What is "dipalmitoylphosphatidylcholine"

n. A phospholipid consisting of two palmitic acids, the major constituent of pulmonary surfactant.

Dipalmitoylphosphatidylcholine (DPPtdCho) is a phospholipid (and a lecithin) consisting of two palmitic acids attached of a phosphatidylcholine head-group and is the major constituent of many pulmonary surfactants. It is zwitterionic by virtue of having a negative charge on the phosphate group and a positive charge on the quaternary ammonium group.

It is thought that a lysophosphatidylcholine (lysoPC) acyltransferase may play a critical role in its synthesis. The identity of this acyltransferase has not yet been confirmed. Dipalmitoylphosphatidylcholine is an exception to the rule of thumb that biological phospholipids are synthesized with a saturated fat at the R1 position and an unsaturated fat at the R2 position.

It is also used for research purposes in studying liposomes, lipid bilayers, and model biological membranes and in the formation of reconstituted HDL (rHDL) particles.