A bla(TEM-1b)-derived TEM-6 beta-lactamase: a case of convergent evolution
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چکیده
منابع مشابه
A bla(TEM-1b)-derived TEM-6 beta-lactamase: a case of convergent evolution.
Since the first communication describing an organism that produces an enzyme capable of hydrolyzing extended-spectrum cephalosporins (5, 6), several outbreaks of Enterobacte-riaceae resistant to oxyimino--lactams have been reported. In these cases, the adopted survival strategy of bacteria challenged by the introduction of aztreonam, cefotaxime, ceftazi-dime, and other oxyimino--lactams was t...
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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 repo...
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15 صفحه اولPredicting evolutionary potential: in vitro evolution accurately reproduces natural evolution of the tem beta-lactamase.
To evaluate the validity of our in vitro evolution method as a model for natural evolutionary processes, the TEM-1 beta-lactamase gene was evolved in vitro and was selected for increased resistance to cefotaxime, cefuroxime, ceftazadime, and aztreonam, i.e., the "extended-spectrum" phenotype. The amino acid substitutions recovered in 10 independent in vitro evolvants were compared with the amin...
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ژورنال
عنوان ژورنال: Antimicrobial Agents and Chemotherapy
سال: 1997
ISSN: 0066-4804,1098-6596
DOI: 10.1128/aac.41.5.1206