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Phosphoglycerides system

The different phosphoglycerides are often named by placing the constituent attached to the phosphate group after phosphatidyl , e.g. phosphatidyl choline (3-in-phosphatidylcholine or l,2-diacyl-sn-glycero-3-phosphoryl-choline). There are many phosphoglycerides because of the possible variation in the fatty acid chains, and when the full chemical structure is known, it should be used (e.g. l-palmitoyl-2-oleoyl-phosphatidylcholine). Nomenclature that entails the use of the DL system should be avoided. [Pg.417]

It is important to stress that these tests represent presumptive evidence for a vinyl ether containing phosphoglyceride (plasmalogen), but not a final proof of structure. Other tests that can be used in conjunction with the above qualitative detection systems are the phosphorus spray and sulfuric acid char... [Pg.111]

Phospholipase A2 Action. Incubation of phosphatidylserine with phospholipase A2 obtained from Crotalus adamanteus or Naja Naja snake venom will show that the serine-containing phosphoglyceride was smoothly and completely converted to a lysophosphatidylserine with liberation of 1 mol of fatty acid per mole of lipid P. The experimental procedure was the same as the one described before in this and in the previous chapter. The products of the reaction can be recovered by thin-layer chromatography on Whatman K6 plates in a solvent system of chloroform-acetone-methanol-acetic acid-water (4.5 2 1 1.3 0.5, v/v). [Pg.159]

There is no doubt that phosphatidylserine is active in the above reactions. However, in neither of these two systems has the importance of this phosphoglyceride in an in vivo system been defined. Certainly in the protein kinase C studies, there appeared to be no real attempt to explore the effect of mixtures of phospholipids (which might be encountered in the cell) on the kinase activity. In the blood coagulation pathway, it is well established that phosphatidylserine-phosphatidylcholine mixtures with the proper net negative charge are key in the formation of the active prothrombinase. Consequently, there is a general assumption by many investigators in this field that phosphatidylserine is the key component. [Pg.163]

It may well be correct that phosphatidylserine is integral to the reactions described. However, it is only a hope that at some point in the future it will be proven whether this is true for the in vivo situation. It will be of equal importance to establish in vivo whether mixtures of phosphoglycerides have an importance also. These are complex systems and it is obvious that further investigation is required to define the role of phosphatidylserine in these biologically important reactions. [Pg.163]

Manganese-deficiency has been reported to alter mitochondrial structure [428]. Mn(II) inhibits the replenishment of cell Ca(II) required for secretion of histamine by mast cells [429], and to alter the interferon system [430]. Mn(II) also affects the trans-bilayer movement of phosphoglycerides and Ca(II) [431], and influences the progressive motility of human sperm [432]. Mn(II) is likewise implicated in the aggregation of human platelets [433], in fibroblast spreading [434], and cell-substratum adhesion [435]. [Pg.108]

The phosphoglycerides combine within the same molecule both the hydrophilic (water-loving) phosphate ester groups and the hydrophobic fatty acid chains. They are therefore surface-active and play a role as emulsifying agents in biological systems, for example in the duodenum. Their surface-active nature also explains their function as constituents of various biological membranes. [Pg.45]

The phospholipases A2 ( PLA2s) hydrolyse specifically the n-2-fatty acyl ester bond of phosphoglycerides (Waite, 1987). PLA2S in animal systems are involved in many important processes, such as signal transduction, eicosanoid synthesis and inflammation. The available information about PLA2 from plant tissues is, however, very limited. [Pg.244]


See other pages where Phosphoglycerides system is mentioned: [Pg.244]    [Pg.88]    [Pg.33]    [Pg.90]    [Pg.94]    [Pg.124]    [Pg.130]    [Pg.140]    [Pg.163]    [Pg.168]    [Pg.184]    [Pg.189]    [Pg.222]    [Pg.1063]    [Pg.913]    [Pg.148]    [Pg.449]    [Pg.73]    [Pg.1063]    [Pg.380]    [Pg.141]    [Pg.445]    [Pg.366]    [Pg.196]    [Pg.808]    [Pg.315]    [Pg.401]    [Pg.475]    [Pg.6]    [Pg.11]    [Pg.12]    [Pg.3]    [Pg.339]    [Pg.340]   
See also in sourсe #XX -- [ Pg.13 ]




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Phosphoglycerides

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