Carbonic anhydrase inhibitors: interactions of phenols with the 12 catalytically active mammalian isoforms (CA I-XIV).
The inhibition of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1) with three phenols was investigated. Phenol was an effective CA I-IV, IX, XII and XIV inhibitor (K(I)s of 2.7-11.5 microM) and a less effective one against the other isoforms, CA VA, VB, VI, VII, and XIII (K(I)s of 208-710 micraoM). 3,5-Difluorophenol was an effective inhibitor of CA III, IV, IX, and XIV (K(I)s of 0.71-10.7 microM) being a weaker one for CA I, II, VA, VB, VI, VII, XII, and XIII (K(I)s of 33.9-163 microM). Clioquinol (5-chloro-7-iodo-8-quinolinol) was the best phenol inhibitor against all isozymes, with inhibition constants in the range of 3.3-16.0 microM. These data prove that the phenol OH moiety can be considered as a new 'zinc-water binding group' for the design of CA inhibitors possessing a different inhibition mechanism as compared to the classical sulfonamide inhibitors that bind the metal ion within the active site cavity.
Innocenti
Alessio
A
Università degli Studi di Firenze, Polo Scientifico, Laboratorio di Chimica Bioinorganica, Rm. 188, Via della Lastruccia 3, 50019 Sesto Fiorentino (Florence), Italy.
Vullo
Daniela
D
Scozzafava
Andrea
A
Supuran
Claudiu T
CT
D000818:Animals; D001665:Binding Sites; D002257:Carbonic Anhydrase Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D002256:Carbonic Anhydrases / Q000737:chemistry / Q000378:metabolism*; D008322:Mammals; D015394:Molecular Structure; D011485:Protein Binding; D020033:Protein Isoforms
D002257:Carbonic Anhydrase Inhibitors; D020033:Protein Isoforms; D002256:Carbonic Anhydrases