Application Notes:
This product is a high purity phosphorylcholine (PC) that is acylated at the sn-1 and -2 positions with stearic acid, forming a
phosphorylcholine that is common in many animals and is therefore useful as a standard.1 PC is a major component of
biological membranes, especially in the outer leaflet, often composing almost 50% of the total phospholipids.2 It is a vital
component in membrane bilayers and is the main phospholipid circulating in plasma. PC plays an important role in
membrane-mediated cell signaling by generating diacylglycerols and phospholipids.3 Phospholipase D is an enzyme that
cleaves off the choline head group, converting PC to phosphatidic acid, while phospholipase C cleaves off the phosphate
group leaving diacylglycerol. PC is the biosynthetic precursor of sphingomyelin, phosphatidylethanolamine, lysophosphatidylcholine,
and platelet-activating factor. The choline headgroup is an essential nutrient in animals although it can
be synthesized by methylating phosphatidylethanolamine to phosphatidylcholine and then cleaving the headgroup with
phospholipase D.4 Tumor cells appear to have increased synthesis of PC and this may be a potential target for cancer therapy.
Another function of PC is the activation of enzymes such as the enzyme 3-hydroxybutyrate dehydrogenase which must be
bound to phosphatidylcholine before it can function optimally.
References:
1. E. Sim, P. Cullis, and R. Richards “Physical Studies on Phosphonium Phosphafidylcholine” Journal of Biochemistry, vol. 151 pp. 555-560, 1975
2. M. Billah and J. Anthes “The regulation and cellular functions of phosphatidylcholine hydrolysis” Biochemistry Journal, Vol. 269 pp. 281-291, 1990
3. J. Exton “Signaling through Phosphatidylcholine Breakdown” The Journal of Biological Chemistry, Vol. 265(1) pp. 1-4, 1990
4. Z. Li and D. Vance “Phosphatidylcholine and choline homeostasis” Journal of Lipid Research, Vol. 49 pp. 1187-1194, 2008