Lipids formation

Elbert R, Laschewsky A and Ringsdorf H 1985 Hydrophilic spacer groups in polymerizable lipids— formation of biomembrane models from bulk polymerized lipids J. Am. Ohem. Soc. 107 4134-41... 

Fusarium moniliforme sya verticillioides causes the so-called ear rot disease in maize and produces fumonisin B, (IB,), one of the most frequently detected mycotoxins in the food supply chain worldwide (Steyn, 1995). FBi can inhibit lipid formation, particularly in the liver. Fumonisins have been detected and investigated only relatively recently. Several structurally related forms of fumonisins (FBS) have been associated with human cancer (e.g. FB with oesophageal cancer) as well as with a host of problems in livestock fed with FB -contaminated feed (D Mello, 2003 Benbrook, 2005). 

Rushdi, A. I. and Simoneit, B. R. (2001). Lipid formation by aqueous Fischer-Tropf-type synthesis over a temperature range 100 to 400 °C. Orig. Life Evol. Biosph., 31, 103-18. 

J Kato, S Fujisaki, K Nakajima, Y Nishimura, M Sato, A Nakano. The Escherichia coli homologue of yeast RER2, a key enzyme of dolichol synthesis is essential for carrier lipid formation in bacterial cell wall synthesis. J Bacteriol 181 2733-2738, 1999. 

Certik, M., Balteszova, L., and Sajbidor, J. 1997. Lipid formation and y-linolenic acid production by Mucorales fungi grown on sunflower oil. Lett. Appl. Microbiol., 25, 101-105. 

A versatile lipid formation leading to phosphatidic acid, diglycosyl-1,2-diacylglycerol, phosphatidylethanolamine, phosphaditylglycerol and cardiolipin... 

The structural unit of the phosphoglycerides is D-glycerol-3-phosphate, a derivative of the trivalent alcohol glycerol. The compounds glycerol and di-hydroxy-acetone were detectable in the Murchison meteorite. This does seem noteworthy as these biogenic compounds are not in the products of the prebiotic soup. What is the mechanism of lipid formation in meteorites This question has not been answered. 

The isomer trends of the models were very useful for helping the identification of isomers. Cell cultures of human leukemia cell lines (THP-1) were incubated in the absence and presence of thiol compounds, ensuring that no trans compounds could come from the medium [45]. In parallel experiments, some millimolar levels of thiol compounds were added to the cell cultures during incubation, and the comparison of isomeric trends was carried out. A basic content of trans lipids in THP-1 cell membranes could be found during their growth without thiol, and after the addition of the amphiphilic 2-mercaptoethanol, it increased to 5.6% of the main fatty acid residues. Moreover, when a radical stress by y-irradiation is artificially produced in the cell cultures added with thiol, a larger isomerization effect could be seen, with trans lipid formation up to 15.5% in membrane phospholipids. The fatty acid residues most involved in this transformation were arachidonate moieties, as expected. 

Acyl carrier protein, fatty acid synthase sequence, 45-46 Acyl carrier protein derivatives, desaturation, 13,l4f Acyl lipids, formation, 47-48 Aglycone skeletons saponins, 288f Solanum glycoalkaloids, 288f... 

Modeling of an exact stoichiometric distribution of different intracellular fluxes with the aim to understand and optimize intracellular product formation is indeed a field where much more work could be done. Stoichiometry can be shifted in one direction as the lipid formation example shows. In most cases it is not known how far the shift can go and to what extent it affects the costs for growth and productivity. 

The nervous system has proven useful for the study of another timely problem that of intracellular distribution of enzymes and substrates of structural lipid formation and degradation in eukaryotic cells and the mechanisms of their assembly into membranes. The neuron constitutes a particularly useful model, by virtue of its peculiar shape. Because its axon may be larger than the perikaryon by several magnitudes, we can take advantage of the process of axonal flow to study the rate of appearance of labeled lipid at some distance from sites of synthesis. 

Acetyl-CoA carboxylase is recognised generally as being a key enzyme in acyl lipid formation. In plants it has been shown to be important as a regulatory enzyme in light-driven lipid synthesis [1] and has a high flux control coefficient under such conditions [2]. Recently, characterisation of different isoforms of acetyl-CoA carboxylase from plants has been made. In Poaceae such as maize there are two multifunctional proteins [3]. By contrast, the dicotyledon pea contains a multienzyme complex form of acetyl-CoA carboxylase in the mesophyll chloroplasts but a multifunctional protein Isoform In the cytosol of epidermal cells [4]. 

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... 

S.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). 

Kendrick, A. and Ratledge, C. (1992a) Lipid formation in the oleaginous mould Entomoph-thora exitalis grown in continuous culture effects of growth rate, temperature and dissolved oxygen tension on polyunsaturated fatty adds. Appl. Microbiol. Biotechnol. yj, 18-22. 

Rushdi Al, Simoneit BR (2001) Lipid formation by aqueous Fischer-Tropsch-type synthesis over a temperature range of 100 to 400 degrees C. Grig Life Evol Biosph 31 103-118. doi 10.1023/A 1006702503954... 

Thus, the FA composition of sea buckthorn fruit reserve lipids is rather unusual. Firstly, the mesocarp contains a highly saturated oil such oils are present in few plant species /7,8/. Secondly, TAGs rich in C g-UFAs accumulate in the seeds although the latter are devoid of chloroplasts which are generally believed to be responsible for UFA synthesis in oilseeds (linseed, soybean etc. /9/). Therefore, the study of fruit reserve lipid formation in sea buckthorn, as a representative of POM, is desirable. To begin this study, we determined the dynamics of biomass and lipid accumulation in 12-105 DAF fruits (Fig. 1). It is seen that its rate is maximal at 50-78 (seeds) and 78-88 DAF (mesocarp) the absolute rate in mesocarp is higher than in the seeds by an order of magnitude, but the... 

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