Subinhibitory concentrations of penicillin increase the mutation rate to optochin resistance in Streptococcus pneumoniae.

CORTES, PAULO; PIÑAS, GERMÁN; ALBARRACIN ORIO, ANDREA; ECHENIQUE, JOSE

Oxford University Press

Lugar: Oxford ; Año: 2008 vol. 62 p. 973 - 973

p style="TEXT-ALIGN: justify; LINE-HEIGHT: 150%; MARGIN-RIGHT: -33.8pt" class="MsoNormal">Objectives:  The aim of this work was to study the effect of subinhibitory concentrations of penicillin, chloramphenicol and erythromycin on the mutation rate of Streptococcus pneumoniae. Methods: The mutation rate to rifampicin and optochin resistance was estimated using fluctuation analysis in three capsulated S. pneumoniae strains, cultured both with and without different subinhibitory antibiotic concentrations. The atpAC and rpoB mutations that conferred optochin and rifampicin resistance, respectively, were identified by DNA sequencing.