Anion inhibition studies of two new β-carbonic anhydrases from the bacterial pathogen Legionella pneumophila.
We investigated the cloning, catalytic activity and anion inhibition of the β-class carbonic anhydrases (CAs, EC 4.2.1.1) from the bacterial pathogen Legionella pneumophila. Two such enzymes, lpCA1 and lpCA2, were found in the genome of this pathogen. These enzymes were determined to be efficient catalysts for CO2 hydration, with kcat values in the range of (3.4-8.3)×10(5) s(-1) and kcat/KM values of (4.7-8.5)×10(7) M(-1) s(-1). A set of inorganic anions and small molecules was investigated to identify inhibitors of these enzymes. Perchlorate and tetrafluoroborate were not acting as inhibitors (KI >200 mM), whereas sulfate was a very weak inhibitor for both lpCA1 and lpCA2 (KI values of 77.9-96.5 mM). The most potent lpCA1 inhibitors were cyanide, azide, hydrogen sulfide, diethyldithiocarbamate, sulfamate, sulfamide, phenylboronic acid and phenylarsonic acid, with KI values ranging from 6 to 94 μM. The most potent lpCA2 inhibitors were diethyldithiocarbamate, sulfamide, sulfamate, phenylboronic acid and phenylarsonic acid, with KI values ranging from 2 to 13 μM. As these enzymes seem to be involved in regulation of phagosome pH during Legionella infection, inhibition of these targets may lead to antibacterial agents with a novel mechanism of action.
Department of Gastroenterology, Kochi Medical School, Kochi, Japan.
Isao
I
Nishimori
Università degli Studi di Firenze, Polo Scientifico, Laboratorio di Chimica Bioinorganica, Rm. 188, Via della Lastruccia 3, 50019 Sesto Fiorentino (Florence), Italy.
Daniela
D
Vullo
Department of Gastroenterology, Kochi Medical School, Kochi, Japan.
Tomoko
T
Minakuchi
Università degli Studi di Firenze, Polo Scientifico, Laboratorio di Chimica Bioinorganica, Rm. 188, Via della Lastruccia 3, 50019 Sesto Fiorentino (Florence), Italy.
Andrea
A
Scozzafava
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.
Zeid
Z
AlOthman
Istituto di Biochimica delle Proteine-CNR, Via P. Castellino 111, 80131 Napoli, Italy.
Clemente
C
Capasso
Università degli Studi di Firenze, Polo Scientifico, Laboratorio di Chimica Bioinorganica, Rm. 188, Via della Lastruccia 3, 50019 Sesto Fiorentino (Florence), Italy; Department of Chemistry, College of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia; Università degli Studi di Firenze, Polo Scientifico, Dipartimento di Scienze Farmaceutiche, Via Ugo Schiff 6, 50019 Sesto Fiorentino (Florence), Italy. Electronic address: claudiu.supuran@unifi.it.
Claudiu T
CT
Supuran
D000838:Anions / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D002256:Carbonic Anhydrases / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D016952:Legionella pneumophila / Q000201:enzymology*; D008968:Molecular Conformation; D013329:Structure-Activity Relationship
D000838:Anions; D004791:Enzyme Inhibitors; D002256:Carbonic Anhydrases
Anion; Carbonic anhydrase; Dithiocarbamate; Legionella pneumophila; Sulfamide; β-Class enzyme