Occurrence of an acyl-CoA:1-acylglycerophosphorylcholine acyltransferase in plant mitochondria.

In the presence of oleoyl-CoA, purified and intact mitochondria from potato tuber formed phosphatidylcholine from labeled lysophosphatidylcholine. The labeled oleoyl moiety of the acyl-CoA was also incorporated in the absence of exogenous lysolipids, such incorporation being largely increased by the addition of exogenous lysophosphatidylcholine. In the presence of various other lysophospholipids, no synthesis of the corresponding phospholipids was observed, suggesting a high specificity of the acyltransferase towards the acyl acceptor. This enzyme was chiefly located in the outer membrane of mitochondria. These results indicate that any acylglycerophosphorylcholine transferred from the endoplasmic reticulum to mitochondria may be acylated to phosphatidylcholine.