HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 277, Issue 31, 27991-27995, August 2, 2002

This Article Full Text Full Text (PDF) All Versions of this Article: 277/31/27991    most recent M204079200v1 Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Påhlman, I.-l. Articles by Rigoulet, M. Search for Related Content PubMed PubMed Citation Articles by Påhlman, I.-l. Articles by Rigoulet, M. Social Bookmarking                      What's this?

Kinetic Regulation of the Mitochondrial Glycerol-3-phosphate Dehydrogenase by the External NADH Dehydrogenase in Saccharomyces cerevisiae^*

Inga-lill Påhlman, Christer Larsson^§, Nicole Averét^¶, Odile Bunoust^¶, Samira Boubekeur^¶, Lena Gustafsson^§, and Michel Rigoulet^¶**

From the  Department of Cellular and Molecular Biology-Microbiology, Lundberg Laboratory, Gothenburg University, Box 462, SE-405 30 Gothenburg, Sweden, the ^§ Department of Molecular Biotechnology, Lundberg Laboratory, Chalmers University of Technology, Box 462, SE-405 30 Gothenburg, Sweden, and the ^¶ Institut de Biochimie et Génétique Cellulaires, University of Bordeaux 2, 1 rue Camille Saint-Saens, 33077 Bordeaux cedex, France

In the yeast Saccharomyces cerevisiae, the two most important systems for conveying excess cytosolic NADH to the mitochondrial respiratory chain are external NADH dehydrogenase (Nde1p/Nde2p) and the glycerol-3-phosphate dehydrogenase shuttle. In the latter system, NADH is oxidized to NAD+ and dihydroxyacetone phosphate is reduced to glycerol 3-phosphate by the cytosolic Gpd1p; glycerol 3-phosphate gives two electrons to the respiratory chain via mitochondrial glycerol-3-phosphate dehydrogenase (Gut2p)-regenerating dihydroxyacetone phosphate. Both Nde1p/Nde2p and Gut2p are located in the inner mitochondrial membrane with catalytic sites facing the intermembranal space. In this study, we showed kinetic interactions between these two enzymes. First, deletion of either one of the external dehydrogenases caused an increase in the efficiency of the remaining enzyme. Second, the activation of NADH dehydrogenase inhibited the Gut2p in such a manner that, at a saturating concentration of NADH, glycerol 3-phosphate is not used as respiratory substrate. This effect was not a consequence of a direct action of NADH on Gut2p activity because both NADH dehydrogenase and its substrate were needed for Gut2p inhibition. This kinetic regulation of the activity of an enzyme as a function of the rate of another having a similar physiological function may be allowed by their association into the same supramolecular complex in the inner membrane. The physiological consequences of this regulation are discussed.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				O. Bunoust, A. Devin, N. Averet, N. Camougrand, and M. Rigoulet Competition of Electrons to Enter the Respiratory Chain: A NEW REGULATORY MECHANISM OF OXIDATIVE METABOLISM IN SACCHAROMYCES CEREVISIAE J. Biol. Chem., February 4, 2005; 280(5): 3407 - 3413. [Abstract] [Full Text] [PDF]