Substratinduzierte cAMP‐Signale in Wildstämmen und Mutanten von Saccharomyces cerevisiae

Addition of glucose or other substrates to starved Saccharomyces cerevisiae cells triggers a cyclic AMP signal which induces the protein phosphorylating cascade. Before the addition of various substrates the wild‐type and mutant yeast strains were arrested at the G 1 phase of the cell division cycle by transferring the cells, grown at 26 °C to 36 °C in a synthetic medium without any substrate. After the temperature shift back to 26 °C different substrates were added and the cAMP levels were measured. The highest cAMP levels were observed immediately after the addition of the substrates. A relationship between the maximum growth rate of the individual strains or mutants at a given substrate and the intracellular cAMP level is discussed.