Ceftazidime and aztreonam resistance in Providencia stuartii: characterization of a natural TEM-derived extended-spectrum beta-lactamase, TEM-60.
نویسندگان
چکیده
A plasmid-encoded beta-lactamase produced from a clinical strain of Providencia stuartii has been purified and characterized. The gene coding for the beta-lactamase was cloned and sequenced. It appears to be a new natural TEM-derived enzyme, named TEM-60. Point mutations (Q39K, L51P, E104K, and R164S) are present with respect to the TEM-1 enzyme; the mutation L51P has never been previously reported, with the exception of the chromosomally encoded extended-spectrum beta-lactamase PER-1. Kinetic parameters relative to penicillins, cephalosporins, and monobactams other than mechanism-based inactivators were related to the in vitro susceptibility phenotype.
منابع مشابه
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ورودعنوان ژورنال:
- Antimicrobial agents and chemotherapy
دوره 42 6 شماره
صفحات -
تاریخ انتشار 1998