OBJECTIVE The present study was undertaken to characterize CTX-M ESBL-producing Klebsiella pneumoniae collected from hospitals in different cities of Brazil. MATERIAL AND METHODS Eighty-five K. pneumoniae strains isolated from hospitalized patients in six different hospitals of three cities of Brazil were analyzed. ESBL production was confirmed by the standard double-disk synergy test and the...

CTX-M β-lactamases are considered a paradigm in the evolution of a resistance mechanism. Incorporation of different chromosomal bla(CTX-M) related genes from different species of Kluyvera has derived in different CTX-M clusters. In silico analyses have shown that this event has occurred at least nine times; in CTX-M-1 cluster (3), CTX-M-2 and CTX-M-9 clusters (2 each), and CTX-M-8 and CTX-M-25 ...

OBJECTIVES To assess the frequency and diversity of extended spectrum beta-lactamases (ESBLs) in the Champagne-Ardenne region France, and to identify genetic elements associated with the bla(CTX-M) genes. METHODS During 2004, all the non-duplicate isolates of Pseudomonas aeruginosa and Acinetobacter baumannii resistant to ceftazidime and of Enterobacteriaceae intermediate or resistant to ceft...

Complete sequencing of pJIE137 revealed a backbone closely related to p271A, encoding a novel RepA protein but with a similar organization and up to ∼70% nucleotide identity to IncN plasmids. A region in pJIE137 resembling the IncN CUP regulon is mostly missing from p271A, presumably due to recombination. The class 1 In/Tn and ISEcp1-bla(CTX-M-62) transposition unit in pJIE137 and a putative tr...

Extended-spectrum β-lactamases (ESBL) producing bacteria have been increasingly reported in both hospital and community patients. Production of ESBLs is the major mechanism of resistance to oxymino-cephalosporins and aztreonam in Gram-negative bacteria. Recently a new family of ESBLs with predominant activity against cefotaxime (CTX-M β-lactamases) has been reported. Over 80 CTX-M enzymes have ...

OBJECTIVES To characterize plasmids encoding extended-spectrum β-lactamases (ESBLs) from a recent UK collection of clinical Escherichia coli isolates. METHODS The isolates comprised 118 ESBL producers referred from 54 laboratories. Plasmids were transferred by electroporation, and their incompatibility groups, associated addiction systems and resistance genes with the flanking genetic environ...