Pseudomonas aeruginosa is one of the most important causes of nosocomial infection and it has increasing resistance to many antimicrobial agents. β-lactamase production is the most frequent mechanism for β-lactam resistance in P. aeruginosa. We evaluated the prevalence of β-lactamase genes in P. aeruginosa for classes A, C, and D by polymerase chain reaction, and investigated clonal diversity b...

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...

A clinical isolate of Pseudomonas aeruginosa, PAe191, was found to be highly resistant to all anti-Pseudomonas beta-lactam antibiotics (except imipenem) and resistant also to aminoglycosides. It produced a beta-lactamase (with an apparent pI of 7.6) which was not inhibited by clavulanic acid. Cloning and characterization of the beta-lactamase gene showed that it coded for a novel extended-spect...

Two clonally related Pseudomonas aeruginosa isolates, recovered from two patients admitted to a pediatric intensive care unit, were found to harbor a new OXA-2 variant (Asn148Asp), designated OXA-161. The plasmid location of bla(OXA-161) was demonstrated through electroporation to PAO1, and its codification in a class I integron (together with aacA4) was demonstrated through PCR and sequencing....

We report the first multidrug-resistant Proteus mirabilis strain producing the carbapenemase OXA-48 (Pm-OXA-48) isolated at Al-Shifa hospital in Gaza, Palestine. Draft genome sequencing of Pm-OXA-48 identified 16 antimicrobial resistance genes, encoding resistance to β-lactams, aminoglycosides, fluoroquinolones, phenicols, streptothricin, tetracycline, and trimethoprim-sulfamethoxazole. Complet...

conclusions this study was the first report of the emergence of the plasmid-encoded blaoxa genes among e. cloacae isolates in iran. these findings highlight the need to use appropriate infection control policy and rational antibiotic therapy to reduce further spread of these resistant bacteria in the studied hospitals. results in total, 48 esbl-producing isolates (58.5%) were positive for the b...

OBJECTIVES Acinetobacter baumannii is a significant pathogen in health care settings. In recent years, an increase in carbapenem resistance among A. baumannii due to Ambler class B metallo-beta-lactamases or class D OXA carbapenamases has been reported. In this study we detected the presence of OXA carbapenamases and coproduction of metallo-beta-lactamases (blaVIM and blaIMP ) by phenotypic and...

The carbapenem-hydrolyzing class D β-lactamase OXA-253 was identified in an Acinetobacter baumannii clinical isolate belonging to sequence type 113 (ST113) in Brazil. OXA-253 shares 93.8% amino acid identity with OXA-143. The blaOXA-253 gene is located on a ca. 20-kb plasmid. The genetic environment of the blaOXA-253 gene shares the highest identity with ubiquitous GR2 group plasmids usually ca...

BACKGROUND/PURPOSE To investigate the characterization of bla(OxA-23) gene regions in isolates of Acinetobacter baumannii from Taizhou Municipal Hospital. METHODS Fifty-nine non-repetitive, multiresistant (including imipenem-resistant) isolates of A. baumannii were recovered from clinical infections in hospitalized patients from January 2010 to August 2011 in Taizhou Municipal Hospital (affil...

OBJECTIVES Recently, resistance to extended-spectrum cephalosporins due to acquired beta-lactamases has been reported in Pseudomonas aeruginosa. The aim of this study was to investigate the prevalence of Ambler class A and D beta-lactamases and their extended-spectrum derivatives and antimicrobial susceptibilities of P. aeruginosa isolated from various parts of Korea. METHODS A total of 252 c...