Five strains of cefotaxime-resistant (≤ 128 μg/ml) Escherichia coli were isolated from hospitals in Nagasaki Prefecture. These E. coli strains showed resistance against 3rd generation cephems and aztreonam (64μg/ml), but these strains were sensitive against imipenem. The antibiotic activity of piperacillin alone to these E. coli strains were > 128 μg/ml, in contrast, MIC values of piperacillin combined with tazobactam as a β-lactamase inhibitor were 4-32 μg/ml. These resistance were carried by a conjugative plasmid encoding for β-lactamases. These results suggested that 5 strains of E. coli were shown resistance against β-lactams by producing class A β- lactamase.
|Number of pages||5|
|Publication status||Published - 1997|
- Cefotaxamine-hydrolizing β-lactamase
- Cefoxamine-resistant Escherichia coli
- Extended-spectrum ̄- lactamase
ASJC Scopus subject areas