ABSTRACT
Bacterial populations are constantly facing barriers that restrict their growth. Clinical and veterinary uses of antibiotics are but two barriers to growth, as host defenses and adverse environmental conditions usually keep microbial populations in check. How successful a microbe is at surviving the diverse challenges of ever-changing environments ultimately rests upon the relative diversity within the microbial population at large. Subpopulations of mutators, which exist in all bacterial populations, are a prolific source of such diversity. We discuss here how a particular set of mutators that are defective in methyl-directed mismatch repair provides multiple mechanisms for bacteria to evade the manifold barriers they face on the course to successful infection.
