Cloning, Characterization, and Sulfonamide and Thiol Inhibition Studies of an α-carbonic Anhydrase From Trypanosoma Cruzi, the Causative Agent of Chagas Disease

J Med Chem. 2013 Feb 28;56(4):1761-71. doi: 10.1021/jm4000616. Epub 2013 Feb 19.

Abstract

An α-carbonic anhydrase (CA, EC 4.2.1.1) has been identified, cloned, and characterized from the unicellular protozoan Trypanosoma cruzi, the causative agent of Chagas disease. The enzyme (TcCA) has a very high catalytic activity for the CO2 hydration reaction, being similar kinetically to the human (h) isoform hCA II, although it is devoid of the His64 proton shuttle. A large number of aromatic/heterocyclic sulfonamides and some 5-mercapto-1,3,4-thiadiazoles were investigated as TcCA inhibitors. The aromatic sulfonamides were weak inhibitors (K(I) values of 192 nM to 84 μM), whereas some heterocyclic compounds inhibited the enzyme with K(I) values in the range 61.6-93.6 nM. The thiols were the most potent in vitro inhibitors (K(I) values of 21.1-79.0 nM), and some of them also inhibited the epimastigotes growth of two T. cruzi strains in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Carbonic Anhydrase Inhibitors / chemical synthesis
  • Carbonic Anhydrase Inhibitors / chemistry*
  • Carbonic Anhydrase Inhibitors / pharmacology
  • Carbonic Anhydrases / chemistry
  • Carbonic Anhydrases / genetics*
  • Chagas Disease / parasitology
  • Cloning, Molecular
  • Humans
  • Molecular Sequence Data
  • Phylogeny
  • Protozoan Proteins / antagonists & inhibitors
  • Protozoan Proteins / chemistry
  • Protozoan Proteins / genetics*
  • Structure-Activity Relationship
  • Sulfhydryl Compounds / chemical synthesis
  • Sulfhydryl Compounds / chemistry*
  • Sulfhydryl Compounds / pharmacology
  • Sulfonamides / chemical synthesis
  • Sulfonamides / chemistry*
  • Sulfonamides / pharmacology
  • Thiadiazoles / chemical synthesis
  • Thiadiazoles / chemistry*
  • Thiadiazoles / pharmacology
  • Trypanocidal Agents / chemical synthesis
  • Trypanocidal Agents / chemistry*
  • Trypanocidal Agents / pharmacology
  • Trypanosoma cruzi / drug effects
  • Trypanosoma cruzi / enzymology*

Substances

  • Carbonic Anhydrase Inhibitors
  • Protozoan Proteins
  • Sulfhydryl Compounds
  • Sulfonamides
  • Thiadiazoles
  • Trypanocidal Agents
  • Carbonic Anhydrases