Tags: Chemical Compound, Chemical Substance.
Phosphatidylserine (abbreviated Ptd-L-Ser or PS) is a phospholipid component usually kept on the inner-leaflet (the cytosolic side) of cell membranes by an enzyme called flippase. When a cell undergoes apoptosis phosphatidylserine is no longer restricted to the cytosolic part of the membrane but becomes exposed on the surface of the cell.
