Phosphatidylcholines

Phosphatidylcholines are a class of phospholipids that are a major component of all cell membranes. They are also known as lecithins. A phosphatidylcholine molecule consists of a choline molecule esterified to a diacylglycerol, which in turn is esterified to two fatty acids. The hydrophilic choline head group and the hydrophobic fatty acid tails give phosphatidylcholines their amphipathic nature, allowing them to form lipid bilayers in aqueous environments.

These molecules play crucial roles in cellular function. They are essential for the structure and fluidity of cell membranes. Phosphatidylcholines are also precursors for the synthesis of other important signaling molecules, such as diacylglycerols, which are involved in signal transduction pathways. Furthermore, they are important for the absorption and transport of fats in the body. In the lungs, phosphatidylcholine is a major component of pulmonary surfactant, a substance that reduces surface tension and prevents the collapse of alveoli. Industrially, phosphatidylcholine is extracted from sources like soybeans and egg yolks and is used as an emulsifier in food products and as an ingredient in pharmaceuticals.