title: Comparison of the anion inhibition profiles of the β- and γ-carbonic anhydrases from the pathogenic bacterium Burkholderia pseudomallei.
abstract: We report the cloning, purification and characterization of BpsβCA, a β-class carbonic anhydrase (CA, EC 4.2.1.1) from the pathogenic bacterium Burkholderia pseudomallei, the etiological agent of melioidosis, and compare its activity and inhibition with those of the γ-CA from the same organism, BpsγCA, recently investigated by our groups. BpsβCA showed a significant catalytic activity for the physiologic, CO2hydration reaction, with the following kinetic parameters, kcatof 1.6×105s-1and kcat/Kmof 3.4×107M-1×s-1. The inhibition of BpsβCA with a group of anions and small molecules was also investigated. The best inhibitors were sulfamide, sulfamic acid and phenylarsonic acid, which showed KIs in the range of 83-92µM, whereas phenylboronic acid, fluoride, cyanide, azide, bisulfite, tetraborate, perrhenate, perruthenate, peroxydisulfate, perchlorate, tetrafluoroborate, fluorosulfonate and hexafluorophosphate showed KIs>100mM. Other inhibitors of this new enzyme were bicarbonate, trithiocarbonate, some complex inorganic anions and N,N-diethyldithiocarbamate, which had inhibition constants of 0.32-8.6mM. As little is known of the life cycle and virulence of this bacterium, this type of study may bring information of interest for the development of novel strategies to fight bacterial infection and drug resistance to commonly used antibiotics.
authors.affiliation: Istituto di Bioscienze e Biorisorse, CNR, Via Pietro Castellino 111, 80131 Napoli, Italy; Università degliStudi di Firenze, Dipartimento Di Chimica, Laboratorio di Chimica Bioinorganica, Polo Scientifico, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy.
authors.forename: Sonia
authors.initials: S
authors.lastname: Del Prete
authors.affiliation: Università degliStudi 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: Pietro
authors.initials: P
authors.lastname: di Fonzo
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: Università degliStudi di Firenze, Dipartimento Di Chimica, Laboratorio di Chimica Bioinorganica, Polo Scientifico, Via della Lastruccia 3, 50019 Sesto Fiorentino, Florence, Italy; Università degli Studi di Firenze, Dipartimento Neurofarba, Sezione di ScienzeFarmaceutiche 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; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016957:Burkholderia pseudomallei / Q000201:enzymology*; D002257:Carbonic Anhydrase Inhibitors / Q000494:pharmacology*; D002256:Carbonic Anhydrases / Q000737:chemistry; D002384:Catalysis; D007700:Kinetics; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid
chemical_list: D000900:Anti-Bacterial Agents; D002257:Carbonic Anhydrase Inhibitors; D002256:Carbonic Anhydrases
keywords: Anion; Burkholderia pseudomallei; Carbonic anhydrase; Inhibitor; Metalloenzymes; Pathogens; β-class