Fatty acid composition of phospholipids

Figure 20.18 The central dogma of molecular biology a summary of processes involved inflow of genetic information from DNA to protein. The diagram is a summary of the biochemical processes involved in the flow of genetic information from DNA to protein via RNA intermediates. This concept had to be revised following the discovery of the enzyme, reverse transcriptase, which catalyses information transfer from RNA to DNA (see Chapter 18). It may have to be modified in the future since changes in the fatty acid composition of phospholipids in membranes can modily the properties of proteins, and possibly their functions, independent of the genetic information within the amino acid sequence of the protein (See Chapters 7, 11 and 14).

TVurin, V.A., Berman, A.L., Ryzhova, M.P., Chelomin, V.P. and Korchagin, V.P. (1982). Fatty acid composition of phospholipids of the binary layer of photoreceptor membranes and aminophospholipids of rhodopsin microenvironment in cold and warm blooded vertebrates (In Russian). Zhumal Evolutsionnoy Biochimii i Physiologii 18,101-105. 

Table 1.12. Fatty acid composition of phospholipids from bovine milk...

The distribution and fatty acid composition of phospholipids in skim milk are similar to those in the MFGM. This has led to the suggestion that these membrane-associated constituents originate from a common cellular source and that the skim milk membranes, which contain much of the skim milk phospholipid pool, may be shed MFGM (for review, see Keenan and Dylewski, 1995). This assumption remains to be tested critically. 

Table DC. Individual fatty acid compositions of phospholipids isolated from raw foam and stream, foam, and foam-extract humic substances from the Suwannee River, in percentage...

Zalata, A.A., Christophe, A.B., Depuydt, C.E., Schoonjans, F. and Comhaire, F.H. (1998) The fatty acid composition of phospholipids of spermatozoa from infertile patients. Mol. Hum. Reprod. 4 111-118. 

Most of the reactions involved in lipid biosynthesis appear to be located in the smooth endoplasmic reticulum (SER), although several enzyme activities have also been detected in the Golgi complex. Because each enzyme is a membrane-associated protein with its active site facing the cytoplasm, the biosynthesis of phospholipid occurs at the interface of ER membrane and cytoplasm. The fatty acid composition of phospholipids changes somewhat after their synthesis. (Typically, unsaturated fatty acids replace the original saturated fatty acids incorporated during synthesis.) Most of this remodeling is accomplished by certain phospholipases and acyl transferases. Presumably, this process allows a cell to adjust the fluidity of its membranes. 

Nwosu, C.V. L.C. Boyd B. Sheldon. Effect of fatty acid composition of phospholipids on their antioxidant properties and activity index. /. Am. Oil Chem. Soc. 1997, 74, 293-297. 

The Fatty Acid Composition of Phospholipids Occurrence of Phospholipids in Foods... 

The fatty acid composition of phospholipids is not the same as that of TAG from the same material. The content of saturated fatty acids is usually higher, and the content of polyunsaturated fatty acids (PUFA) is often also high (Table 5.2), but differences exist even between phospholipid classes from the same material for example, in pig adipose tissue, phosphatidylethanolamines contain less saturated acids and more PUFA than phosphatidylcholines (Body, 1988) the content of eicosatetraenoic acid is par-... 

EPA Alters Phospholipid Composition of Cells. Because EPA may decrease TNF-a production through altering the membrane lipid composition of the cells, the phospholipid composition of the cells was assessed. THP-1 cells were preincubated with EPA for various time periods up to 24 h, and the long-chain fatty acid composition of phospholipids was analyzed. The levels of total n-3 PUFA increased from 3.47 to 13.54% and total n-6 PUFA decreased from 10.76 to 7.88% from 0 to 24 h (Table 1). EPA increased from 0.75 to 11.9% and AA decreased from 7.24% to 4.70% of total phospholipids (Table 1). 

Long-Chain Fatty Acid Composition of Phospholipids Isolated from THP-1 Cells Incubated with 60 piM of Eicosapentaenoic Acid... 

Fatty Acid Composition of Phospholipids in Cow Milk and Human MLlk Nippon Chikusan Gakkai-Ho 38(7) 277-285 (1967) CA 68 85479q... 

Figure 1 Changes in fatty acid composition of phospholipids during incubation of tulip bulb scale explants (+ palmitic, a stearic,...

COMPARISON OF FATTY ACID COMPOSITION OF PHOSPHOLIPIDS IN NORMAL AND HABITUATED SUGAR BEET CELL LINES... 

Methods of isolating intact sarcolemma free from admixture with other cell structures are necessary for precise study of its chemical and enzymic composition and for the investigation of possible changes in these in disease. A number of procedures have been devised to this end [97, 98], but it appears that there are difficulties still to be overcome. The sarcolemma may be expected to be rich in phospholipids which are important constituents of cell membranes. Changes have been reported in the fatty acid composition of phospholipids in muscle in human muscular dystrophy [99], in the autosomal dominant form of myotonia congenita [100], after denervation [101], and in muscular dystrophy in the mouse [102, 103]. Further work will be required to show whether the phospholipids of the sarcolemma are concerned in these abnormalities. The increased turnover of proteolipids [104] and increased biosynthesis of gangliosides [105] in denervated muscle may also represent changes in the characteristics of the sarcolemma. 

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