Poster Presentation Australian Society for Microbiology Annual Scientific Meeting 2019

Preserving proteins during microbial dormancy speeds return to growth state (#246)

Jinki Yeom 1 , Eduardo Groisman 2
  1. Duke-NUS medical school, Singapore, SINGAPORE
  2. Microbial Pathogenesis, Yale School of Medicine, New Haven, CT, USA

All living organisms require nutrients to grow and reproduce.  When nutrient quantity or quality is low, organisms reduce their growth rate and enter a dormant state characterized by arrested physiological activity and critical for cell survival.  We now report that preserving proteins during dormancy speeds the return to a growth state.  We establish that the bacterium Salmonella entericareduces proteolysis by adenosine triphosphate (ATP)-dependent proteases by decreasing ATP amounts when starved for magnesium, carbon or nitrogen. In contrast, ATP reduction allows degradation of non-functional proteins to continue unimpeded thereby avoiding their potential toxic effects.  The yeast Saccharomyces cerevisiae also reduces ATP amounts and ATP-dependent proteolysis when starved for nutrients.  Drugs that increase ATP amounts delay entry into the growth state by promoting ATP-dependent proteolysis. Thus, the better the ability to preserve proteins during dormancy, the faster prokaryotes and eukaryotes exit the dormant state as soon as nutrients become available.  Starvation-promoted protein longevity likely also plays a role in the germination of bacterial spores and in antibiotic persistence.