Metabolic Interconversion of Yeast Fractose-1,6-Bisphosphatase
After the addition of glucose to acetate- or ethanol-grown yeast cells a small group of enzymes is rapidly inactivated. This phenomenon has been called “catabolite inactivation” (Holzer 1976). Among other enzymes participating in gluconeogenesis, fructose-1,6-bisphosphatase is inactivated during catabolite inactivation (Harris and Ferguson 1967; Gancedo 1971). As shown in Fig. 1, the simultaneous presence of phosphofructokinase and fructose-1,6-bisphosphatase would lead after addition of glucose to a “futile cycle” which continously splits ATP to ADP and inorganic phosphate. The rapid inactivation of fructose-1,6-bisphosphatase after addition of glucose therefore protects the cells from ATP depletion. Experiments with specific antibodies have shown that catabolite inactivation of cytoplasmic malate dehydrogenase (Neeff et al. 1978), aminopeptidase I (Frey and Röhm 1979), fructose-1,6-bisphosphatase (Funayama et al. 1980), and phosphoenolpyruvate carboxykinase (Müller et al. 1981), is the result of proteolytic degradation of the respective enzymes.
KeywordsGlutamine Synthetase Phosphoenolpyruvate Carboxykinase Rapid Inactivation Futile Cycle Specific Catalytic Activity
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- Harris W, Ferguson JJ Jr (1967) Inactivation of yeast fructose diphosphatase in the course of catabolite repression. Fed Proc 26: 678.Google Scholar
- Holzer H (1976) Catabolite inactivation in yeast. Trends Biochem Sci (TIBS) 1: 178–181.Google Scholar
- Lenz A-G (1980) Studien zum Mechanismus der Katabolit-Inaktivierung in Hefe. Doctoral thesis, University FreiburgGoogle Scholar
- Mecke D, Wulff K, Holzer H (1966b) Metabolit-induzierte Inaktivierung von Glutaminsynthetase aus Escherichia coli im zellfreien System. Biochim Biophys Acta 128: 559–567.Google Scholar
- Müller M, Müller H, Holzer H (1981) Immunochemical studies on catabolite inactivation of phosphoenolpyruvate carboxykinase in Saccharomyces cerevisiae. J Biol Chem (in press)Google Scholar