Rifampicin reduces susceptibility to ofloxacin in rifampicin-resistant Mycobacterium tuberculosis through efflux.

ABSTRACT:

Rationale

Central dogma suggests that rifampicin resistance in Mycobacterium tuberculosis develops solely through rpoB gene mutations.

Objective

To determine whether rifampicin induces efflux pumps activation in rifampicin resistant M. tuberculosis strains thereby defining rifampicin resistance levels and reducing ofloxacin susceptibility.

Methods

Rifampicin and/or ofloxacin minimum inhibitory concentrations (MICs) were determined in rifampicin resistant strains by culture in BACTEC 12B medium. Verapamil and reserpine were included to determine their effect on rifampicin and ofloxacin susceptibility. RT-qPCR was applied to assess expression of efflux pump/transporter genes after rifampicin exposure. To determine whether verapamil could restore susceptibility to first-

SUBMITTER: Louw GE 

PROVIDER: S-EPMC3698754 | biostudies-literature | 2011 Jul

REPOSITORIES: biostudies-literature