title: Two novel plasmid-mediated cefotaxime-hydrolyzing beta-lactamases (CTX-M-5 and CTX-M-6) from Salmonella typhimurium.
abstract: Two novel plasmid-mediated beta-lactamases (CTX-M-5 and CTX-M-6) produced by Salmonella typhimurium clinical strains were characterized. The enzymes exhibited a pI of 8.4, hydrolyzed oxyimino-beta-lactams and were susceptible to mechanism-based beta-lactamase inhibitors. The respective bla genes were cloned and sequenced. The deduced amino acid sequences showed a high degree of homology with those of the previously described plasmid class A CTX-M-type enzymes and appeared related to the chromosomal beta-lactamases of Klebsiella oxytoca.
authors.affiliation: Department of Bacteriology, Hellenic Pasteur Institute, Athens, Greece.
authors.forename: M
authors.initials: M
authors.lastname: Gazouli
authors.forename: E
authors.initials: E
authors.lastname: Tzelepi
authors.forename: A
authors.initials: A
authors.lastname: Markogiannakis
authors.forename: N J
authors.initials: NJ
authors.lastname: Legakis
authors.forename: L S
authors.initials: LS
authors.lastname: Tzouvelekis
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001483:Base Sequence; D002439:Cefotaxime / Q000378:metabolism* / Q000494:pharmacology; D018550:Cephalosporin Resistance / Q000235:genetics; D002511:Cephalosporins / Q000378:metabolism* / Q000494:pharmacology; D005798:Genes, Bacterial; D006801:Humans; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics*; D012486:Salmonella typhimurium / Q000187:drug effects / Q000201:enzymology / Q000235:genetics*; D017422:Sequence Analysis, DNA; D001618:beta-Lactamases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; C114942:beta-lactamase CTX-M-5; C114943:beta-lactamase CTX-M-6; D001618:beta-Lactamases; D002439:Cefotaxime