[Evolution of several enzyme activities of Aureobasidium pullulans during the transition from yeast to mycelium induced by ethanol].

Some key enzyme activities from the energy metabolism of A. pullulans have been studied during the ethanol-induced yeast-to-mycelium transition. Both the mycelial and yeast-like forms showed greater glucose-6-phosphate dehydrogenase activity than phosphofructokinase. During the morphological transition, the most outstanding variations occurred in large cells (3 days), especially for citrate synthase, malate dehydrogenase and isocitrate lyase activities. However, similar variations were detected in cultures without glucose or ethanol, which showed no morphological transition. Therefore, the observed changes in the enzymatic activities may be attributed to the absence of glucose. As this is not sufficient to induce the morphological transition, we conclude that there is no evidence of a clear-cut relationship between morphology and the activity of the enzymes studied.