Choline phosphoglyceride

In another detailed study on the influence of the substituent at the C-l position in sn-3 choline phosphoglycerides, Waku and Nakazawa (1972) investigated the catalytic behavior of the phospholipase D of cabbage and carrot. Their findings showed that either source exhibited high activity toward a diacylphosphoglyceride, with a much lower rate of hydrolysis toward an alkylacyl- and alkenylacylphosphoglyceride. 

At the present time there is no satisfactory route to isolation of diacyl-, alkylacyl-, or alkenylacylcholine phosphoglycerides as individual components— for example, only the diacyl type or the alkylacyl form, and so on. In general, a differential analytical approach must be invoked and this will be discussed later. However, since diacylphosphatidylcholine has been discussed, proof of structure of ether-linked choline phosphoglycerides as individual species will be described as well as some of their structural features. Later, as the big picture emerges, the route to analysis of a naturally occurring mixture will be examined. 

Martinez M. Ballabriga A, Gil-Gibernau JJ. Lipids of the developing human retina I. Total fatty acids, plasmologens, and fatty acid compostition of ethanolamine and choline phosphoglycerides. J Neurosci Res 1988- 20 484-490. 

Polar phospholipid of plasma is mainly choline phosphoglyceride, hence we used red blood cells (R.B.C.s) for ethanolamine phosphoglyceride analysis. Fetal material was obtained at second trimester. 

Values are the average S.E. of determinations carried out on 4 samples. EPG = ethanolamine phosphoglyceride CPG = choline phosphoglyceride SPG = serine phosphoglyceride IPG = inositol phosphoglyceride. ... 

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. 

The anaemia in B deficiency is caused by an inability to produce sufficient of the methylating agent S-adenosyhnethionine. This is required by proliferating cells for methyl group transfer, needed for synthesis of the deoxythymidine nucleotide for DNA synthesis (see below and Chapter 20). This leads to failure of the development of the nucleus in the precursor cells for erythrocytes. The neuropathy, which affects peripheral nerves as well as those in the brain, is probably due to lack of methionine for methyl transfer to form choline from ethanolamine, which is required for synthesis of phosphoglycerides and sphingomyelin which are required for formation of myelin and cell membranes. Hence, the neuropathy results from a... 

Structural formula A is typical of a group of compounds commonly called phosphoglycerides. In this particular depiction the symbols R1 and R2 are long-chain carboxylic acids linked in an ester linkage to the primary and secondary alcohol residues of glycerol. The symbol X is a mixed venue with a wide variety of bases—for example, choline (HOCH2CH2 N (CH3)3) or... 

The nomenclature rules just cited for phosphatidylcholine and its analogs also hold for ethanolamine phosphoglycerides. Mixtures of the diacyl, alkenyl acyl, and alkyl ether forms are found, for example, in macrophages and neutrophils but in much different ratios than observed for the choline-containing types (Figure 1-11). Again, only the (diacyl) phosphatidylethanol-amine is found in liver cells. These structures will be discussed in more detail in Chapter 5. 

The proof of structure on the naturally occurring phosphoglycerides is by no means a simple task, but it can be done with perseverance. Perhaps the best way to initiate such experiments is to explore in order the topics briefly discussed in the section entitled The Ubiquitous One (Diacyl)Phosphatidyl-choline. These are the essential components of a structure proof for these compounds. 

As mentioned in Chapter 2, the alkylacylcholine phosphoglycerides predominate in the choline-containing fraction in the majority of mammalian cells. On the other hand, the alkenylacyl form predominates in the ethanolamine-containing fraction. It is important to stress that these ether-linked lipids are found essentially only in the choline- and ethanolamine-containing phospho-glyceride. The reason for this high specificity of distribution is not known at present. 

A Common Physical-Chemical Feature of Non-Choline Containing Phosphoglycerides... 

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