Characterization of a novel SHV β-lactamase variant that resembles the SHV-5 enzyme
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چکیده
منابع مشابه
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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The clinical Klebsiella pneumoniae INSRA6884 strain exhibited nonsusceptibility to all penicillins tested (MICs of 64 to >2,048 μg/ml). The MICs of penicillins were weakly reduced by clavulanate (from 2,048 to 512 μg/ml), and tazobactam restored piperacillin susceptibility. Molecular characterization identified the genes bla(GES-7) and a new β-lactamase gene, bla(SHV-107), which encoded an enzy...
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Klebsiella pneumoniae ML2011, a multiresistant isolate, was isolated from the Military Hospital of Tunis (Tunisia). The determination of the minimal inhibitory concentrations exhibited by K. pneumoniae ML2011 was performed by Etest. The crude extract of the isolates contains four different β -lactamases with pI 5.5, 7.3, 7.6, and 8.6. Only the β -lactamases with pI 7.3 and pI 8.6 were transferr...
متن کاملMolecular and biochemical characterization of SHV-56, a novel inhibitor-resistant beta-lactamase from Klebsiella pneumoniae.
A clinical strain of Klebsiella pneumoniae was found to possess the chromosomal gene bla(SHV-56), encoding a new inhibitor-resistant beta-lactamase with a pI of 7.6. SHV-56 is derived from SHV-11 by the single substitution K234R. This mutation therefore evidences a new critical site for inhibitor resistance among SHV enzymes.
متن کاملKinetic analysis of an inhibitor-resistant variant of the OHIO-1 beta-lactamase, an SHV-family class A enzyme.
The Met69-->Ile mutant of the OHIO-1 beta-lactamase, an SHV-family enzyme, is resistant to inactivation by beta-lactamase inhibitors. Analysis of purified Met69-->Ile enzyme reveals that its isoelectric point (pI 7.0) and CD spectrum are identical with those of the OHIO-1 enzyme. Levels of beta-lactamase expression in Escherichia coli as determined by immunoblotting are similar for OHIO-1 and M...
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ژورنال
عنوان ژورنال: FEMS Microbiology Letters
سال: 1996
ISSN: 0378-1097,1574-6968
DOI: 10.1111/j.1574-6968.1996.tb08207.x