SURF1, also known as surfeit 1, is a member of the SURF1 family, which includes the related yeast protein SHY1 and rickettsial protein RP733. This protein is localized to the inner mitochondrial membrane and thought to be involved in the biogenesis of the cytochrome c oxidase complex. Defect in SURF1 is a cause of Leigh syndrome, a severe neurological disorder that is commonly associated with systemic cytochrome c oxidase deficiency. Recombinant SURF1 protein was expressed in E.coli and purified by using conventional chromatography techniques.