Diacylglycerols derivatives

The main advantage of fluorescent derivatives is that they may be quantified down to the femto-mole level. Takamura and Kito separated anthroyl-diacylglycerol derivatives of PL molecular species by A/2-P (70/30) (90). 

CTP phosphatidate cytidylyltransferase has been observed in plastids, mitochondria, and ER. In all three compartments, the CDP-diacylglycerol derived from phosphatidic acid is used in the synthesis of phosphatidylglycerol in mitochondria, the reaction of phosphatidylglycerol with a second CDP-diacylglycerol then produces cardiolipin. The ER can also incorporate CDP-diacylglycerol into phosphatidylinositol and phosphatidylserine. 

Valeur, Michelsen and Odham (1993) showed how diacylglycerol- and monoacylglycerol-derived fragments of phospholipids were obtained. PG and PE were found in a phospholipid extract from bacterial cells Pseudomonas fluorescens). They achieved class separation of the phospholipids but did not apparently separate molecular species (Fig. 9.6). Collision-induced dissociation (CID)-MS-MS analyses of PI from soybean were performed which revealed specific fatty acid compositions of the selected diacylglycerol-derived fragment. 

Takagi, T. Suzuki, T. Effect of temperature on chiral and achiral separations of diacylglycerol derivatives by high-performance liquid chromatography on a chiral stationary phase. J. Chromatogr. A, 1992, 625, 163-168. 

Resyttthesis of Triacylglycerols from Diacylglycerols Derived from... 

Diacylglycerol derived from the hydrolysis of phosphoinositides by phosphoinositide-specific phospholipase C... 

One novel procedure that may repay attention consisted in selectively deuterating the double bonds in the fatty acids of diacylglycerols derived from phospholipids, prior to conversion to the BDMS ether derivatives for GC separation as above [219]. In this instance, mass spectrometry served to identify and quantify unresolved components in specific peaks. 

As the molecular weights of diacylglycerol derivatives are much lower than those of triacylglycerols, there appears to be no difficulties with quantification and uncorrected detector responses should give comparable results to those obtained by other means. 

Figure 8.17. High-temperature GC of derivatized plasma lipids on a WCOT column (8 m x 0.3 mm) of fused silica, coated with SE-54, and temperature-programmed to a maximum of 340 C [647]. Abbreviations A, TMS ester derivatives of free acids B, TMS ethers of monoacylglycerols (derived from lysophosphatidylcholine) C, TMS ether of cholesterol D, tridecanoin (internal standard) E, TMS ether of 16 0-sphingosine (derived from sphingomyelin) F, TMS ethers of diacylglycerols (derived from phosphatidylcholine) and ceramides G, more TMS ethers of ceramides H, cholesterol esters J, triacylglycerols. (Reproduced by kind permission of the authors and of the Journal of Biochemical and Biophysical Methods, and redrawn from the original paper).

Laakso, P and Christie, WW (1990) Chromatographic resolution of chiral diacylglycerol derivatives potential in the stereospecific analysis of triacyl-jw-glycerols. Lipids, 25,... 

Kennedy also demonstrated the central role of phosphatidic acid in both phospholipid (section 7.1.2) and triacylglycerol biosynthesis and one of his outstanding contributions has been to point out that the diacylglycerol derived from phosphatidic acid forms the basic building block for triacyl-glycerols as well as phosphoglycerides. 

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