Glycerolipids biosynthesis

Vance DE Glycerolipid biosynthesis in eukaryotes. In Biochem-istry of Lipids, Lipoproteins and Membranes. Vance DE, Vance JE (editors). Elsevier, 1996. 

Hajra, A. K. Glycerolipid biosynthesis in peroxisomes (microbodies). Prog. Lipid Res. 34 343-364,1995. 

Agranofl, B. W., Hajra, A. K. The acyl dihydroxyacetone phosphate pathway for glycerolipid biosynthesis in mouse liver and Ehrlich ascites tumor cells. Proc. Natl. Acad. Sci. U.S. 68, 411-415 (1971). 

Peroxisome proliferators are also involved in two other metabolic pathways of importance to lipid metabolism. Peroxisomes contain the most of di-hydroxyacetone phosphate acetyltransferase and alkyldihydroxyacetone phosphate synthetase activities. Therefore, they are responsible for initiating most ether glycerolipid biosynthesis. These enzymes are also moderately induced by peroxisome proliferators. Induction of cytochrome P450s by peroxisome proliferators will be addressed separately. 

In plants, glycerolipid biosynthesis involves a complex web of reactions distributed among multiple compartments [11,12]. As in mammals (Chapters 8 and 10), the synthesis of individual glycerolipids is initiated either by the formation of CDP-diacylglycerol from phosphatidic acid and CTP, or by cleavage of phosphate from phosphatidic acid to produce diacylglycerol. 

In an attempt to examine some properties of cancer cells we have measured the ability of Novikoff hepatoma to take up the saturated and "essential fatty acids" from the host and the capacity of this tumoral tissue to distribute these acids between the different lipid fractions. pH -glycerol was also used as a marker for "de novo" glycerolipid biosynthesis. 

The low incorporation of [%[-glycerol into tumoral lipids would indicate a decrease of the glycerophosphate pathway for the glycerolipid biosynthesis. Nevertheless a lack in the glycerol activation to sn-glycerol-3-phosphate by the tumdral tissue cannot be ruled out. 

In order to study the processes of plant fatty acid desaturation and glycerolipid biosynthesis and to develop a crop seed oil with reduced level of saturated fatty acids, a rat liver stearyl-CoA A-9 desaturase (D9DS) gene was introduced into Nicotiana tahacum under the control of the 35S promoter via Agrobacterium transformation (3) and soybean somatic embryos with the seed-specific phaseolin promoter by particle bombardment. In this article, we decribe the effects of the mammalian A-9 desaturase on fatty acid composition of membrane and storage lipids. 

Kleppinger-Sparace, K., Stahl, R.J. and Sparace, S.A. (1992) Energy requirements for fatty acid and glycerolipid biosynthesis from acetate by isolated pea root plastids. Plant Physiol. 98, 723-727. 

Fatty acids in many leaves are desaturated in conjunction with phospholipids before incorporation into galactolipid (the cytosolic pathway). In 16 3-plants, the situation is further complicated by the presence of a chloroplastic pathway in addition to the cytosolic pathway of glycerolipid biosynthesis and fatty acid desaturation. 

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