Phospholipids are key molecules that contribute to the structural definition of cells and participate in the regulation of cellular processes. The major Phospholipids which occur in the membranes of mitotically growing S. cerevisiae (Saccharomyces cerevisiae) cells are PC (Phosphatidylcholine), PE (Phosphatidylethanolamine), PI/PtdIns (Phosphatidylinositol) and PS (Phosphatidylserine). Mitochondrial membranes contain PG (Phosphatidylglycerol) and CL (Cardiolipin/Diphosphatidylglycerol). Phospholipid biosynthesis is a complex process that contains a number of branch points. PS, PE and PC are synthesized from PA (Phosphatidate/Phosphatidic Acid) by the CDP-DAG (Cytidine Diphosphate-Diacylglycerol) pathway, while PE and PC are synthesized by the Kennedy (CDP-Choline (Cytidine Diphosphate-Choline) and CDP-Etn (Cytidine Diphosphate-Ethanolamine)) pathway. In general the major phospholipids like PC, PE, PS and PI (including CL) is synthesized by three branches of the [...]