Reduction of respiratory-chain cytochrome b by lactate in Saccharomyces cerevisiae.
Cytochrome b of yeast mitochondria can be reduced by a part of the electrons resulting from the oxidation of lactate enantiomers. 1. The respiration of D-lactate and L-lactate is 30-40% inhibited by antimycin A. 2. Reduction of cytochrome b is observed in submitochondrial particles in the presence of low concentration of D-lactate and L-lactate (half-optimal concentration of 4.7 mM and 2.4 mM respectively) in the presence of different bc1 inhibitors. 3. Reduction of cytochrome b and c1 occurs in purified complex III of yeast in the presence of L-lactate and added L-lactate: NAD+ oxidoreductase. 4. In the particles obtained from yeast grown in lactate the oxidation of L-lactate involves the reduction of a pigment absorbing at 558 nm.
D055598:Chemical Phenomena; D002621:Chemistry; D003573:Cytochrome b Group / Q000378:metabolism*; D004579:Electron Transport; D007773:Lactates / Q000494:pharmacology*; D008928:Mitochondria / Q000201:enzymology; D010084:Oxidation-Reduction / Q000187:drug effects; D012441:Saccharomyces cerevisiae / Q000201:enzymology*
D003573:Cytochrome b Group; D007773:Lactates