Characterization of the sulfhydryl-sensitive site in the enzyme responsible for hydrolysis of 2-arachidonoyl-glycerol in rat cerebellar membranes

Chem Biol. 2005 Jun;12(6):649-56. doi: 10.1016/j.chembiol.2005.04.013.

Abstract

We have previously reported that the endocannabinoid, 2-arachidonoyl-glycerol (2-AG), is hydrolyzed in rat cerebellar membranes by monoglyceride lipase (MGL)-like enzymatic activity. The present study shows that, like MGL, 2-AG-degrading enzymatic activity is sensitive to inhibition by sulfhydryl-specific reagents. Inhibition studies of this enzymatic activity by N-ethylmaleimide analogs revealed that analogs with bulky hydrophobic N-substitution were more potent inhibitors than hydrophilic or less bulky agents. Interestingly, the substrate analog N-arachidonylmaleimide was found to be the most potent inhibitor. A comparison model of MGL was constructed to get a view on the cysteine residues located near the binding site. These findings support our previous conclusion that the 2-AG-degrading enzymatic activity in rat cerebellar membranes corresponds to MGL or MGL-like enzyme and should facilitate further efforts to develop potent and more selective MGL inhibitors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Arachidonic Acids / metabolism*
  • Binding Sites
  • Catalysis
  • Cell Membrane / enzymology
  • Cell Membrane / metabolism*
  • Cerebellum / cytology*
  • Cerebellum / enzymology*
  • Chloride Peroxidase / chemistry
  • Chloride Peroxidase / metabolism
  • Cysteine / metabolism
  • Endocannabinoids
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / pharmacology
  • Glycerides / metabolism*
  • Hydrolysis
  • Inhibitory Concentration 50
  • Male
  • Models, Molecular
  • Molecular Sequence Data
  • Molecular Structure
  • Monoacylglycerol Lipases / chemistry
  • Monoacylglycerol Lipases / metabolism
  • Protein Structure, Tertiary
  • Rats
  • Rats, Wistar
  • Sequence Alignment
  • Streptomyces lividans / enzymology
  • Structure-Activity Relationship
  • Sulfhydryl Compounds / chemistry*

Substances

  • Arachidonic Acids
  • Endocannabinoids
  • Enzyme Inhibitors
  • Glycerides
  • Sulfhydryl Compounds
  • glyceryl 2-arachidonate
  • Chloride Peroxidase
  • Monoacylglycerol Lipases
  • Cysteine