The mitochondrial FAD transporter, Flx1p, is a member of the mitochon-drial carrier family responsible for FAD transport inSaccharomyces cerevi-siae. It has also been suggested that it has a role in maintaining the normal activity of mitochondrial FAD-binding enzymes, including lipoamide dehydrogenase and succinate dehydrogenase flavoprotein subunit Sdh1p.