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in the study design and draft of the manuscript. All authors read and approved the final manuscript.”
“Background Genetically identical bacterial cells can exhibit heterogeneity as the population bifurcates into distinct subpopulations. Such heterogeneity within clonal populations is a bet hedging strategy as a small fraction of a population is either prepared to survive adverse environmental conditions or sacrifice itself to enhance the likelihood of survival of clonal siblings. Examples of phenotypic heterogeneity include: development of competence and sporulation in Bacillus subtilis, lysogenic versus the lytic cycle of bacteriophage lambda, biofilm formation, toxin production and antibiotic persistence [1–4]. In Escherichia coli DNA damage induces the expression of more than 40 genes leading to arrest of cell division and the induction of DNA repair, prophages, toxin production and mutagenesis [5].