Subcellular and submitochondrial localization of the biosynthesis of cardiolipin and related phospholipids in rat liver

Abstract

1. 1. Intact mitochondria, inner and outer mitochondrial membranes and microsomes were isolated from rat liver and their purity determined with specific marker enzymes.

2. 2. Diphosphatidylglycerol synthesis was found exclusively in the inner mitochondrial membrane. Phosphatidylglycerol was predominantly synthesized in theinner membrane although a small contribution was noted in the outer membrane. CDP and dCDP diglyceride synthesis occurred primarily in the microsomal fraction.

3. 3. Diphosphatidylglycerol synthesis from phosphatidylglycerol was shown to require CDP diglyceride or dCDP diglyceride and a divalent cation (either Mg24, Mn2+ or Co2+). The reaction was strongly inhibited by nonionic detergents such as Triton X-100