Intracellular and extracellular levels of cyclic AMP during the cell cycle of Saccharomyces cerevisiae

Using the techniques of centrifugal elutriation it was demonstrated that during the cell division cycle of the budding yeast Saccharomyces cerevisiae there are stage‐specific fluctuations in the intracellular concentration of adenosine 3′,5′‐cyclic monophosphate (cAMP). Results shown here indicate that the intracellular concentration of cAMP is at its highest during the division cycle, and its lowest immediately prior to and just after cell sepraration. Results also show the extrusion of extracellular cAMP into the medium by Saccharomyces cerevisiae, extracellular cAMP levels being ten to one hundred times higher than intracellular levels. During the cell of Saccharomyces cerevisiae the extracellular level of cAMP does not fluctuate.