title: CTX-M-type beta-lactamases: an emerging group of extended-spectrum enzymes.
abstract: CTX-M-type beta-lactamases constitute a novel group of class A beta-lactamases with extended-spectrum properties. They are encoded by transferable plasmids and found in various enterobacteria, mostly Salmonella typhimurium, Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis. CTX-M enzymes share extensive sequence similarity with the chromosomal beta-lactamases of Klebsiella oxytoca. They efficiently hydrolyze many newer broad-spectrum oximino-beta-lactams including cefotaxime, ceftriaxone and aztreonam and are readily inhibited by tazobactam and clavulanate. CTX-M-producing enterobacteria are endemic in Latin America and in some areas of North Eastern Europe. Data on their structure, properties and epidemiology are discussed.
authors.affiliation: Department of Microbiology, Medical School, National University of Athens, M. Asias 75, Athens, Greece.
authors.forename: L S
authors.initials: LS
authors.lastname: Tzouvelekis
authors.forename: E
authors.initials: E
authors.lastname: Tzelepi
authors.forename: P T
authors.initials: PT
authors.lastname: Tassios
authors.forename: N J
authors.initials: NJ
authors.lastname: Legakis
mesh_terms: D000595:Amino Acid Sequence; D001424:Bacterial Infections / Q000201:enzymology / Q000453:epidemiology / Q000382:microbiology; D004352:Drug Resistance, Microbial; D006801:Humans; D011487:Protein Conformation; D001618:beta-Lactamases / Q000737:chemistry / Q000378:metabolism*
chemical_list: D001618:beta-Lactamases