Evidence of an efflux pump in Serratia marcescens

Spontaneous mutants resistant to fluoroquinolones were obtained by exposing Serratia marcescens NIMA (wild-type strain) to increasing concentrations of ciprofloxacin both in liquid and on solid media. Frequencies of mutation ranged from 10-7 to 10-9. Active expulsion of antibiotic was explored as a...

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Detalhes bibliográficos
Autores: Berlanga Herranz, Mercedes, Vázquez, J. L., Borrell Hernández, Jordi, Montero Barrientos, Ma. Teresa, Viñas, Miquel
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2000
País:España
Recursos:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositório:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/54944
Acesso em linha:https://hdl.handle.net/2445/54944
Access Level:Acceso aberto
Palavra-chave:Resistència als medicaments
Antibiòtics
Serratia marcescens
Medicaments antibacterians
Drug resistance
Antibiotics
Descrição
Resumo:Spontaneous mutants resistant to fluoroquinolones were obtained by exposing Serratia marcescens NIMA (wild-type strain) to increasing concentrations of ciprofloxacin both in liquid and on solid media. Frequencies of mutation ranged from 10-7 to 10-9. Active expulsion of antibiotic was explored as a possible mechanism of resistance in mutants as well as changes in topoisomerase target genes. The role of extrusion mechanisms in determining the emergence of multidrug-resistant bacteria was also examined. Mutants resistant to high concentrations of fluoroquinolones had a single mutation in their gyrA QRDR sequences, whereas the moderate resistance in the rest of mutants was due to extrusion of the drug