A simple method for the preparation of phosphatidylcholine labelled at 2-acyl position.

Phosphatidylcholine with a labelled acyl group at 2 position was prepared enzymatically from lysophosphatidylcholine and labelled fatty acids. Under optimal conditions, over 90% of [5,6,8,9,11,12,14,15-3H] arachidonic acid, [9,10-3H] palmitic acids, [1-14C] linoleic acid or [9,10-3H] oleic acid was incorporated into the phosphatidylcholine, and the incorporation was quantitative up to 500 nmol of [1-14C] linoleic acid. Analysis of the labelled phosphatidylcholine formed indicated that radioactivity was incorporated exclusively at 2-acyl position.