AbstractsBiology & Animal Science

Vibrio marinus MP-1, an obligate psychrophilic marine bacterium, was severely damaged when heat-shocked in the presence of nutrients. Thermally induced leakage materials from cells tested for in the medium were 260 mμ absorbing material (nucleic acids), orcinol reacting material (RNA), ninhydrin reacting material (amino acids), protein, malic dehydrogenase, and glucose-6-phosphate dehydrogenase. Stationary phase cells were the most heat resistant as well as being more resistant to lysis and leakage after death. Log phase cells were the most thermolabile, and released intracellular materials after heating. There was an insignificant amount of leakage materials from cells held at 15 C (controls) while the 20, 23, and 25 C heat-shocked samples leaked increasingly more materials respectively. Leakage was shown to take place only after 95 percent of the cells were rendered nonviable. Leakage and lysis took place concommitantly.