DNA REARRANGEMENTS AND PHENOTYPIC SWITCHING IN PROKARYOTES

Microorganisms have numerous strategies for coping with environmental changes. In many systems, a single cell has the capacity to generate a seemingly infinite array of phenotypic variants in just a few generat ions of growth. The resulting heterogeneous population is well equippe d for sudden environmental change; even if only a few cells in the pop ulation possess a phenotype needed for survival, these cells have the capacity to regenerate a similarly diverse population. Phenotypic swit ching in these systems usually results from high-frequency DNA rearran gements which are the subject of this review.