Cerebrosides glycolipid structure

Biochemistry and molecular biology of structural components. The schistosome tegument contains several phospholipids, the most abundant being phosphatidylcholine (57%), phosphatidylethanolamine (17%), sphingomyelin, lysophosphatidylcholine, phosphatidylinositol and cerebroside glycolipids (7,34). Palmitic acid and oleic acid are the most abundant fatty acids (35). These molecules are derived from the host, as schistosomes are unable to synthesize cholesterol or long-chain fatty acids de novo (36). However, schistosomes can interconvert fatty acids and cleave the polar head from some phospholipids (37). 

From the sponge M. incrustans, two cerebrosides and a polar glycolipid were isolated.78 Both cerebrosides contain galactose and sphingosine, but differ in the nature of their fatty acids the less polar cerebroside contains normal, and the more polar, monohydroxy, acids. The structure of the polar glycolipid was not established, but it was shown to contain sphingosine, fatty acids, galactose, arabinose, fucose, and phosphorus.78... 

Other glycolipids from aquatic invertebrates are also characterized by a great variety of structures. Along with compounds known also to be present in vertebrates (gluco- and galacto-cerebrosides and lactosylceramide), new glycosphingolipids have been detected that differ from the glycosphin-... 

Formation of membrane structures is also due to the hydrophobic effect. When a molecule is composed of both polar and nonpolar moieties, it is said to be amphiphilic. Since the hydrophobic effect is concerned with the tendency for nonpolar molecules or nonpolar components of molecules to associate spontaneously in aqueous solutions, there is a wide range of small molecules such as fatty acids and phospho- and glycolipids which, when dissolved in water, segregate to form membranes or micelles [146]. The same type of segregation occurs in the crystalline state, as in the structures of the long chain alkyl glycosides [147], cerebrosides,... 

Glycosphingolipids, or glycolipids, include the cerebrosides, sulfatides, and gan-gliosides and are built on a ceramide backbone structure, which is a fatty acid amide derivative of sphingosine ... 

Both the reduced periodate-oxidized cerebroside and the ceramide were as active as the original cerebroside, suggesting that the sugar moiety is not important for activity. The sphingoid moiety of a cerebroside constitute an essential part of the activity and the fatty acid having a certain chain length and the 2-hydroxy fatty acids may be the functional structures of this glycolipid (80). 

Fig. 30.15. Structures of cerebrosides and gangliosides. In these glycolipids, sugars are attached to ceramide (shown below the glycolipids). The boxed portion of ceramide is sphin-...

Glycolipids are another type of sphingolipid. Unlike sphingomyelins, however, these complex lipids contain carbohydrates (usually monosaccharides such as glucose or galactose). Glycolipids are often called cerebrosides because of their abundance in brain tissue. The structure of a typical cerebroside is... 

Biochemistry of organ glycolipids. III. The structures of human kidney cerebroside sulfuric ester, ceramide dihexoside and ceramide trihexoside. J. Biochem. (Tokyo) 66,365 (1964). 

Sphingoplasmalogens, a new class of glycolipids recently described by Kochetkov et al. (1963, 1964), contains a vinyl ether (at carbon 3 of the sphingosine) in a cerebroside structure ... 

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