Fitness Cost and Compensatory Evolution in Levofloxacin-Resistant Mycobacterium aurum.
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ABSTRACT:
SUBMITTER: Pi R
PROVIDER: S-EPMC7526816 | biostudies-literature | 2020 Jul
REPOSITORIES: biostudies-literature
Publications
Fitness Cost and Compensatory Evolution in Levofloxacin-Resistant <i>Mycobacterium aurum</i>.
Pi Rui R Liu Qingyun Q Takiff Howard E HE Gao Qian Q
Antimicrobial agents and chemotherapy 20200722 8
We isolated spontaneous levofloxacin-resistant strains of <i>Mycobacterium aurum</i> to study the fitness cost and compensatory evolution of fluoroquinolone resistance in mycobacteria. Five of six mutant strains with substantial growth defects showed restored fitness after being serially passaged for 18 growth cycles, along with increased cellular ATP level. Whole-genome sequencing identified putative compensatory mutations in the <i>glgC</i> gene that restored the fitness of the resistant strai ...[more]
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