This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Flikweert, M. T. Articles by Pronk, J. T. Search for Related Content PubMed PubMed Citation Articles by Flikweert, M. T. Articles by Pronk, J. T. Agricola Articles by Flikweert, M. T. Articles by Pronk, J. T.

 Previous Article  |  Next Article 

Appl. Environ. Microbiol., Sep 1997, 3399-3404, Vol 63, No. 9
Copyright © 1997, American Society for Microbiology

Metabolic responses of pyruvate decarboxylase-negative Saccharomyces cerevisiae to glucose excess

MT Flikweert, JP van Dijken and JT Pronk
Department of Microbiology and Enzymology, Kluyver Laboratory of Biotechnology, Delft University of Technology, The Netherlands.

In Saccharomyces cerevisiae, oxidation of pyruvate to acetyl coenzyme A can occur via two routes. In pyruvate decarboxylase-negative (Pdc-) mutants, the pyruvate dehydrogenase complex is the sole functional link between glycolysis and the tricarboxylic acid (TCA) cycle. Such mutants therefore provide a useful experimental system with which to study regulation of the pyruvate dehydrogenase complex. In this study, a possible in vivo inactivation of the pyruvate dehydrogenase complex was investigated. When respiring, carbon-limited chemostat cultures of wild- type S. cerevisiae were pulsed with excess glucose, an immediate onset of respiro-fermentative metabolism occurred, accompanied by a strong increase of the glycolytic flux. When the same experiment was performed with an isogenic Pdc- mutant, only a small increase of the glycolytic flux was observed and pyruvate was the only major metabolite excreted. This finding supports the hypothesis that reoxidation of cytosolic NADH via pyruvate decarboxylase and alcohol dehydrogenase is a prerequisite for high glycolytic fluxes in S. cerevisiae. In Pdc- cultures, the specific rate of oxygen consumption increased by ca. 40% after a glucose pulse. Calculations showed that pyruvate excretion by the mutant was not due to a decrease of the pyruvate flux into the TCA cycle. We therefore conclude that rapid inactivation of the pyruvate dehydrogenase complex (e.g., by phosphorylation of its E1 alpha subunit, a mechanism demonstrated in many higher organisms) is not a relevant mechanism in the response of respiring S. cerevisiae cells to excess glucose. Consistently, pyruvate dehydrogenase activities in cell extracts did not exhibit a strong decrease after a glucose pulse.

This article has been cited by other articles:

• Heux, S., Sablayrolles, J.-M., Cachon, R., Dequin, S. (2006). Engineering a Saccharomyces cerevisiae Wine Yeast That Exhibits Reduced Ethanol Production during Fermentation under Controlled Microoxygenation Conditions. Appl. Environ. Microbiol. 72: 5822-5828 [Abstract] [Full Text]  
• Todisco, S., Agrimi, G., Castegna, A., Palmieri, F. (2006). Identification of the Mitochondrial NAD+ Transporter in Saccharomyces cerevisiae. J. Biol. Chem. 281: 1524-1531 [Abstract] [Full Text]  
• van Maris, A. J. A., Geertman, J.-M. A., Vermeulen, A., Groothuizen, M. K., Winkler, A. A., Piper, M. D. W., van Dijken, J. P., Pronk, J. T. (2004). Directed Evolution of Pyruvate Decarboxylase-Negative Saccharomyces cerevisiae, Yielding a C2-Independent, Glucose-Tolerant, and Pyruvate-Hyperproducing Yeast. Appl. Environ. Microbiol. 70: 159-166 [Abstract] [Full Text]  
• van Maris, A. J. A., Luttik, M. A. H., Winkler, A. A., van Dijken, J. P., Pronk, J. T. (2003). Overproduction of Threonine Aldolase Circumvents the Biosynthetic Role of Pyruvate Decarboxylase in Glucose-Limited Chemostat Cultures of Saccharomyces cerevisiae. Appl. Environ. Microbiol. 69: 2094-2099 [Abstract] [Full Text]  
• Rodrigues, F., Côrte-Real, M., Leão, C., van Dijken, J. P., Pronk, J. T. (2001). Oxygen Requirements of the Food Spoilage Yeast Zygosaccharomyces bailii in Synthetic and Complex Media. Appl. Environ. Microbiol. 67: 2123-2128 [Abstract] [Full Text]  
• Boubekeur, S., Bunoust, O., Camougrand, N., Castroviejo, M., Rigoulet, M., Guerin, B. (1999). A Mitochondrial Pyruvate Dehydrogenase Bypass in the Yeast Saccharomyces cerevisiae. J. Biol. Chem. 274: 21044-21048 [Abstract] [Full Text]  
• Luttik, M. A. H., Overkamp, K. M., Kotter, P., de Vries, S., van Dijken, J. P., Pronk, J. T. (1998). The Saccharomyces cerevisiae NDE1 and NDE2 Genes Encode Separate Mitochondrial NADH Dehydrogenases Catalyzing the Oxidation of Cytosolic NADH. J. Biol. Chem. 273: 24529-24534 [Abstract] [Full Text]