L-a-phosphatidyl ethanolamine

L-a-Phosphatidyl ethanolamine (cephalin) phospholipid commonly C7Hj2NOgP(2R) found in microorganisms, but largely absent in plants. 

Abbreviations EPR, electron paramagnetic resonance FITC, fluorescein-5 -isothiocyanate lAEDANS, iV-iodoacetyl-N -(5-sulfo-l-naphthyl)ethylenediamine NCD, fluorescent yV-cyclohexyl-N -(4-dimethyl-amino-a-naphthyl)carbodiimide RITC, rhodamine-5 -isothiocyanate DPPE, dipalmitoylphosphatidyl-ethanolamine PE, egg phosphatidyl-ethanolamine ANS, 8-anilino-l-naphthalene sulfonate DPH, diphenylhexatriene e-ADP, l,iV -ethanoadenosine-5 -diphosphate TNP-ADP, 2 [3 ]-0-(2,4,6-trinitrophe-nyl)adenosine-5 -diphosphate. 

Dillard, C. J., and A. L. Tappel. Fluorescent products from reaction of peroxidiz-ing polyunsaturated fatty acids with phosphatidyl ethanolamine and phenylalanine. Upids 8 183-189, 1973. 

Also, the primary amine moities of polar lipids catalyze the aldol condensation of Cm-Cig aldehydes resulting from plasmalogen hydrolysis, thus forming a,3-unsaturated aldehydes (l2t). Phosphatidyl ethanolamine reacted with propanal and n-hexanal forming phosphatidyl l-(2-hydroxyethyl)-2-ethyl-3,5-dimethyl pyridinium, and phosphatidyl-1-(2-hydroxy ethyl)-2-hexyl-3,5-dipentyl pyridinium, respectively (125). The peridinium ring is formed by the reaction between one mole of amino-N of phosphatidyl ethanolamine and three moles of n-alkanals. The same reaction took place in the synthesis of substituted pyridines by condensation of carbonyl compounds with ammonia (126, 127). 

As shown in Table 1, the acyl moiety of cardiolipin is comprised almost entirely of unsaturated fatty acids. Other membrane phospholipids such as phosphatidyl choline and phosphatidyl ethanolamine contain 10-40 mol of saturatedfatty acids such as palmitic acid (Cl6 0) and stearic acid (Cl8 0) per 100 mol of total fatty acids. In particular,linoleic acid (Ci8 2) is the most abundant polyunsaturated fatty acid consisting of 80 mol%, linolenic acid (Ci8 3) 8 mol%, and oleic acid (Cl8 l) 6 mol%. Therefore, by using a commercially available cardiolipin purified from bovine heart mitochondria, we characterized auto-oxidation products by reverse phase HPTLC and reverse phase HPLC. 

The phospholipid monolayers examined in this study were all saturated, symmetric, l,2-diacyl-j -glycero-3-phosphate-based lipids. Four different lipid headgroups attached to the phosphate were examined choline, ethanolamine, glycerol and serine. Each lipid features a glycerol backbone, two saturated fatty acid chains and a phosphatidyl headgroup. 

The effect of cholesterol on lateral diffusion has also been studied. Rubenstein and co-workers [50] have found that the lateral diffusion of a fluorescent labelled phosphoUpid, phosphatidyl-iV-(4-nitrobenzo-2-oxa-l, 3-diazole)ethanolamine, exhibited an abrupt change in its lateral diffusion coefficient at 20 mole% cholesterol in a binary mixture of cholesterol and dimyristoylglycerophosphochoUne. Two explanations for this behaviour have been proposed based on the existence of ordered microscopic domains characterised by ripples or strips of solid phase interspread with the more fluid domains of the phosphoUpid-cholesterol complex [51-53]. Such a structure would form barriers to free lateral diffusion. An alternative... 

Fig. 21.2 Negative ion MALDI-TOF mass spectra of l-palmitoyl-2-oleoyl-sn-phosphatidyl-ethanolamine (a), l-palmitoyl-2-oleoyl-sn-phosphatidylserine (b) and 1,2-dipalmitoyl-sn-phosphatidylinositol-3-phosphate (c). In all cases a 0.5 M solution of DHB in methanol was used as matrix and the sample solutions (0.5 mg/ml) diluted 1 1 (v/v) with the matrix. All peaks are marked according to their m/z ratio and DHB matrix peaks are marked with asterisks. Please note the considerable intensity of the cluster ions between DHB and the different analytes. Please also note that the contribution of matrix peaks is much higher than in the positive ion spectra...

The total lasalocid-membrane binding reaction is a very sensitive fimction of the membrane polar head group composition Incorporation of dimyristoyl phosphati-dic acid (DMPA) or dimyristoyl phosphatidyl ethanolamine (DMPE) into pure DMPC vesicles reduces the total lasalocid fluorescence relative to that observed in pure DMPC vesicles. Fluorescence lifetime experiments indicate the decrease in fluorescence is not due to reduction of the quantum yield of the bound lasalocid but rather to a reduction in the degree of binding. The sensitivity of total ionophore binding to polar head group composition is similar to that observed for the fluorescent spin probe l-anilino-8-naphthalenesulfonate and indicates... 

