The starvation-stress response of Vibrio (Listoneila) anguillarum

Abstract

Summary: The starvation-stress response of Vibrio (Listonella) anguillarum was investigated and characterized with regard to changes in cell morphology and the ability of V. anguillarum to survive starvation, heat shock, exposure to H2O2 and exposure to ethanol. The ability of V. anguillarum 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 V. anguillarum 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 H2O2) 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 [35S]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 V. anguillarum differs significantly from those starvation responses reported for other bacteria, including responses displayed by other Vibrio species.