Glucose Effect on Energetic Metabolism of Yeast - Glucose Repression and Catabolite Inactivation

Srđan Novak and Vladimir Marić

Prehrambeno-biotehnološki fakultet, Sveučilište u Zagrebu, Zagreb

Article history:
Received January 15, 1993
Accepted February 18, 1993

Summary:
The presence of glucose in the surrounding of the yeast cell blocks the consumption of other carbon sources within the cell. This phenomenon is a result of an action of the two regulatory mechanisms. The first mechanism, glucose or catabolite repression, acts on the level of the enzyme synthesis, so the glucose prevents transcription of the genes that are responsible for the metabolism of other carbon sources. The second mechanism, catabolite inactivation, leads to inactivation of enzymes already present within the cell if they are not needed or could be harmful for the cell. Intensive research in recent years profoundly extended the knowledge about these two regulatory mechanisms indicating their exceptional complexity on the molecular level. Therefore, it is not surprising that some essential elements are still not fully understood.