Glycolipids and

Another simple sugar that enters glycolysis at the same point as fructose is mannose, which occurs in many glycoproteins, glycolipids, and polysaccharides (Chapter 7). Mannose is also phosphorylated from ATP by hexokinase, and the mannose-6-phosphate thus produced is converted to fructose-6-phosphate by phosphomannoisomerase. 

Phospholipids are a major component of all biological membranes together with glycolipids and cholesterol. Due to their polar nature, i.e. hydrophilic head and hydrophobic tail, phospholipids form in water vesicles or liposomes. 

The presence and biological importance of oligosaccharide structures, usually as components of glycolipids and glycoproteins, in bacterial capsular and cell-wall polysaccharides, in mammalian cell membranes, in cytoplasm, and in extracellular fluids, are now well documented. They are important constituents in... 

D-Galactose Hydrolysis of lactose. Can be changed to glucose in the liver and metabolized. Synthesized in the mammary gland to make the lactose of milk. A constituent of glycolipids and glycoproteins. Failure to metabolize leads to galactosemia and cataract. 

Some alcohols, arylamines, and phenols are sulfated. The sulfate donor in these and other biologic sulfation reactions (eg, sulfation of steroids, glycosaminoglycans, glycolipids, and glycoproteins) is adenosine 3 -phos-phate-S -phosphosulfate (PAPS) (Chapter 24) this compound is called active sulfate. ... 

Biological membranes consist of lipids, proteins and also sugars, sometimes mutually bonded in the form of lipoproteins, glycolipids and glycoproteins. They are highly hydrated—water forms up to 25 per cent of the dry weight of the membrane. The content of the various protein and lipid components varies with the type of biological membrane. Thus, in... 

The low molecular weight mJz region of spectra derived from microorganism whole cells is generally comprised of mass spectral peaks derived from glycerides, phospholipids, glycolipids, and small protein fragments. This mass spectral information should be examined as a compliment to protein bio-... 

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

Compound lipids (phospholipids, sphingolipids, glycolipids, and cholesterol and its esters) that make part of the biomembrane are subject to a less active renew-al as compared with triacylglycerides. Their renewal is associated either with the restoration of an impaired portion of the membrane, or with the replacement of a defective molecule by a new one. 

Lipoteichoic acid (LTA), which is a characteristic and widespread cell-surface constituent of gram-positive bacteria, is an amphiphile consisting of two covalently-bound distinct parts, i.e., a glycolipid and a hydrophilic poly(glycerol phosphate). 

Methylation analysis (and its different applications) is one of the most widely used methods in the structural characterization of carbohydrate chains (reviewed in refs, 5-8). In the present article, the progress achieved, and the problems encountered, in the analysis of animal glycolipids and glycoproteins are discussed, although many of the topics also concern the analysis of carbohydrate chains in general. Emphasis is laid on the efforts made to find ways to lessen the amounts of sample needed for the analysis, because only small amounts of glycan samples isolated from biological sources are often available. 

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