Glycan

Polysaccharides. Polysaccharides, also called glycans, are the nutrient and stmctural materials of plants. They are a principle part of the carbohydrate portion of the biomass. The most prevalent monomeric carbohydrate is glucose. Common polysaccharides are all polymers of glucose (Pig. 

The term represents the kinetic efficiency of the enzyme. Table 14.4 lists turnover numbers for some representative enzymes. Catalase has the highest turnover number known each molecule of this enzyme can degrade 40 million molecules of HgOg in one second At the other end of the scale, lysozyme requires 2 seconds to cleave a glycosidic bond in its glycan substrate. 

L-Fucosamine was found as a constituent of Pneumococcus Type V capsular polysaccharide and as a constituent of the mucopolysaccharides (glycosamino-glycans) of certain enteric bacteria A new synthesis was devised to make the amino sugar more available. 

The term glycan has also been used for the saccharide component of a glycoprotein, even though the chain length may not be large. 

A general term for a polysaccharide (glycan) composed of a single type of monosaccharide residue is obtained by replacing the ending -ose of the sugar name by -an . 

Note. When the linkage between monosaccharide units is non-glycosidic (as in the phosphate derivative shown below), use of the glycan terminology is inappropriate other methods of polymer nomenclature should be employed [20],... 

A polysaccharide (glycan) composed entirely of glycuronic acid residues is named byreplacing -icacid by -an . The generic name for this group of polysaccharides is glycuronan . 

When substitution occurs in a polysaccharide (glycan), each type of sub cited in the name at an appropriate position (in alphabetical order). 

Location of the Position of Attachment of a Glycan on the Polypeptide Backbone of a Glycoprotein... 

As part of a study on cell-surface glycans, 2,3-bis(tetradecyloxy)propyl 2-deoxy-2-fluoro-a- and - -D-mannopyranosides were prepared by condensation of 3,4,6-tri-0-benzyl-2-deoxy-2-fluoro-a-D-mannopyranosyl chloride with 2,3-bis(tetradecyloxy)propanol. 

Secretory proteins and proteins destined for membranes distal to the ER completely traverse the membrane bilayer and are discharged into the lumen of the ER. 7V-Glycan chains, if present, are added (Chapter 47) as these proteins traverse the irmer part of the ER membrane—a process called cotranslational glycosyla-tion. Subsequently, the proteins are found in the... 

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