CATABOLIC REPRESSION AND MICROBIAL MODELING FOR THE YEAST SACCHAROMYCES-CEREVISIAE

The mechanism of catabolic repression is not yet fully understood. Oxygen seems to control the level of cytochrome in the in situ state. The level of glucose seems to control other enzymes; glucose by itself does not repress the catabolism. An unidentified product of glucose metabolism is believed to be involved. In bacterial cultures, there is convincing evidence that cyclic AMP is involved and this operates at the level of gene transcription. In yeast, it is not clear. The level of C(AMP) is found to be reduced with catabolic repressed cells, but there is little evidence to conclude that C(AMP) acts at the transcription level [1]. There are results to indicate that it acts at the translational level or enzyme activation phase in yeast. In order to understand this mechanism, the bio-energetics of yeasts grown under catabolic repression is analyzed with the data available [2] and appended.