Eagle Effect in Nonreplicating Persister Mycobacteria
نویسندگان
چکیده
We determined the microbicidal activities of antibacterials against nonreplicating Mycobacterium smegmatis grown in a starvation-based Loebel model for persistence. Whereas most drugs lost their activity, fluoroquinolones retained lethal potency. Dose-response characterizations showed a paradoxical more-drug-kills-less Eagle effect. Pretreatment of cultures with chloramphenicol blocked the lethal action of the gyrase inhibitors. These results suggest that fluoroquinolones at low concentrations trigger a protein synthesis-dependent cell death pathway and shut off this suicide pathway at elevated concentrations.
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عنوان ژورنال:
دوره 59 شماره
صفحات -
تاریخ انتشار 2015