molecular biology, the choline/ethanolamine kinase family includes choline kinase ( EC 2.7.1.32 ) and ethanolamine kinase ( EC 2.7.1.82 ). Ethanolamine and choline are major membrane phospholipids , in the form of glycerophosphoethanolamine and glycerophosphocholine . Ethanolamine is also a component of the glycosylphosphatidylinositol (GPI) anchor, which is necessary for cell-surface