Biosynthesis and its Control

Despite a lot of bad press, cholesterol remains an essential and important biomolecule in animals. As much as half of the membrane lipid in a cellular membrane is cholesterol, where it helps maintain constant fluidity and electrical properties. Cholesterol is especially prominent in membranes of the nervous system. 

Cholesterol also serves as a precursor to other important molecules. Bile acids aid in lipid absorption during digestion. Steroid hormones all derive from cholesterol, including the adrenal hormones that maintain fluid balance Vitamin D, which is an important regulator of calcium status and the male and female sex hormones. Although humans wouldn t survive in one sense or another without cholesterol metabolites, cholesterol brings with it some well-known side effects. Doctors find cholesterol derivatives, being essentially insoluble in water, in the deposits (plaque) that characterize diseased arteries. 

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Demain, A.L. and Vaishnav, P. (2006) Involvement of nitrogen-containing compounds in /3-lactam biosynthesis and its control. Critical Reviews in Biotechnology, 26, 67—82. 

Sedgwick, B., The control of fatty acid biosynthesis in plants, in Biosynthesis and its Control in Plants (B. V. Milborrow, ed.), 179-217, Academic Press, London, 1973. 

Briggs, D.E. Hormones and carbohydrate metabolism in germinating cereal grains. In Biosynthesis and Its Control in Plants. Milborrow, B.V. (ed.). London Academic Press, 1973, pp. 219-277... 

Cadas H, Gaillet S, Beltramo M, Venance L, Piomelli D. Biosynthesis of an endogenous cannabinoid precursor in neurons and its control by calcium and cAMP. J Neurosci 1996 16 3934-3942. 

Jeffcoat R. (1979) The biosynthesis of unsaturated fatty acids and its control in mammalian liver. Essays Biochem. 15, 1-36. 

Tomasi, V., Meringolo, C., Bartolini, G. and Orlandi, M. (1978). Biosynthesis of prostacyclin in rat liver endothelial cells and its control by prostaglandin E2. Nature (London), 273, 670-671... 

To further our understanding of lipid biosynthesis and its regulation in a major oil producing crop, we have generated Brassica napus plants containing antisense constructs to ACCase I. 6-Ketoacyl ACP reductase, is a central component of the fatty acid synthase complex, and in a complementary experiment we have also generated antisense plants to this. Each construct was placed under the control of both a constitutive CaMV 35S promoter and a seed specific promoter. 

London, I. M. (1965). The biosynthesis of hemoglobin and its control in relation to some hypochromic anemias in man. Series Haematol. 2,1—25. 

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