Carbohydrate component

The most important derivatives of pyrimidines and purines are nucleosides Nucleosides are N glycosides m which a pyrimidine or purine nitrogen is bonded to the anomeric carbon of a carbohydrate The nucleosides listed m Table 28 2 are the mam building blocks of nucleic acids In RNA the carbohydrate component is d ribofuranose m DNA It IS 2 deoxy d ribofuranose... 

Section 28 7 Nucleic acids are polynucleotides present m cells The carbohydrate component is D nbose m ribonucleic acid (RNA) and 2 deoxy d ribose m deoxyribonucleic acid (DNA)... 

Table 3. Yields of Carbohydrate Components from Loblolly Pine...

Pyruvate ketals add to the anionic nature of the exopolysaccharide and are usually present in stoichiometric ratios with the carbohydrate component Pyruvate is normally attached to the neutral hexoses but may also be attached to uronic adds. In the absence of uronic acids, pyruvate alone contributes to the anionic nature of the exopolysaccharide. 

The award of a Beit Memorial Fellowship for medical research in 1933 provided him with more financial security and independence. Stacey moved to London and for the next 3 years worked full-time in Raistrick s laboratory. He was given the task of working on vaccines against typhoid fever. The work was successful eventually and the vaccines were used by the Royal Air Force and also were sent to the Air Force in New Zealand. Also, some advances were made in studies of the carbohydrate components of the vaccines. In addition to this research, he completed, by part-time study, the diploma course in bacteriology. 

Carbohydrate Components of Antibiotics. Part II. Alkaline Degradation of Mycaminose and Synthesis of 3,6-Dideoxy-3-dimethylammo-L-altrose and Derivatives Therefrom, A. B. Foster, J. Lehmann, and M. Stacey, /. Chem. Soc., (1962) 1396-1401. 

The carbohydrate components of a glycoprotein range from 1% to more than 85% of its weight and may be simple or very complex in structure. 

R. A. Hamlen, F. L. Lukezic, and J. R. Bloom, Influence of age and stage of development on the neutral carbohydrate components in root exudates from alfalfa plants grown in a gnotobiotic environment, Canadian Journal of Plant Science 52 633 (1972). 

Robert C. Elderfield, The Carbohydrate Components of the Cardiac Glycosides. 147... 

Acid hydrolysis of hamameli-tannin readily causes liberation of the carbohydrate component, 2-(hydroxymethyl)-D-ribose, together with two molar proportions of gallic acid, which presumably occupy similar positions, since there is no difference in their rate of cleavage. Methylation of hamameli-tannin with diazomethane, and subsequent alkaline hydrolysis,... 

Most of the LPS biological activity (pyrogenicity) is associated with its lipid A moiety. This usually consists of six or more fatty acids attached directly to sugars such as glucosamine. Again, as is the case in relation to the carbohydrate component, lipid A moieties of LPS isolated from different bacteria can vary somewhat. The structure of E coli s lipid A has been studied in the greatest detail its exact structure has been elucidated and it can be chemically synthesized. 

Human IL-2 is a single-chain polypeptide containing 133 amino acids. It is a glycoprotein, the carbohydrate component being attached via an O-linked glycosidic bond to threonine... 

Human TNF-a is initially synthesized as a 233 amino acid polypeptide that is anchored in the plasma membrane by a single membrane-spanning sequence. This TNF pro-peptide, which itself displays biological activity, is usually proteolytically processed by a specific extracellular metallo-protease. Proteolytic cleavage occurs between residues 76 (Ala) and 77 (Val), yielding the mature (soluble) 157 amino acid TNF-a polypeptide. Mature human TNF-a appears to be devoid of a carbohydrate component, and contains a single disulfide bond. 

By means of gel electrophoresis on cross-linked, hydrolyzed starch,99 with simultaneous checking for proteins, lipids, and pectinesterase activity, it was found, however, that the product isolated after the separation on CM-Sephadex C-50 constitutes but one of five multiple forms of tomato pectinesterase, and is the one present in preponderant proportion98 (see Fig. 4). The accompanying lipid and sugar components were separated from this pectinesterase form in the course of the purification procedure. After analysis of the hydro-lyzate of the final product for fatty acids, as well as for carbohydrate components, it was possible to exclude the possibility of a lipoprotein,30 as well as glycoprotein,100 character of this form of tomato pectinesterase. 

A group of macromolecular polypeptides was also found in normal urine by Bode et al. (B5). These polypeptides, extracted from urine with a mixture of ethanol and ether followed by chloroform, contained also some lipid and carbohydrate components. 

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