Time-Lapse Epifluorescence Microscopy Imaging of Pseudomonas aeruginosa and Staphylococcus aureus Heterogeneous Phenotypes.

Antibiotic persistence is a phenomenon in which a small number of bacterial cells in a genetically susceptible population survive antibiotic treatment that kills the other genetically identical cells. Bacterial persisters can resume replication once antibiotic treatment ends and are commonly thought to underlie clinical treatment failure. Recent work harnessing the power of time-lapse fluorescence microscopy, in which bacteria are labeled with fluorescent transcriptional reporters, translational reporters, and/or dyes for a variety of cellular features, has advanced our understanding of Escherichia coli persisters beyond what could be learned from population-level antibiotic survival assays.

Agar and agarose used for Staphylococcus aureus biofilm cultivation impact fluoroquinolone tolerance.

Aims: Staphylococcus aureus is an opportunistic pathogen whose treatment is further complicated by its ability to form biofilms. In this study, we examine the impact of growing S. aureus biofilms on different polymerizing surfaces, specifically agar and agarose, on the pathogen's tolerance to fluoroquinolones.