title: Comparison of the sulfonamide inhibition profiles of the α-, β- and γ-carbonic anhydrases from the pathogenic bacterium Vibrio cholerae.
abstract: Carbonic anhydrases (CA, EC 4.2.1.1) are ubiquitous metalloenzymes, which catalyze the conversion of carbon dioxide (CO2) to bicarbonate (HCO3(-)) and protons (H(+)). In prokaryotes, the existence of genes encoding for α-, β- and γ-classes suggests that these enzymes play an important role in the prokaryotic physiology. It has been demonstrated, in fact, that their inhibition in vivo leads to growth impairment or growth defects of the microorganism. Ultimately, we started to investigate the biochemical properties and the inhibitory profiles of the α- and β-CAs identified in the genome of Vibrio cholerae, which is the causative agent of cholera. The genome of this pathogen encodes for CAs belonging to α, β and γ classes. Here, we report a sulfonamide inhibition study of the γ-CA (named VchCAγ) comparing it with data obtained for the α- and β-CA enzymes. VchCAγ activity (kcat=7.39 × 10(5)s(-1)) was significantly higher than the other γ-CAs. The inhibition study with a panel of sulfonamides and one sulfamate led to the detection of a large number of nanomolar VchCAγ inhibitors, including simple aromatic/heterocyclic sulfonamides (compounds 2-9, 11, 13-15, 24) as well as EZA, DZA, BRZ, BZA, TPM, ZNS, SLP, IND (KIs in the range of 66.2-95.3 nM). As it was proven that bicarbonate is a virulence factor of this bacterium and since ethoxzolamide was shown to inhibit this virulence in vivo, we propose that VchCA, VchCAβ and VchCAγ may be a target for antibiotic development, exploiting a mechanism of action rarely considered up until now, i.e., interference with bicarbonate supply as a virulence factor.
authors.affiliation: Università degli Studi di Firenze, Dipartimento Di Chimica, Laboratorio di Chimica Bioinorganica, Polo Scientifico, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy; Istituto di Bioscienze e Biorisorse, CNR, Via Pietro Castellino 111, 80131, Napoli, Italy.
authors.forename: Sonia
authors.initials: S
authors.lastname: Del Prete
authors.affiliation: Università degli Studi di Firenze, Dipartimento Di Chimica, Laboratorio di Chimica Bioinorganica, Polo Scientifico, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Vullo
authors.affiliation: Istituto di Bioscienze e Biorisorse, CNR, Via Pietro Castellino 111, 80131, Napoli, Italy.
authors.forename: Viviana
authors.initials: V
authors.lastname: De Luca
authors.affiliation: Istituto di Bioscienze e Biorisorse, CNR, Via Pietro Castellino 111, 80131, Napoli, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Carginale
authors.affiliation: Department of Chemistry, College of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia; Advanced Materials Research Chair, Chemistry Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
authors.forename: Sameh M
authors.initials: SM
authors.lastname: Osman
authors.affiliation: Department of Chemistry, College of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia; Advanced Materials Research Chair, Chemistry Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
authors.forename: Zeid
authors.initials: Z
authors.lastname: AlOthman
authors.affiliation: Department of Chemistry, College of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia; Università degli Studi di Firenze, Dipartimento Neurofarba, Sezione di Scienze Farmaceutiche e Nutraceutiche, Via U. Schiff 6, 50019 Sesto Fiorentino, Florence, Italy. Electronic address: claudiu.supuran@unifi.it.
authors.forename: Claudiu T
authors.initials: CT
authors.lastname: Supuran
authors.affiliation: Istituto di Bioscienze e Biorisorse, CNR, Via Pietro Castellino 111, 80131, Napoli, Italy. Electronic address: clemente.capasso@ibbr.cnr.it.
authors.forename: Clemente
authors.initials: C
authors.lastname: Capasso
mesh_terms: D000595:Amino Acid Sequence; D002257:Carbonic Anhydrase Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D002256:Carbonic Anhydrases / Q000235:genetics / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D015394:Molecular Structure; D013329:Structure-Activity Relationship; D013449:Sulfonamides / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D014734:Vibrio cholerae / Q000201:enzymology* / Q000235:genetics
chemical_list: D002257:Carbonic Anhydrase Inhibitors; D013449:Sulfonamides; D002256:Carbonic Anhydrases
keywords: Carbonic anhydrase; Hydratase activity; Inhibitors; Metalloenzymes; Oligomeric state; Protonography; Sulfonamide