SURVIVAL AND CHEMICAL ALTERATIONS IN PSEUDOMONAS-SYRINGAE ATCC-12271 STARVED IN BUFFER

Pseudomonas syringae cells survived for a considerable time in PIPES b uffer, mimicking their behaviour in artificially inoculated plants. Th e survival of P. syringae in buffer is intermediate between human, mar ine and soil bacteria. Starvation resulted in a decrease in the cellul ar content of hexoses, proteins and free and purine-bound ribose. In t he supernatant, the concentration of inorganic phosphate and ammonia c ontinuously increased with time, but the concentration of hexoses, pro teins, free and purine-bound ribose, and UV-absorbing materials, incre ased up to 2-4 days of starvation, and then decreased. The results sug gest that protein was the most expendable substrate during starvation, and that cells utilized the molecules previously released to the exte rnal medium, as substrates for endogenous metabolism. This characteris tic, and the fact that after a few days of starvation, endogenous oxyg en consumption proceeded at a low rate, are likely to be advantageous for survival of these cells during starvation.