0022-2836/$ see front matter © 2009 E β-Lactamase inhibitory protein (BLIP) binds and inhibits a diverse collection of class A β-lactamases with a wide range of affinities. Alaninescanning mutagenesis was previously performed to identify the amino acid sequence requirements of BLIP for binding the TEM-1, SME-1, SHV-1, and Bla1 β-lactamases. Twenty-three BLIP residues that contact TEM-1 βlactama...

A total of 47 extended-spectrum-cephalosporin-resistant Escherichia coli strains isolated from stray dogs in 2006 and 2007 in the Republic of Korea were investigated using molecular methods. Extended-spectrum β-lactamase (ESBL) and AmpC β-lactamase phenotypes were identified in 12 and 23 E. coli isolates, respectively. All 12 ESBL-producing isolates carried bla(CTX-M) genes. The most common CTX...

OBJECTIVES A relapse from Escherichia coli bloodstream infection was observed in a patient with acute leukaemia treated with ceftazidime for 7 days for febrile neutropenia. Whereas the original E. coli isolate was resistant to β-lactam/β-lactamase inhibitor combinations (EC1), the relapse E. coli isolate showed a similar phenotype but with resistance extended to ceftazidime (EC2). We investigat...

BACKGROUND Gastroenteritis attributable to Salmonella enterica and the continuous increase in antimicrobial resistance of this gut pathogen, which compromises the use of previously effective treatments, is of great concern for public health. This study was conducted in order to investigate the presence of plasmid-mediated quinolone resistance (PMQR) determinants and β-lactamase-encoding genes, ...

The treatment ofStenotrophomonas maltophiliainfection with β-lactam antibiotics leads to increased release of outer membrane vesicles (OMVs), which are packed with two chromosomally encoded β-lactamases. Here, we show that these β-lactamase-packed OMVs are capable of establishing extracellular β-lactam degradation. We also show that they dramatically increase the apparent MICs of imipenem and t...

background and objectives: β-lactamase production is the predominant mechanism for resistance to β-lactams in enterobacteriaceae. the producing isolates are often multidrug resistant and are major hosts for extended spectrum β-lactamases. this study was designed to determine the prevalence of extended-spectrum β-lactamase producing isolates of escherichia coli and klebsiella pneumoniae and thei...