EFFECT OF POLY(3-HYDROXYBUTYRATE) (PHB) CONTENT ON THE STARVATION-SURVIVAL OF BACTERIA IN NATURAL-WATERS

The effect of poly(3-hydroxybutyrate) (PHB) content on the survival of wild-type strains and PHB negative mutants of Bacillus megaterium and Alcaligenes eutrophus in natural waters was studied. The survival str ategy of B. megaterium was dominated by the development of resistant f orms, but the number of the wild-type vegetative cells was higher than that of PHB mutant strain. In some environmental conditions the mutan t spores needed a heat shock for germination, a fact that suggests, fo r the first time, that PHB plays a role in this phenomenon. Survival o f A. eutrophus wild-type strain in all experiments was higher compared to the PHB mutant, and differences were significant. In raw river wat er, survival of both species was lower than in sterile river water.