title: Characterization of a novel extended-spectrum TEM-type beta-lactamase, TEM-164, in a clinical strain of Klebsiella pneumoniae in Tunisia.
abstract: Klebsiella pneumoniae ML1708 exhibited a multiresistance phenotype, including resistance to all beta-lactams tested, chloramphenicol, ciprofloxacin, nalidixic acid, tetracycline, and streptomycin. The double-disk synergy test was positive. ML1708 harbored a 50 kb conjugative plasmid that encoded a beta-lactamase of pI 5.5. The corresponding bla gene was identified by polymerase chain reaction and sequencing as a bla(TEM) gene. The deduced protein sequence revealed a new variant of TEM-1 beta-lactamase designated TEM-164. TEM-164 contains the unusual following mutations: L40V and I279T. These modifications may result in a change of the pI to 5.5 and hydrolyze cefotaxime and ceftazidime.
authors.affiliation: Laboratory of Biochemistry and Biotechnology, Faculty of Sciences of Tunis, Campus Universitaire, Tunis, Tunisia. benachour_nahed@yahoo.fr
authors.forename: Nahed
authors.initials: N
authors.lastname: Ben Achour
authors.forename: Paola Sandra
authors.initials: PS
authors.lastname: Mercuri
authors.forename: Mohamed
authors.initials: M
authors.lastname: Ben Moussa
authors.forename: Moreno
authors.initials: M
authors.lastname: Galleni
authors.forename: Omrane
authors.initials: O
authors.lastname: Belhadj
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003227:Conjugation, Genetic; D024901:Drug Resistance, Multiple, Bacterial; D006801:Humans; D007710:Klebsiella Infections / Q000453:epidemiology* / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009154:Mutation; D017422:Sequence Analysis, DNA; D014416:Tunisia / Q000453:epidemiology; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000145:classification* / Q000235:genetics; D047090:beta-Lactams / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D001618:beta-Lactamases; C034413:beta-lactamase TEM-1