Dipalmitoyl phosphatidyl ethanolamine

Figure 6 Artist s view of lipid/protein interaction derived from the electron density model from XR measurements and available structural data. The lipid monolayer is dipalmitoyl phosphatidyl ethanolamine (DPPE) and the protein is a membrane surface layer protein from B. sphaericus (from ref. [28]). The structural model sketched was based [28, 29] on the electron density profile (black line) inverted from measured reflectivity data as described in the text.

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...

Recently, the competitive adsorption dynamics of phospholipid/protein mixed system at the chloroform/water interface was investigated by using the drop volume technique. The three proteins P-Lactoglobulin, P-Casein, and Human Serum Albumin were used in this study. To investigate the influence of the phospholipid structure at concentrations close to the CAC (critic aggregation concentration) the four lipids dipalmitoyl phosphatidyl choline (DPPC), dimyristoyl phosphatidyl choline (DMPC), dimyristoyl phosphatidyl ethanolamine (DMPE)... 

The DMPA (Sigma, Miinchen, West Germany) was chromatographically pure. As a fluorescent tracer, dipalmitoyl-nitrobenzoxadiazol-phosphatidyl-ethanolamine (DP-NBD-PE, Avanti, Birmingham, AL) was used in a concentration of 0.25 mol%. The lipid mixture was spread from a 3 1 chloroform/ methanol solution. 

Abrahamsson etal. (1978) have described two hydrid subcells in complex lipids. Thus a twinned version of the O i subcell, with dimensions a = 10.3 A, 6 = 7.5 A, c = 2.54 A, was observed in the crystal structure of a cholesteryl ester (Abrahamsson and Dahlen, 1977), in 1,2-dilauroyl-DL-phosphatidyl-ethanolamine (Hitchcock et al., 1974) and also in the corresponding dipalmitoyl analogue (Dorset, 1976). 

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