Molecular Species Composition Of Phosphatidylcholine Research Articles

Molecular species composition of phosphatidylcholines during the development of the avian embryo brain.

A comparative approach has been used to investigate the molecular species composition of phosphatidylcholine (PC) and its age variation throughout several developmental stages of chick and duck embryo brains. The brain PC consist of 15 major molecular species which do not undergo appreciable variation in their relative abundance either during embryonic development or between equivalent stages of maturation in the 2 avian species. In fact, a highly invariable molecular architecture of PC is shown in the developing organ. Molecular species containing saturated or monounsaturated fatty acids were dominant in all stages of development of the avian embryo brain. Among these molecular species, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine accounted for 75-80% of the total PC.

Effect of erucic acid on the phospholipid molecular species compositions of the rat heart and liver.

Erucic acid was not incorporated into phosphatidylcholine or phosphatidylethanolamine, but was into diphosphatidylglycerol and sphingomyelin in both the heart and liver of male Wistar rats fed erucic acid for 20 days. A remarkable difference between the heart and liver was found in the molecular species composition of phosphatidylcholine. The 1-stearoyl//2-arachidonoyl species of phosphatidylcholine in the heart was maintained at a higher level in rats fed the erucic acid diet than in rats fed a low fat diet. There was no difference in this molecular species content of cardiac and hepatic phosphatidylethanolamine between rats fed erucic acid and low fat diets. The level of erucic acid incorporated into triacylglycerols and free fatty acids in heart was higher than in the liver.

Lipid molecular species composition of thylakoid membranes

Lipid molecular species compositions of chloroplast thylakoid membranes of mesophyll cells from Spinacia oleracea, Glycine max, Oryza sativa and Zea mays and of bundle sheath cells from Zea mays have been quantitatively determined. No significant difference in the lipid molecular species composition was found among the five membrane sources. The predominant molecular species of monogalactosyldiacylglycerol was the 1-linolenoyl//2-linolenoyl species. The 1-linolenoyl//2-linolenoyl and 1-palmitoyl//2-linolenoyl species were the major molecular species of digalactosyldiacylglycerol. 6-Sulfoquinovosyldiacyl-glycerol was mainly composed of the palmitoyl//linolenoyl and palmitoyl//linoleoyl species. Almost all of the C-2 position of phosphatidylglycerol were esterified with the palmitoyl or Δ3- trans-hexadecenoyl residue. The molecular species compositions of phosphatidylcholine and phosphatidylinositol were basically similar to those of membranes in non-photosynthetic tissues.

Fatty acid and molecular species composition of rat brain phosphatidylcholine and -ethanolamine from birth to weaning.

AbstractThe fatty acid composition of diacyl phosphatidylcholine and phosphatidylethanolamine from the brain of rats 3, 6, 9, 12, 15, 18, and 21 days old were determined. In phosphatidylcholine, the relative amounts of stearic and oleic acid increased from 25% to 33% while the relative amounts of myristic, palmitic, and palmitoleic decreased from 65% to 50% during this time period. The same pattern was seen in phosphatidylethanolamine with stearic and oleic increasing from 38% to 49% and the shorter chain acids decreasing from 17% to 13%. The polyunsaturated fatty content of phosphatidylcholine was approximately 10% and increased slightly during the first 3 weeks, while the polyunsaturated content of phosphatidylethanolamine decreased from 44% to 37%. The molecular species composition of phosphatidylcholine and phosphatidylethanolamine was determined in brains of rats 3, 6, and 9 days old. The relative amounts of the molecular species remained nearly constant during this time period with phosphatidylcholine containing 35% saturated, 40% monoenoic, 6% dienoic, 11% tetraenoic, 2% pentaenoic, and 5% hexaenoic. Phosphatidylethanolamine contained 1% saturated, 8% monoenoic, 3% dienoic, 40% tetraenoic, 9% pentaenoic, and 37% hexaenoic species. Analysis of the fatty acid composition of the molecular species reveals that in phosphatidylcholine the polyunsaturated fatty acids 20∶4 and 22∶6 are predominately paired with 16∶0, while in the phosphatidylethanolamine these two unsaturated fatty acids are paired with 18∶0. Furthermore, dipalmitoyl phosphatidylcholine accounts for approximately 25% of the total molecular species of that lipid.