Anion inhibition studies of a β-carbonic anhydrase from Clostridium perfringens

Bioorg Med Chem Lett. 2013 Dec 15;23(24):6706-10. doi: 10.1016/j.bmcl.2013.10.037. Epub 2013 Oct 29.


A β-carbonic anhydrases (CAs, EC was recently cloned, purified and characterized kinetically in the pathogen Clostridium perfringens. We report here the first inhibition study of this enzyme (CpeCA). CpeCA was poorly inhibited by iodide and bromide, and was inhibited with KIs in the range of 1-10mM by a range of anions such as (thio)cyanate, azide, bicarbonate, nitrate, nitrite, hydrogensulfite, hydrogensulfide, stannate, tellurate, pyrophosphate, divanadate, tetraborate, peroxydisulfate, sulfate, iminodisulfonate and fluorosulfonate. Better inhibitory power, with K(I)s of 0.36-1.0 mM, was observed for cyanide, carbonate, selenate, selenocyanide, trithiocarbonate and diethyldithiocarbamate, whereas the best CpeCA inhibitors were sulfamate, sulfamide, phenylboronic acid and phenylarsonic acid, which had KIs in the range of 7-75 μM. This study thus provides the basis for developing better clostridial enzyme inhibitors with potential as antiinfectives with a new mechanism of action.

Keywords: Anion; Beta class enzyme; Carbonic anhydrase; Clostridium perfringens; Sulfonamide.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Anions / chemistry*
  • Anions / metabolism
  • Anions / pharmacology*
  • Bacterial Proteins / antagonists & inhibitors*
  • Bacterial Proteins / metabolism
  • Carbonic Anhydrase Inhibitors / chemistry*
  • Carbonic Anhydrase Inhibitors / metabolism
  • Carbonic Anhydrase Inhibitors / pharmacology*
  • Carbonic Anhydrases / chemistry*
  • Carbonic Anhydrases / metabolism
  • Clostridium perfringens / classification
  • Clostridium perfringens / enzymology*
  • Enzyme Activation / drug effects
  • Humans
  • Kinetics
  • Molecular Sequence Data
  • Phylogeny
  • Protein Binding / drug effects
  • Sequence Alignment


  • Anions
  • Bacterial Proteins
  • Carbonic Anhydrase Inhibitors
  • Carbonic Anhydrases