Phosphatidylserine functions

Included among drugs that alter the permeability of the membrane are phosphatidylserine, S-adenosylmethionine, and ganglioside extracts. Phosphatidylserine, produced from purified extracts of bovine brain cortex, alters the permeability and functionality of the neuronal membrane. A study... 

The diacylglycerols released by phospholipase C diffuse laterally through the bilayer and, together with the incoming Ca2+, activate protein kinases C. These kinases also require phosphatidylserine for their activity and phosphorylate serine and threonine side chains in a variety of proteins.329 330b They are stimulated by the released unsaturated diacylglycerols. In addition protein kinases C can be activated by phorbol esters, which are the best known tumor promoters (Box 11-D). The diacylglycerol requirement favors a function for these protein kinases in membranes. They also appear to cooperate with calmodulin to activate the Ca2+-dependent contraction of smooth muscle.330... 

Platelet participation in normal hemostasis. The hemostatic plug is the specific response to external vessel lesion and depends on the extent of vessel wall damage, the specific interaction between endothelial cells and activated platelets, release of the contents of platelets intracellular granules in response to activation, the conjoint activity of activated factor Vll and platelet agonists, and the open conditions of blood flow. After activation, platelets also produce the external ization of membrane phosphatidylserine through the flip-flop mechanism that will support the function of the prothrombinase complex ending in thrombin generation and local clot formation. 

It is now widely accepted that atherosclerosis is a chronic inflammatory arterial disease associated with risk factors, platelet, and other blood cells activities and their interactions with subendothelial cells, Activated platelets release active components from citosol and induce the externalization of phosphatidylserine through the flip-flop mechanism (23) that supports the function of the prothrombinase complex ending in thrombin generation,... 

Fig. 5.13 Phosphatidylserine (PS) dependence of Ca2+-stimulated PKC activity as a function of palmitoyl- (Po), oleoylphosphatidylserine POPS concentration in the POPS/PE LUVs. Enzyme activity measured relative to 100% POPS. Total phospholipid concentration in the incubation...

Fig. 5.20 Changes in drug proton relaxation rate (1 /T2) as a function of increasing concentration of bovine brain phosphatidylserine (BBPS) alone and after addition of CaCI2- The spin systems measured are indicated by arrows on the drug structures. (Reprinted from Fig. 6 of ref. 117 with permission from Bertelsmann-Springer.)...

Kodaki, T., Nikawa, J., Hosaka, K., and Yamashita, S., 1991b, Functional analysis of the regulatory region of the yeast phosphatidylserine synthase gene, PSS. J. Biochem. 173 7992-7995. 

Lecithin, an edible by-product of oil processing possessing a variety of useful functionalities, is primarily a mixture of phospholipids such as phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, and phospha-tidic acid and contains minor quantities of other water-soluble or hydratable components such as glycolipids and oligosaccharides (78). The degumming of oil with... 

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