Yeast Colony Survival Depends on Metabolic Adaptation and Cell Differentiation Rather Than on Stress Defense
Abstract
In contrast to liquid cultures of Saccharomyces cerevisiae, where population fitness depends on its ROS scavenging capability, the yeast cells growing in colonies capable of ammonia signaling use a broader protective strategy. Cells in colonies activate an alternative metabolism that prevents ROS production.
Colonies of the strain deficient in cytosolic superoxide dismutase Sod1p producing ammonia thus developed the same way as wt colonies. Colonies of strains deficient in Sod2p or cytosolic catalase Ctt1p failing in ammonia production and sufficient activation of the alternative metabolism have prominent developmental problems.
The data indicate that colony disorders are not accompanied by ROS burst but could be a consequence of metabolic defects.