Glycosylated substance

The biological activity of the synthetic glycosylated substance P derivatives was studied by measuring their effects on muscle contraction of longitudinal... 

Albumins are a family of globular proteins, the most common of which is serum albumin. The albumin family consists of aU proteins that are water-soluble, are moderately soluble in concentrated salt solutions, and experience heat denatura-tion. Albumins are commonly found in blood plasma they are unique from other blood proteins in that they are not glycosylated. Substances containing albumins, such as egg white, are called albuminoids. Commercially, albumins are obtained insignificant quantities from egg white (ovalbumin), bovine serum (bovine serum albumin, BSA), and human serum (human serum albumin, HSA). They are also available from soybeans, milk, and grains [101-103]. 

The most frequent protein in the plasma, at around 45 g is albumin. Due to its high concentration, it plays a crucial role in maintaining the blood s colloid osmotic pressure and represents an important amino acid reserve for the body. Albumin has binding sites for apolar substances and therefore functions as a transport protein for long-chain fatty acids, bilirubin, drugs, and some steroid hormones and vitamins. In addition, serum albumin binds Ca "" and Mg "" ions. It is the only important plasma protein that is not glycosylated. 

The best known inhibitors of glycosylation of proteins interfere with the lipid-dependent steps.35,228 Substances that specifically block reactions taking place after the transfer of the oligosaccharide to the protein are little known. As several, incompletely (or differently) glycosylated, viral glycoproteins arc still biologically active (see Section IV), these substances would escape the screening procedure based on... 

Flavones contribute to plant tissue color provided that they occur in high concentrations or are complexed with metal ions. Some flavones participate in taste for example, the highly methoxylated aglycones nobiletin, sinensetin and tangeretin are responsible for the bitter taste of citrus peel. On the other hand, some glycosylated flavones (for instance neodiosmin and rhoifolin) reduce the bitterness of some substances (limonin, naringin, caffeine, quinine) [2]. 

P. Gamer and J. M. Park, Glycosyl a-amino acids via stereocontrolled buildup of a penaldic acid equivalent. A novel synthetic approach to the nucleosidic component of the polyoxins and related substances, J. Org. Chem. 55 3772 (1990). 

Vercellotti et al. (65) studied the rates of / -elimination for O-benzyl ethers of O-glycosyl-N-(2,4-dinitrophenyl)-L-serine and L-threonine methyl esters in non-aqueous solvents using various bases. The corresponding acetyl derivatives of 2-acetamido-2-deoxy-D-galactose were also included. Generally, these substances were highly reactive, but the nature of the solvent and the base type were influencing factors. Thus, no elimination occurred in benzene when trimethylamine was used as base. 

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