Participation of microsomal CDP-diglycerides in mitochondrial biosynthesis of 
phosphatidylglycerol was studied by [3H]palmitoyl, [14C]linoleoyl, and 
[14C]arachidonoyl CDP-diglycerides and [3H]CDP-diglycerides which were bound to 
microsomal membranes, incubated with unlabelled mitochondrial membranes, and 
further incubated in the presence of radioactive sn-glycero-3-phosphate under 
conditions required for mitochondrial phosphatidylglycerol biosynthesis. Ten to 
15% of microsomal radioactive CDP-diglycerides was transferred to mitochondrial 
membranes and incorporated into mitochondrial radioactive lipids identified as 
phosphatidylglycerol, phosphatidylglycerophosphate, and, when [14C]linoleoyl 
CDP-diglycerides were used, diphosphatidylglycerol (cardiolipin).