Effect of home exposure to Staphylococcus aureus on asthma in adolescents.
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ABSTRACT:
SUBMITTER: Davis MF
PROVIDER: S-EPMC5758414 | biostudies-literature | 2018 Jan
REPOSITORIES: biostudies-literature
Publications
Effect of home exposure to Staphylococcus aureus on asthma in adolescents.
Davis Meghan F MF Ludwig Shanna S Brigham Emily P EP McCormack Meredith C MC Matsui Elizabeth C EC
The Journal of allergy and clinical immunology 20170721 1
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Project description:Bacterial persister cells are phenotypic variants that exhibit a transient non-growing state and antibiotic tolerance. Here we provide in vitro evidence of Staphylococcus aureus persisters within infected host cells. We show that the bacteria surviving antibiotic treatment within host cells are persisters, displaying biphasic killing and reaching a uniformly non-responsive, non-dividing state when followed at the single-cell level. This phenotype is stable but reversible upon antibiotic removal. Intracellular S. aureus persisters remain metabolically active, but display an altered transcriptomic profile consistent with activation of stress responses, including the stringent response as well as cell-wall stress, SOS and heat-shock responses. These changes are associated with multidrug tolerance after exposure to a single antibiotic. We hypothesize that intracellular S. aureus persisters may constitute a reservoir for relapsing infection, and could contribute to therapeutic failures.
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