The starvation-stress response of .

The starvation-stress response of was investigated and characterized with regard to changes in cell morphology and the ability of to survive starvation, heat shock, exposure to HO and exposure to ethanol. The ability of to survive exposal to the latter three stresses after initiation of starvation was also examined. Results of these experiments indicated that when starved for carbon, nitrogeand phosphorus, the c.f.u. of declined by about one order of magnitude over the first 5-7 d of starvation; starvation for an additional 3-4 weeks resulted in a gradual decline in c.f.u. by another order of magnitude. Examination of starved cells by electron microscopy revealed that while most cells formed spherical ultramicrocells during starvation, some of the cells elongated to form short spirals. While cross-protection against other stresses such as oxidative stress (exposure to HO) and exposure to ethanol developed only a small degree of resistance to heat shock developed. Moreover, in all cases these resistances disappeared during prolonged starvation (usually > 5 d). Additionally, the rate of protein synthesis per c.f.u., measured by [S]methionine incorporation, declined during the initial 6 h of starvation and increased to over 70% of the rate measured in exponentially growing cells by 5 d of starvation. It was concluded that the starvation-stress response of differs significantly from those starvation responses reported for other bacteria, including responses displayed by other species.