title: Extended-spectrum β-lactamases in Enterobacteriaceae isolated in Brazil carry distinct types of plasmid-mediated quinolone resistance genes.
abstract: One hundred and six nalidixic acid-resistant Enterobacteriaceae isolates from two Brazilian hospitals isolated from June to October 2010 were evaluated to characterize the co-existence of plasmid-mediated quinolone resistant (PMQR) and extended-spectrum β-lactamase (ESBL) determinants. The qnr genetic environment was determined by PCR and sequencing. Conjugation and hybridization experiments determined whether qnr-carrying plasmids were self-transferable. The aac(6')-Ib-cr and qepA genes were also screened. Thirteen qnr-like genes (12.3 %) were identified, with qnrB1 the most common, followed by qnrS1, qnrB2 and qnrB19. No qnrA, qnrC, qnrD or qepA determinant was detected. All qnr-positive strains possessed chromosomal substitutions in gyrase- and topoisomerase-encoding genes and four harboured a aac(6')-Ib-cr gene. The co-production of blaCTX-M was observed in ten qnr-positive strains. These results indicate the dissemination of PMQR genes shown in clinical isolates from Brazil, and their co-existence with ESBL genes emphasizes the complexity of plasmid-mediated resistance determinants among Enterobacteriaceae.
authors.affiliation: Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade Federal de Alfenas - UNIFAL, Minas Gerais, Brazil.
authors.forename: André L M
authors.initials: ALM
authors.lastname: Viana
authors.affiliation: Laboratório ALERTA, Disciplina de Infectologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Cayô
authors.affiliation: Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade Federal de Alfenas - UNIFAL, Minas Gerais, Brazil.
authors.forename: Cassia C
authors.initials: CC
authors.lastname: Avelino
authors.affiliation: Laboratório ALERTA, Disciplina de Infectologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil.
authors.forename: Ana C
authors.initials: AC
authors.lastname: Gales
authors.affiliation: Departamento de Microbiologia e Imunologia, Universidade Federal de Alfenas - UNIFAL, Minas Gerais, Brazil.
authors.forename: Marília C
authors.initials: MC
authors.lastname: Franco
authors.affiliation: Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil.|Departamento de Análises Clínicas e Toxicológicas, Faculdade de Ciências Farmacêuticas, Universidade Federal de Alfenas - UNIFAL, Minas Gerais, Brazil.
authors.forename: Luciene A R
authors.initials: LAR
authors.lastname: Minarini
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001938:Brazil; D002439:Cefotaxime / Q000494:pharmacology; D002876:Chromosomes, Bacterial / Q000235:genetics / Q000378:metabolism; D024881:Drug Resistance, Bacterial; D004755:Enterobacteriaceae / Q000187:drug effects / Q000201:enzymology* / Q000302:isolation & purification; D005798:Genes, Bacterial; D008826:Microbial Sensitivity Tests; D009154:Mutation; D009268:Nalidixic Acid / Q000494:pharmacology*; D010957:Plasmids / Q000235:genetics* / Q000378:metabolism; D013530:Surgical Wound Infection / Q000382:microbiology; D014556:Urine / Q000382:microbiology; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D009268:Nalidixic Acid; D001618:beta-Lactamases; D002439:Cefotaxime