Glycolipids table

Since pyruvated glucosyl donors appeared to be rather unreactive, problems were also expected for the efBcient construction of contiguously pyruvated oligosaccharide structures as found in the mycobacterial glycolipids (Table 1). Therefore, a novel glycosylation procedure based on the glycosylation of silylat-ed alcohols with glycosyl fluorides has been developed for the solution of this problem and is discussed here. 

It appears evident therefore that the main function of most nutrient elements is as a constituent of the enzymes required to build up the organic matter within plants. Many such reactions run side by side in cells and tissues, and this is made possible by the presence of biomembranes that allow the build-up and decomposition of compounds, without mixing the components. Biomembranes subdivide cells into reaction spaces (e.g., nucleus, plastids, mitochondria, ribosomes, vacuoles, cytosol), and they permit well-ordered substance exchange between the compartments. Such processes are also responsible for ion uptake by root cells from the soil solution. Despite certain differences, all biomembranes have a similar chemical structure, the basic components being double lamellae of P-containing lipids (Figure 2.2) such as phosphatidylserine and glycolipids (Table 2.4). Proteins are movably incorporated into these double lamellae (see... 

Table 10.2 Self-assemblies from the unsaturated glycolipids and their typical size and dimensions. Reprinted with permission from [76] (2005) American Chemical Society8. ...

Table I gives a compilation of the molecular composition of SFV grown in BHK-21 cells, based on the revised weight for the viral particle of 41-42 X 10 daltons (Jacrot et al, 1983). If one assumes that each phospholipid-cholesterol pair takes up a surface area of about 90-100 A (Israelachvili and Mitchell, 1975) and each glycolipid about 55 A (Pascher and Sundell, 1977), then about 80% of the surface area in the bilayer is occupied by the lipids, leaving about 20% for the spanning proteins. This is somewhat more than would be expected if 180 spike proteins span the bilayer, each having two transmembrane a helical segments.

The structure of one of the cytokine-inducing glycolipids, GL4, was then studied [18]. GL4 consisted of phosphate, mannose (Man), Glc, Gro, and FAs (Table 1). MALDI-TOF-MS showed several distinct peaks around... 

Table 1. Incorporation of several glycolipids (GS) into egg phosphatidyl choline (PC). Results obtained with H-labelled phospholipids and C-labelled glycolipids ...

Blix (8, 9, 10) after mild acid hydrolysis of bovine submaxillary glycoprotein isolated a crystalline material called sialic acid which gave the direct and indirect Ehrlich reactions. Table I shows that similar substances were isolated by other workers from glycolipids (11, 12), other... 

Most sialylations so far reported have been achieved with soluble transferases, and seldom on a more than 20-/imol scale (see Table IX), with the intention to prepare and describe sequences present in glycoproteins and glycolipids. Trisaccharide < -D-Neu5Ac-(2— 3)-/J-D-Galp-(l — 3)-/J-d-... 

Table I. Some Characteristics of Different Compartments of Rat Small Intestine. The Blood Group Activities Concern Glycolipid Fractions.

The glycolipids of the testis of a number of animals have been analysed to determine whether SGG is a universal constituent of testicular tissue of all chordates. The results of these studies are summarized in Table III. 

Two other points arising from this line of work also deserve brief discussion. Firstly, it is relevant to mention that sulfo-quinovosyl diglyceride has been reported to be the major glyco-lipid of the spermatozoa of sea urchins (58). It will thus be of interest to extend studies of the comparative biochemistry of testicular glycolipids to lower classes of animals as well as to further members of the classes listed in Table III. Secondly, it is apparent that, whatever the precise phylogenetic distribution of glycolipids in testis may turn out to be, the results to date strongly support the hypothesis that sulfatides play an important role in testicular and/or spermatozoal function in chordates. 

Extensive purification of the glycosphingolipids present in the neutral fraction resulted in the isolation of three distinct glycolipids exhibiting Forssman antigenic activity (Table I, compounds 9,10,11). Thin-layer chromatographs of these glycolipids is illustrated in Fig. 1. Chemical analyses of the purified... 

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