10.1016/j.jbiosc.2013.12.003. Epub 2014 Jan 20.


Understanding the mechanism of inhibition of α-glucosidase (EC is clinically important because of the involvement of this enzyme in type 2 diabetes mellitus. In this study, we conducted inhibition kinetics of α-glucosidase with Ca(2+) and 10-ns molecular dynamics simulations. We found that direct binding of Ca(2+) to the enzyme induced structural changes and inhibited enzyme activity. Ca(2+) inhibited α-glucosidase in a mixed-type reaction (Ki = 27.0 ± 2.0 mM) and directly induced the unfolding of α-glucosidase, which resulted in the exposure of hydrophobic residues. The simulations suggest that thirteen Ca(2+) ions may interact with α-glucosidase residues and that the Ca(2+) binding sites are associated with the structural changes in α-glucosidase. Our study provides insight into the mechanism of the Ca(2+)-induced structural changes in α-glucosidase and the inhibition of ligand binding. These results suggest that Ca(2+) could act as a potent inhibitor of α-glucosidase for the treatment of type 2 diabetes mellitus.

Keywords: Ca(2+); Inhibition kinetics; Molecular dynamics; Simulation; α-Glucosidase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Binding Sites
  • Calcium / chemistry*
  • Catalytic Domain
  • Diabetes Mellitus, Type 2 / complications
  • Diabetes Mellitus, Type 2 / enzymology
  • Enzyme Inhibitors / chemistry*
  • Glucosides / chemistry
  • Glycoside Hydrolase Inhibitors
  • Humans
  • Kinetics
  • Molecular Dynamics Simulation*
  • Molecular Sequence Data
  • Osteoporosis / drug therapy
  • Osteoporosis / etiology
  • Protein Binding
  • Protein Structure, Secondary
  • Saccharomyces cerevisiae Proteins / antagonists & inhibitors
  • Saccharomyces cerevisiae Proteins / chemistry*
  • alpha-Glucosidases / chemistry*


  • Enzyme Inhibitors
  • Glucosides
  • Glycoside Hydrolase Inhibitors
  • Saccharomyces cerevisiae Proteins
  • 4-nitrophenyl alpha-glucoside
  • alpha-Glucosidases
  • Calcium