Emergence of an inhibitor-resistant beta-lactamase (SHV-10) derived from an SHV-5 variant
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Emergence of an inhibitor-resistant beta-lactamase (SHV-10) derived from an SHV-5 variant.
An inhibitor-resistant beta-lactamase (SHV-10), derived from an SHV-5 variant (SHV-9), was found in an Escherichia coli clinical isolate. In SHV-10, Ser-130 was replaced by Gly. The enzyme partially retained its ability to hydrolyze penicillins, but its activity against cephalosporins was drastically reduced. A Ser-130-->Gly mutant of the prototype SHV-5, obtained by site-directed mutagenesis, ...
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We biochemically characterized the Klebsiella pneumoniae extended-spectrum SHV-55 enzyme carrying the amino acid substitutions Tyr73Phe (as in SHV-28) and Gly2383Ser and Glu2403Lys (both found in SHV-5) identified in a previous study (5). The SHV-55 extended-spectrum -lactamase differed from SHV-5 only in the signal peptide region (1). The blaSHV-55 gene was obtained as described by Mendonça et...
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ژورنال
عنوان ژورنال: Antimicrobial Agents and Chemotherapy
سال: 1997
ISSN: 0066-4804,1098-6596
DOI: 10.1128/aac.41.4.838