Monosaccharides residue number

Carbohydrates are major constiments of animal food and animal tissues. They are characterized by the type and number of monosaccharide residues in their molecules. 

A number of complicated polymers having chains composed of monosaccharide residues are present at the surface of bacterial cells.1"4 These polymers often serve as characteristic antigens of bacteria, and are very diverse in their structure. They may be divided into three main groups ... 

The currently known structures of bacterial polysaccharides may be separated into several, biosynthetic types according to the nature of the activated forms of the monosaccharide residues in the main chain (for example, the UGT type means that UDP-, GDP-, and dTDP-activated sugars are present in the main chain). Table VIII shows the total number... 

The following numbers of monosaccharide residues per molecule were reported by Ott a-diainylose, 22 a-tetraamylose, 12 a-octaamylose, 63 /3-triamylose or /3-hexaamylose, 6 cellulose, 3 licheiiin, 7 starch, 2 and inulin, 6. The x-ray powder patterns published by Ott appear weak and poorly resolved, lending an additional item of doubt to an already tenuous argument. Herzog examined several known substances by Ott s method out of seven cases, only one was reasonably close to the correct value while the others were off by 40 to 500 %. 

Polysaccharides are macromolecules, containing a large number of monosaccharide residues. Their solubility in water is very low and they have no taste. Starch, cellulose, inulin and dextran are typical polysaccharides. 

On the other hand, the sugar moiety of the glycosphingolipids represents the hydrophilic part of the molecule. The solubility in water is also dependent on the number of monosaccharide residues bound in the molecule. Furthermore, such strongly anionic components as neuraminic acids, and sulfate or phosphate groups, influence the ratio of the solubility in water and fat. These two kinds of solubility characteristics are probably essential in the biological roles of the glycosphingolipids when they function as biomembrane components. 

A system already used (GL-5.3) is based on the abbreviated root names of the oligosaccharide structures. The full root structures are telrasaccha-rides. and sequential removal of terminal monosaccharide residues gives smaller, precisely defined structures. Elongation of root tetrasaccharidcs is, on the other hand, undefined and hence ambiguous. The root name may be used, followed by an arabic number indicating the total number of monosaccharide residues. A lowercase letter can be added to differentiate between particular compounds. 

Polysaccharides - Compounds consisting of a large number of monosaccharides linked glycosidicaUy. This term is commonly used only for those containing more than ten monosaccharide residues. Also called glycans. [5]... 

Figure 1.47 Simplified description of right-hand (a) and left-hand (b) polysaccharide helices where h is the length of each monosaccharide residue projected on the helix axis, and n is the number of residues per turn. A negative value implies left-hand and a positive value implies right hand. Spheres represent 0-glycosidic links between monosaccharide residues.

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