Resuscitation dynamics reveal persister partitioning after antibiotic treatment

Abstract

Bacteria can survive antibiotics by forming dormant, drug‐tolerant persisters. Persisters can resuscitate from dormancy after treatment and prolong infections. Resuscitation is thought to occur stochastically, but its transient, single‐cell nature makes it difficult to investigate. We tracked the resuscitation of individual persisters by microscopy after ampicillin treatment and, by characterizing their dynamics, discovered that Escherichia coli and Salmonella enterica persisters resuscitate exponentially rather than stochastically. We demonstrated that the key parameters controlling resuscitation map to the ampicillin concentration during treatment and efflux during resuscitation. Consistently, we observed many persister progeny have structural defects and transcriptional responses indicative of cellular damage, for both β‐lactam and quinolone antibiotics. During resuscitation, damaged persisters partition unevenly, generating both healthy daughter cells and defective ones. This persister partitioning phenomenon was observed in S. enterica , Klebsiella pneumoniae , Pseudomonas aeruginosa , and an E. coli urinary tract infection (UTI) isolate. It was also observed in the standard persister assay and after in situ treatment of a clinical UTI sample. This study reveals novel properties of resuscitation and indicates that persister partitioning may be a survival strategy in bacteria that lack genetic resistance. image Tracking and modelling single‐cell resuscitation dynamics of bacterial persisters shows that it is a drug‐dependent and non‐stochastic process. Persisters can partition cellular damage into healthy and nonviable daughter cells after antibiotic treatment. Persister resuscitation after treatment is exponential rather than stochastic. Persisters follow distinct trajectories during resuscitation: healthy, damaged, and failed. Persisters can partition into healthy and non‐viable daughter cells after treatment to survive. Persister partitioning occurs in E. coli , S. enterica , K. pneumoniae , and P. aeruginosa and in an E. coli in situ urinary tract infection sample.