%0 Journal Article %A Dawes, E. A. %A Large, P. J. %T Effect of Starvation on the Viability and Cellular Constituents of Zymomonas anaerobia and Zymomonas mobilis %D 1970 %J Microbiology, %V 60 %N 1 %P 31-42 %@ 1465-2080 %R https://doi.org/10.1099/00221287-60-1-31 %I Microbiology Society, %X SUMMARY: Zymomonas anaerobia and Z. mobilis, grown on glucose + peptone + yeast-extract medium, degraded no endocellular carbohydrate, DNA and protein even in prolonged starvation. No significant qualitative changes in protein content during starvation were detected by disc gel electrophoresis of crude extracts. Both organisms had a high content of RNA (22% w/w) which was degraded on starvation. In Z. anaerobia RNA decreased linearly to 5% of the dry weight in 125 hr. With Z. mobilis, half the RNA was degraded in the first 24 hr of starvation after which time the decline was much slower. MgCl2 (33 mM) prevented RNA breakdown. During growth, the intracellular ATP concentration increased from 0.5 to 1.0 μg./mg. dry wt, but began to decrease exponentially in the last generation before growth ceased because of glucose exhaustion. Intracellular ATP content correlated with viability determined by slide culture. The addition of 33 mM-MgCl2 to the starvation medium did not affect ATP content, but increased viability. On prolonged starvation (up to 7 days), populations whose viability had fallen to 3% possessed unimpaired ability to produce ATP from glucose; only after even longer starvation periods was this ability impaired. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-60-1-31