Describe the location and function of the various phospholipids.

Cardiolipin (CL), phosphatidylserine (PS), phosphatidylethanolamine (PE), phosphatidylcholine (PC), and phosphatidylinsitol (PI),┬áCardiolipin (diphosphatidylglycerol) (CL) – located in the inner mitochondrial membrane. It has an anionic charge and the function is unknown, as cardiolipin is not involved in the immune or coagulation systems.

Phosphatidylserine (PS) – located in the inner platelet membrane and, during activation, the exterior platelet membrane. It carries an anionic charge, and is the primary phospholipid which promotes the anticoagulant protein C pathway, providing feedback inhibition of thrombin formation.

Phosphatidylethanolamine (PE) – located in both the interior and exterior of cell membranes. It carries a neutral (zwitterionic) charge, and promotes the anticoagulant protein C pathway, but to a lesser degree than PS.

Phosphatidylcholine (PC) – located in the interior and exterior of cell membranes. It carries a neutral charge, and promotes the anticoagulant protein C pathway, but to a lesser degree than PS.

Phosphatidylinsitol (PI) – located in the interior and exterior of cell membranes. It carries a cationic charge, and promotes the anticoagulant protein C pathway, but to a lesser degree than PS.