Carbepenems are used with increasing frequency to treat multidrug-resistant isolates, especially strains producing extended-spectrum β-lactamases [1, 2]. Resistance to carbapenems has been uncommon among Enterobacteriaceae. However, the emergence of β-lactamases with direct carbapenem-hydrolyzing activity has contributed to an increased prevalence of carbapenem-resistant Enterobacteriaceae (CRE...

Abstract Background Carbapenem resistance is a major concern of the World Health Organization (WHO) and Centers for Disease Control (CDC). The mortality in carbapenem-resistant infection ranges from 26-44%. Delays appropriate antibiotic therapy can lead to increased longer hospital stay. Studies have identified several risk factors associated with carbapenem including mechanical ventilation, in...

beta-Lactam synthetase (beta-LS) is the paradigm of a growing class of enzymes that form the critical beta-lactam ring in the clavam and carbapenem antibiotics. beta-LS catalyzes a two-stage reaction in which N(2)-(2-carboxyethyl)-L-arginine is first adenylated, and then undergoes intramolecular ring closure. It was previously shown that the forward kinetic commitment to beta-lactam formation i...

Knowledge regarding the genomic structure of Enterobacter spp., the second most prevalent carbapenemase-producing Enterobacteriaceae, remains limited. Here we sequenced 97 clinical Enterobacter species isolates that were both carbapenem susceptible and resistant from various geographic regions to decipher the molecular origins of carbapenem resistance and to understand the changing phylogeny of...

Carbapenem resistance in Escherichia coli is rare. We report four genetically unrelated carbapenem-resistant E. coli isolates cultured from four patients hospitalized in Tel Aviv Medical Center. PCR, sequencing, and Southern blot analysis identified KPC-2 as the imipenem-hydrolyzing enzyme in all four strains, carried on different plasmids with a possible common origin. This is the first discov...

Antimicrobial resistance in bacteria is problematic in clinical settings and is a growing threat to public health. Multidrug-resistant and pandrug-resistant non-fermenters such as Acinetobacter spp. and Pseudomonas aeruginosa have recently emerged as a great concern worldwide. Particularly, the prevalence of carbapenem resistance in Acinetobacter spp. and P. aeruginosa is problematic, and emerg...

The first outbreak of carbapenem-resistant Klebsiella pneumoniae isolates producing the plasmid-encoded carbapenem-hydrolyzing oxacillinase OXA-48 is reported. The 39 isolates belonged to two different clones and were collected at the University Hospital of Istanbul, Turkey, from May 2006 to February 2007, and they coproduced various beta-lactamases (SHV-12, OXA-9, and TEM-1 for clone A and CTX...

Plasmid-mediated carbapenem-hydrolyzing β-lactamases are becoming emerging threats with Enterobacteriaceae. In particular, the carbapenem-hydrolyzing class D β-lactamase OXA-48 and its derivative OXA-181 have been reported increasingly worldwide. Using a PCR-based strategy, environmental samples were screened for bla(OXA-48)-like genes. Shewanella xiamenensis, an environmental species from mari...

The genetic similarity of carbapenem-resistant Pseudomonas aeruginosa strains isolated in the Hospital Universitário São Francisco, Bragança Paulista, São Paulo, Brasil, was evaluated by pulsed field gel electrophoresis (PFGE). A unique clone was detected among 5 of 7 isolates, suggesting that cross-contamination might have played a role in the spread of carbapenem-resistant P. aeruginosa strai...

BACKGROUND Multidrug resistant Pseudomonas aeruginosa and Acinetobacter baumannii are common causes of health care associated infections worldwide. Carbapenems are effective against infections caused by multidrug resistant Gram-negative bacteria including Pseudomonas and Acinetobacter species. However, their use is threatened by the emergence of carbapenemase-producing strains. The aim of this ...