Functional replacement of yeast flavocytochrome b2 with bacterial l-lactate dehydrogenase

Using yeast genetic complementation, we show here that Rhodobacter sphaeroidesl-lactate dehydrogenase can functionally replace flavocytochrome b2 in Saccharomyces cerevisiae, only when a matrix-targeting signal of flavocytochrome b2 is fused with the bacterial enzyme. The recombinant l-lactate dehydrogenase may add alternative route of mitochondrial electron transport other than flavocytochrome b2.