HOW DO NONDIFFERENTIATING BACTERIA ADAPT TO STARVATION

Non-differentiating bacteria adapt to starvation induced growth arrest by a complex turn-on/turn-off pattern of protein synthesis. This resp onse shows distinct similarities with those of spore formation in diff erentiating organisms. A substantial amount of information on the non- growth biology of non-differentiating bacteria can be derived from stu dies on Vibrio strains. One important result is that carbon rather tha n nitrogen or phosphorus starvation leads to the development of a star vation and stress resistant cell in these organisms. Hence, we have at tempted to characterize the carbon starvation stimulon. By the use of two-dimensional gel electrophoresis of pulse-labelled cells and transp oson mutagenesis, using reporter gene constructs, the identity and fun ction of some members of the carbon starvation stimulon have been eluc idated. Moreover, regulatory genes of the starvation response have bee n identified with these techniques. Current studies primarily address the identity and function of these genes. The role of transcript modif ication and stability for both long term persistence during starvation as well as the efficient recovery of cells which occurs upon nutrient addition is also addressed. It is suggested that an understanding of the functionality of the translational machinery is essential for the understanding of these adaptive pathways. This contribution also discu sses the diversity of the differentiation-like response to starvation in different bacteria and whether a general starvation induced program me exists.