The calculation of selectivity values showed that there was discrimination against the incorporation of the deuterated CLA isomers into TAG and CE and a preferential incorporation into PC and phosphatidyl ethanolamine (PE) relative to 9-18 1- /8 and 9, l2-18 2- Q. Comparison of selectivity values for the CLA isomers to r9, l2-18 2- 2 values and values previously reported for c- and r-18 1 positional isomers and 18 0 (17-22) showed that the incorporation of cS,t - and rlO,rl2-CLA matches the r-18 l isomers more than 18 0, 9-18 1, or 9, 12-18 2. This observation is an interesting anomaly since several positive health benefits have been reported for CLA (4), but tram fatty acids (TEA) are considered to have a negative effect on serum cholesterol. Epidemiological studies found a relationship between coronary heart disease risk and dietary intake of TEA from partially hydrated vegetable oils, which mainly contain the t9-, rlO-, and rl 1-18 1 isomers, but no such relationship was found for TEA intake from animal derived foods, whose major TEA isomer is t9-18 1 (vaccenic acid, VA) (19,23,24). 

Fig. 3. Lipid exchange between potato subcellular fraction in vitro, (a), (c), and (e) Incubation of radioactive lipid-labeled microsomes with unlabeled mitochondria, (b), (d), and (f) incubation of radioactive lipid labeled mitochondria with unlabeled microsomes. Incubation periods are plotted on the abscissa the quantities of each phospholipid class transferred to the receiver fraction after different incubation periods are plotted on the ordinate. In (a) and (b) the lipids of the donor fraction were labeled in vivo from [l- K2]acetate, in (c) and (d) from [ P]phosphate, and in (e) and (f) from [l- C]glycerol. Triangles, phosphatidylcholine open stars, phosphatidyl-ethanolamine solid stars, phosphatidylinositol solid circles, phosphatidylglycerol open circles, diphosphatidylglycerol squares, phosphatidylserine (from Ben Abdelkader and Mazliak, 1970).

Ethanolamine, amimoethaaok H2N-CH2 H2-OH, a biogenic amine produced by decarboxylation of L-serine. It is a common constituent of phospholipids in which it is esterified to an acylglycerol phosphate moiety to form phosphatidyl ethanolamine (see One-carbon cycle). 

PBLG), and poly(N-hexyl stearate L-aspartamide), and non-biodegradable hydrophobic polymers like poly(propylene oxide) (PPO) and poly(vinyl) derivatives. The hydrophobic segment can be inert or can possess reactive groups for postfunctionalization. A special group of micelles can finally be obtained from lipid conjugates such as PEG-phosphatidyl ethanolamine (PEG-PE). ... 

Cells grown for 2 days with Swim s medium and calf serum were incubated with l-14c linoleic acid for 24 h in a new Swim s medium without serum. Means of three bottles 1 SEM. Total fatty acids (TFA), phosphatidyl choline (PC), phosphatidyl ethanolamine (PE), free acids (FA) and neutral lipids (NL) fractions. 

Figure 10.6 Calibration curves for 50-2500 ng of phosphatidyl ethanolamine (EA), lecithin (L), and sphingomyelin (S). Standards were developed on preadsorbent silica gel plates with ethyl acetate-n-propanol-chloroform-meth-anol-0.25% aqueous KCI (25 25 25 13 9) and scanned in the single-beam transmission mode with a Kontes densitometer after detection by charring. [Reproduced with permission of Wiley-Interscience from Zelop et al. (1985).]...

Obtain the following phospholipid standards from Matreya a polar lipid standard containing equal amounts of lysophosphatidylcholine, phosphatidylcholine, phosphatidyl ethanolamine, and cholesterol a sphingomyelin standard containing equal amounts of sphingomyelin, sulfatides, and three cerebrosides individual phosphatidyl inositol and phosphatidyl serine standards. Each standard is supplied in 25-mg amounts dissolved in 1 ml of chloroform-methanol (2 1). Add 4 ml of chloroform-methanol (2 1) to each standard to achieve a final concentration of 5 J.g/ J-l. 

Reference has been made already to the recent findings of Kanfer and Kennedy (1964), who showed that in cell-free extracts of E, coli phosphatidyl serine is formed by a different pathway. A phosphatidyl group is transferred from CDP-diglyceride to L-serine by a highly specific enzyme L-serine-CMP phosphatidyl-transferase (Reaction 21). In this organism most of the phosphatidyl serine so formed is decarboxylated to yield phosphatidyl ethanolamine (Reaction 22). 

Phosphatidyl Serines are widely distributed and were initially isolated from the cephahn fraction of brain (Folch 1948). Its positive ninhydrin reaction is due to L-serine. As compared to phosphatidyl choline and -ethanolamine, phosphatidyl serine represents a minor component of the glycerophosphoUpid mixture and generally occurs as the K+-salt, other ions being Na+, Mg++ and Ca++. Its function in cation metabolism of erythrocytes has been discussed. 

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