An Overview on Phase Variation, Mechanisms and Roles in Bacterial Adaptation.

In nature, bacteria are exposed to multiple stress conditions posing threat to their life. However, bacteria evolve constantly and employ myriad of genetic and phenotypic strategies for successful survival. One such adaptive process is phase variation - a random, frequent and reversible ON/OFF switching of contingency genes generating phenotypical variations within the bacterial population. Pathogenic and commensal bacteria make use of this heritable process as a tool for adaptation, generating intra-strain diversity and immune evasion. Unveiling molecular basis of this aspect of bacterial pathogenesis is vital in yielding significant implications to understand health and diseases. The current review was planned to overview this hot topic of research, its molecular basis and biological significance.