THE PEL1 MUTANT OF SACCHAROMYCES-CEREVISIAE IS DEFICIENT IN CARDIOLIPIN AND DOES NOT SURVIVE THE DISRUPTION OF THE CHO1 GENE ENCODING PHOSPHATIDYLSERINE SYNTHASE

Cells of the pell mutant of Saccharomyces cerevisiae were found to con tain an extremely low content of cardiolipin, a decreased level of pho sphatidylcholine and an increased level of phosphatidylinositol. Disru ption of the PELl gene in cells containing a null mutation in the CHOl gene was lethal. Despite its putative functional homology with CHOl, the overexpression of the PELl gene in the cho null mutant did not res tore the wild-type properties of the transformed cells and failed to s timulate the incorporation of L-[3-H-3]serine into total lipids of the intact yeast cells.