Glycerolipid synthesis

1 Fatty acyl-CoA synthetase. Cytosolic processing of fatty acid and lipid formation is a highly integrated process. An active acyl-CoA pool exists and is dependent upon a supply of fatty acid from the plastid. The composition of this pool can be analyzed by capillary electrophoresis (MacKenzie and Taylor, 1990). Formation of acyl-CoAs involves fatty acyl-CoA synthetase (EC 6.2.1.3) and appears to occur on the inner face of the plastidic envelope. While a broad specificity for fatty acids exists in various oilseeds, a preference is shown for medium-chain fatty acids in Cuphea and for very-long-chain fatty acids in Crambe (Battey and 

Ohlrogge, 1989). Thus a definite plant specificity appears to exist and is responsible, in part at least, for the characteristic oil production seen in specific oilseeds. 

2 Fatty acyl-CoA transferases. The enzyme systems involved with fatty acyl-CoA utilization in the cytosol appear to be membrane-bound. Consequently, detailed knowledge of their individual structure, specificity and genetic control is generally lacking due to the particular inability to obtain ready isolation and purification of the relevant proteins. Studies, however, support the concept of the operation of the eukaryotic pathway for the production of glycerolipids and polyunsaturated fatty acid (Browse et al., 1990 Stymne et al., 1990). While this pathway may contribute a significant quantity of fatty acid for use in membrane synthesis in the plastid (chloroplast) (Browse et al., 1990), its major importance would seem to lie with the production of unsaturated oils (Frentzen, 1986). On the other hand the occurrence of the prokaryotic pathway in the plastid permits more direct membrane lipid formation in both 16 3 and 18 3 plants (Browse et al., 1990 Somerville and Browse, 1991). Different sets of acyltransferase may be associated with the two pathways (Hills and Murphy, 1991). 

Immunological methods have been employed in an attempt to establish 

A specialized LPAAT capable of introducing ricinoleic acid at position 2 of oleoyl-LPA appears to exist in castor bean (Stymne et al., 1990). Environmental factors such as temperature can also influence enzymic affinity for substrates in maturing safflower seeds (Ichihara et al., 1987). 

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Santiago, T. C., Zufferey, R., Mehra, R. S., Coleman, R. A., and Mamoun, C. B. (2004). The Plasmodium falciparum PfGATP is an endoplasmic reticulum membrane protein important for the initial step of malarial glycerolipid synthesis. /. Biol. Chem. 279,9222-9232. 

Browse, J. and C. Somerville, Glycerolipid synthesis Biochemistry and regulation, Annu. Rev. Plant Physiol. Plant Mol. Biol., 42, 467-506 (1991). 

Table 1, Changes in glycerolipid synthesis from C glycerol due...

An active glycerolipid synthesis from C-glycerol, predominantly phosphatidylinositol formation, takes place in the toad retina both in vivo and in vitro (Bazan Bazan, 1976). To further study this process a survey of different incubating conditions was carried out. These included variations in temperature, the use of different ionic environments, and the action of a divalent ionophore. In addition it was of particular interest to inquire about the effect of the physiological stimulus of the retina, the light, on the de novo biosynthesis of lipids from C-glycerol in the entire toad retina. 

ACBP) can mediate intermembrane acyl-CoA transport and donate acyl-CoA for -oxidation and glycerolipid synthesis, /. 299 165-170... 

Mukherjee, K.D. (1986) Glycerolipid synthesis by homogenate and oil bodies from developing mustard (Sinapis alba L.) seed. Planta 167, 279-283. 

GLYCEROLIPID SYNTHESIS IN MICROSOMES AND OIL BODIES OF OIL PALM MESOCARP... 

Ohnishi J.I. and yamada M. (1980) Glycerolipid synthesis in Avena leaves during greening of etiolated seedlings 111. 

Acyl-(acyl-carrier protein) glycerol-3-phosphate acyl transferase (glycero-P acyltransferasc) in higher-plant chloroplasts transfers the acyl group from acyl-(acyl-carrier protein) to the C-1 position of glycerol 3-phosphate to synthesize 1-acylglycerol 3-phosphate. Since this reaction is the first step of glycerolipid synthesis in the chloroplasts, it is of special interest to study this enzyme. 

Roughan PG, CR Slack (1984) Glycerolipid synthesis in leaves. TIBS 9 383-386... 

G. Roughan and R. Slack, Glycerolipid synthesis in leaves. Trends Biol. Sci. 9 383... 

The activities of glycerol-3-phosphate acyltransferase and 1-acyl-glycerol-3-phosphate acyItransferase, the enzymes involved in the first steps of glycerolipid synthesis, have been characterized in crude extracts of Andbaena variabilis (Lem and Stumpf, 1984b Stapleton and Jaworski, 1984a,b). These enzymes use acyl-carrier protein (AGP), but not coenzyme... 

Browse J, Somerville C. Glycerolipid synthesis biochemistry and regulation. Annu Rev Plant Physiol Plant Mol Biol 1991 42 467-506. 

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