SUMMARY: The survival characteristics of washed ml 3 organisms, suspended in phosphate buffer, have been examined at the growth temperature. Mg markedly prolonged survival. High bacterial concentrations extended survival times, probably because Mg was excreted by the bacteria. Surviving organisms in some conditions showed prolonged division lags, especially in the absence of Mg. Salt concentration had little effect on survival within wide limits; the optimum pH value for survival was near 7.0. Survival times increased considerably at lower temperatures. Agitation and aeration tended to decrease survival. Death was not influenced by the phase of growth at which cells were harvested from a lactose-limiting medium. Casamino acids increased survival markedly in the presence of Mg; arginine was almost as effective as the complete mixture of amino acids while other individual amino acids tested gave only slight increases in survival times. Fermentable carbohydrates accelerated death of starving organisms irrespective of the growth phase from which they were harvested and of the limiting nutrient; the accelerated death was reduced by addition of Mg.


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