Cloning of SHV-2, OHIO-1, and OXA-6 beta-lactamases and cloning and sequencing of SHV-1 beta-lactamase

Diversity of SHV and TEM beta-lactamases in Klebsiella pneumoniae: gene evolution in Northern Taiwan and two novel beta-lactamases, SHV-25 and SHV-26.

A total of 113 blood culture isolates of Klebsiella pneumoniae from 10 hospitals in northern Taiwan were studied for SHV and TEM beta-lactamase production. bla(SHV) was amplified from all isolates by PCR. TEM-type resistance, was found in 32 of the isolates and was of the TEM-1 type in all isolates. SHV-1, -2, -5, -11, and -12 and two novel enzymes were identified. These novel enzymes were desi...

Survey and molecular genetics of SHV beta-lactamases in Enterobacteriaceae in Switzerland: two novel enzymes, SHV-11 and SHV-12.

Sixty isolates of Enterobacteriaceae resistant to beta-lactam antibiotics were collected over a period of 2 years in Switzerland and screened by hybridization for the carriage of SHV genes. Thirty-four positive strains were found, and their SHV genes were amplified and sequenced. SHV extended-spectrum beta-lactamases (ESBLs) were found: 13 strains contained SHV-2a, 12 harbored SHV-2, and SHV-5 ...

Avibactam and inhibitor resistant SHV β - lactamases 1 2

Kinetic 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...

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, ...