OBJECTIVES To characterize a novel ceftazidime-hydrolysing CTX-M mutant, designated CTX-M-54, produced by Klebsiella pneumoniae clinical isolate BDK0419 and to investigate its genetic environment. METHODS Antimicrobial susceptibilities were determined by disc diffusion and agar dilution methods, and the double-disc synergy test was carried out. Detection of genes encoding class A beta-lactama...

5 Abstract Aim: To analyse the occurrence of bla genes (blaIMP, blaVIM, blaGIM, blaSIM, blaSPM, blaPER, blaKPC, and blaOXA) responsible for carbapenemresistance, as well as the presence of cephalosporin-resistance genes (blaCTX-M, blaTEM, blaSHV and blaampC ) by polymerase chain reactions (PCRs). Methods: The study was performed on routine samples subjected to culture and antibiotics susceptibi...

Within the ESBL family the most common genes are temoneira (blaTEM) and sulfhydryl variable (blaSHV) with increasing reports of cefotaximase (blaCTX-M) [4]. The blaSHV and the blaTEM subgroups arise from mutational changes due to point mutations in the genes resulting in subtypes. Examples include blaSHV which differs from blaSHV-1 due to a single mutation of an amino acid from glycine to serin...

CTX-M extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae isolates are infrequently reported in the United States. In this study, we analyzed nonduplicate ESBL-producing K. pneumoniae and Escherichia coli clinical isolates collected during 2005-2012 at a tertiary care medical center in suburban New York City, USA, for the presence of blaCTX-M, blaSHV, blaTEM, and blaKPC genes. ...

To characterize the extended-spectrum beta-lactamases (ESBLs) in diarrheagenic Escherichia coli from Korea in 2008-2011, we screened seven enterotoxigenic E. coli (ETEC) and one enteroaggregative E. coli (EAEC) that produce ESBLs from a nationwide survey. All eight isolates produced CTX-M-type ESBLs, including CTX-M-12 (n = 4), CTX-M-14 (n = 2), and CTX-M-15 (n = 2). PCR-based replicon typing i...

The present work reports the study of the antimicrobial activity of four quinoxaline N,N-dioxide: quinoxaline 1,4-dioxide, 2-methylquinoxaline 1,4-dioxide, 6chloro-2,3-dimethylquinoxaline 1,4-dioxide and 3-benzoyl-2-methylquinoxaline 1,4dioxide against Geobacillus stearothermophilus ATCC 10149, Escherichia coli ATCC 25922, Escherichia coli HB101, Escherichia coli (blaTEM, blaCTX-M) and Salmonel...

OBJECTIVES We characterized plasmids encoding CTX-M-14 β-lactamase originating from Escherichia coli isolates recovered from patients with uncomplicated cystitis or individuals with faecal colonization in Hong Kong from 2002 to 2004. METHODS Plasmids carrying CTX-M-14 were studied by conjugation, replicon typing, S1 nuclease-PFGE and plasmid PCR-restriction fragment length polymorphism (RFLP)...