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Updated: Jul 3, 2026

Mapping Metabolism: Monitoring Lactate Dehydrogenase Activity Directly in Tissue
Published on: June 21, 2018
Kinetic activation of yeast mitochondrial D-lactate dehydrogenase by carboxylic acids
Arnaud Mourier1, Julie Vallortigara, Edgar D Yoboue
1Université Bordeaux 2, Bordeaux cedex, France.
Abstract:
Aerobically grown yeast cells express mitochondrial lactate dehydrogenases that localize to the mitochondrial inner membrane. The D-lactate dehydrogenase is a zinc-flavoprotein with high acceptor specificity for cytochrome c, that catalyzes the oxidation of D-lactate into pyruvate. In this paper, we show that mitochondrial respiratory rate in phosphorylating or non-phosphorylating conditions with D-lactate as substrate is stimulated by carboxylic acids. This stimulation does not affect the yield of oxidative phosphorylation. Furthermore, this stimulation lies at the level of the D-lactate dehydrogenase. It is non-competitive, hyperbolic and its dimension is directly related to the number of carboxylic groups on the activator. The physiological meaning of such a regulation is discussed.
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