Strong in vitro activities of two new rifabutin analogs against multidrug-resistant Mycobacterium tuberculosis.
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ABSTRACT:
SUBMITTER: Garcia AB
PROVIDER: S-EPMC2981290 | biostudies-literature | 2010 Dec
REPOSITORIES: biostudies-literature
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Strong in vitro activities of two new rifabutin analogs against multidrug-resistant Mycobacterium tuberculosis.
García Ana-Belén AB Palacios Juan J JJ Ruiz María-Jesús MJ Barluenga José J Aznar Fernando F Cabal María-Paz MP García José María JM Díaz Natalia N
Antimicrobial agents and chemotherapy 20100920 12
Two new rifabutin analogs, RFA-1 and RFA-2, show high in vitro antimycobacterial activities against Mycobacterium tuberculosis. MIC values of RFA-1 and RFA-2 were ≤0.02 μg/ml against rifamycin-susceptible strains and 0.5 μg/ml against a wide selection of multidrug-resistant strains, compared to ≥50 μg/ml for rifampin and 10 μg/ml for rifabutin. Molecular dynamic studies indicate that the compounds may exert tighter binding to mutants of RNA polymerase that have adapted to the rifamycins. ...[more]
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