Anion inhibition profiles of α-, β- and γ-carbonic anhydrases from the pathogenic bacterium Vibrio cholerae.
Among the numerous metalloenzymes known to date, carbonic anhydrase (CA, EC 4.2.1.1) was the first zinc containing one, being discovered decades ago. CA is a hydro-lyase, which catalyzes the following hydration-dehydration reaction: CO2+H2O⇋HCO3(-)+H(+). Several CA classes are presently known, including the α-, β-, γ-, δ-, ζ- and η-CAs. In prokaryotes, the existence of genes encoding CAs from at least three classes (α-, β- and γ-class) suggests that these enzymes play a key role in the physiology of these organisms. In many bacteria CAs are essential for the life cycle of microbes and their inhibition leads to growth impairment or growth defects of the pathogen. CAs thus started to be investigated in detail in bacteria, fungi and protozoa with the aim to identify antiinfectives with a novel mechanism of action. Here, we investigated the catalytic activity, biochemical properties and anion inhibition profiles of the three CAs from the bacterial pathogen Vibrio cholera, VchCA, VchCAβ and VchCAγ. The three enzymes are efficient catalysts for CO2 hydration, with kcat values ranging between (3.4-8.23)×10(5)s(-1) and kcat/KM of (4.1-7.0)×10(7)M(-1)s(-1). A set of inorganic anions and small molecules was investigated for inhibition of these enzymes. The most potent VchCAγ inhibitors were N,N-diethyldithiocarbamate, sulfamate, sulfamide, phenylboronic acid and phenylarsonic acid, with KI values ranging between 44 and 91μM.
Istituto di Bioscienze e Biorisorse, CNR, Via Pietro Castellino 111, Napoli, Italy; Università degli Studi di Firenze, Dipartimento Di Chimica, Laboratorio di Chimica Bioinorganica, Polo Scientifico, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy.
Sonia
S
Del Prete
Università degli Studi di Firenze, Dipartimento Di Chimica, Laboratorio di Chimica Bioinorganica, Polo Scientifico, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy.
Daniela
D
Vullo
Istituto di Bioscienze e Biorisorse, CNR, Via Pietro Castellino 111, Napoli, Italy.
Viviana
V
De Luca
Istituto di Bioscienze e Biorisorse, CNR, Via Pietro Castellino 111, Napoli, Italy.
Vincenzo
V
Carginale
Istituto di Bioscienze e Biorisorse, CNR, Via Pietro Castellino 111, Napoli, Italy.
Pietro
P
di Fonzo
Department of Chemistry, College of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia.
Sameh M
SM
Osman
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.
Zeid
Z
AlOthman
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.
Claudiu T
CT
Supuran
Istituto di Bioscienze e Biorisorse, CNR, Via Pietro Castellino 111, Napoli, Italy. Electronic address: clemente.capasso@ibbr.cnr.it.
Clemente
C
Capasso
D002257:Carbonic Anhydrase Inhibitors / Q000494:pharmacology*; D002256:Carbonic Anhydrases / Q000378:metabolism*; D004795:Enzyme Stability; D006358:Hot Temperature; D006801:Humans; D007700:Kinetics; D014734:Vibrio cholerae / Q000201:enzymology*
D002257:Carbonic Anhydrase Inhibitors; D002256:Carbonic Anhydrases
Anions; Carbonic anhydrase; Hydratase activity; Inhibitors; Metalloenzymes; Pathogenic bacteria