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Characterization of mutations in the rpoB gene in naturally rifampin-resistant Rickettsia species.

ABSTRACT: Rickettsiae are gram-negative, obligately intracellular bacteria responsible for arthropod-borne spotted fevers and typhus. Experimental studies have delineated a cluster of naturally rifampin-resistant spotted fever group species. We sequenced the 4, 122- to 4,125-bp RNA polymerase beta-subunit-encoding gene (rpoB) from typhus and spotted fever group representatives and obtained partial sequences for all naturally rifampin-resistant species. A single point mutation resulting in a phenylalanine-to-leucine change at position 973 of the Rickettsia conorii rpoB sequence and present in all the rifampin-resistant species was absent in all the rifampin-susceptible species. rpoB-based phylogenetic relationships among these rickettsial species yielded topologies which were in accordance with previously published phylogenies.

SUBMITTER: Drancourt M

PROVIDER: S-EPMC89490 | biostudies-literature | 1999 Oct

REPOSITORIES: biostudies-literature

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Characterization of mutations in the rpoB gene in naturally rifampin-resistant Rickettsia species.

Drancourt M M Raoult D D

Antimicrobial agents and chemotherapy 19991001 10

Rickettsiae are gram-negative, obligately intracellular bacteria responsible for arthropod-borne spotted fevers and typhus. Experimental studies have delineated a cluster of naturally rifampin-resistant spotted fever group species. We sequenced the 4, 122- to 4,125-bp RNA polymerase beta-subunit-encoding gene (rpoB) from typhus and spotted fever group representatives and obtained partial sequences for all naturally rifampin-resistant species. A single point mutation resulting in a phenylalanine- ...[more]

PMID: 10508014

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