ubiquinone-8 + (R)-lactate <=> ubiquinol-8 + pyruvate
ubiquinone-8 + (r)-lactate <=> ubiquinol-8 + pyruvate
ubiquinone-8 + (R)-lactate <=> ubiquinol-8 + pyruvate
ubiquinone-8 + (r)-lactate <=> ubiquinol-8 + pyruvate