Fatal attraction in glycolysis: how Saccharomyces cerevisiae manages sudden transitions to high glucose.

In the model eukaryote Saccharomyces cerevisiae , it has long been known that a functional trehalose path-way is indispensable for transitions to high glucose conditions. Upon addition of glucose, cells with a de-fect in trehalose 6-phosphate synthase (Tps1 ), the first committed step in the trehalose pathway, display what we have termed an imbalanced glycolytic state; in this state the flux through the upper part of glycolysis out-paces that through the lower part of glycolysis. As a consequence, the intermediate fructose 1,6-bisphosphate (FBP) accumulates at low concentrations of ATP and inorganic phosphate (P