title: Purification and characterization of beta-lactamase from Neisseria gonorrhoeae from clinical samples.
abstract: beta-Lactamase was isolated from Neisseria gonorrhoeae, obtained from male patients with gonococcic urethritis. Biochemical properties of the enzyme were studied. The enzyme was purified 38-fold by ammonium sulphate precipitation and using Sephadex G75 and DEAE-cellulose columns. The purified extract exhibited a single band by polyacrylamide gel electrophoresis. Maximum enzyme activity was obtained at 37 degrees C and pH 7.0-7.2 in 50 mM phosphate buffer. Addition of Ni2+, Fe2+, Fe3+, Mn2+ and p-chloromercurybenzoate to the reaction buffer partially inhibited beta-lactamase activity, whereas Hg2+ and EDTA produced complete inhibition. The molecular weight was estimated to be 35,000 Da and the pI of the enzyme was 5.4.
authors.affiliation: Instituto de Microbiología, Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Argentina. microbiologia.clinica@unt.edu.ar
authors.forename: M C
authors.initials: MC
authors.lastname: de Castillo
authors.forename: M I
authors.initials: MI
authors.lastname: Islas
authors.forename: O M
authors.initials: OM
authors.lastname: de Nader
authors.forename: A P
authors.initials: AP
authors.lastname: de Ruiz-Holgado
mesh_terms: D001426:Bacterial Proteins / Q000037:antagonists & inhibitors / Q000302:isolation & purification* / Q000378:metabolism; D002412:Cations / Q000494:pharmacology; D006069:Gonorrhea / Q000382:microbiology*; D006358:Hot Temperature; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007526:Isoelectric Point; D008297:Male; D008970:Molecular Weight; D009344:Neisseria gonorrhoeae / Q000201:enzymology*; D011489:Protein Denaturation; D013379:Substrate Specificity; D013696:Temperature; D014526:Urethritis / Q000382:microbiology*; D065093:beta-Lactamase Inhibitors; D001618:beta-Lactamases / Q000302:isolation & purification* / Q000378:metabolism; D020245:p-Chloromercuribenzoic Acid / Q000494:pharmacology
chemical_list: D001426:Bacterial Proteins; D002412:Cations; D065093:beta-Lactamase Inhibitors; D020245:p-Chloromercuribenzoic Acid; D001618:beta-Lactamases