Sialic acids chains

Endo-a-N- acetylgalactosamidase D Diplococcus pneumoniae 160 7.6 Removes the unsubstituted disaccharide Gaipi-3GalNAc from o-glycosylated proteins removes sialic acid chains with at least 5 sections. ... 

L-asparagine N-linked oligosaccharide of neural cell adhesion molecule terminated with poly sialic acid chains, where n = 20-100. 

Tome, Y., Hirohashi, S., Noguchi, M., Matsuno, Y., and Shimosato, Y., 1993, Comparison of immunoreactivity between two different monoclonal antibodies recognizing peptide and poly-sialic acid chain epitopes on the neural cell adhesion molecule in normal tissues and lung tumors, Acta Pathol. Jpn. 43 168-175. 

Troy, F. A., Janas, T, Janas, T, and Merker, R. I., 1990a, Transmembrane translocation of poly-sialic acid chains across the inner membrane of neuroinvasive E. coli Kl, Glycoconj. J. 8 152. 

Factor V. High in sialic acid content. Factor V is a large asymmetric single-chain glycoprotein that becomes an active participant in the coagulation cascade when it is converted to its active form by a-thrombin. Approximately 25% of human Factor V is found in the whole blood associated with platelets. Factor V is an essential cofactor along with Factor Xa plus phosphohpid plus Ca " in the conversion of prothrombin to thrombin. 

In addition to binding to sialic acid residues of the carbohydrate side chains of cellular proteins that the virus exploits as receptors, hemagglutinin has a second function in the infection of host cells. Viruses, bound to the plasma membrane via their membrane receptors, are taken into the cells by endocytosis. Proton pumps in the membrane of endocytic vesicles that now contain the bound viruses cause an accumulation of protons and a consequent lowering of the pH inside the vesicles. The acidic pH (below pH 6) allows hemagglutinin to fulfill its second role, namely, to act as a membrane fusogen by inducing the fusion of the viral envelope membrane with the membrane of the endosome. This expels the viral RNA into the cytoplasm, where it can begin to replicate. 

Sesquiterpenoid. 203, 1071 Sex hormone, 1082-1083 Sharpless, K. Barry. 734 Sharpless epoxidation, 735 Shell (electron), 5 capacity of, 5 Shielding (NMR). 442 Si prochirality, 315-316 Sialic acid. 997 Side chain (amino acid), 1020 Sigma (cr) bond, 11 symmetry of, 11 Sigmatropic rearrangement, 1191-1195... 

Accordingly, they generally contain either N- or O-hnked oligosaccharide chains, or both (Chapter 47). Albumin is the major exception it does not contain sugar residues. The ohgosaccharide chains have various functions (Table 47-2). Removal of terminal sialic acid... 

Figure 1.35 The complex structure of an asparagine-linked polysaccharide. Note the branched nature of polymer with terminal sialic acid residues on each chain. 

D-Galactose Residue within Polysaccharide Chain with Terminal Sialic Acid Groups... 

C5-derived peptide in serum. This molecule lacks anaphylatoxin activity (i.e. it cannot cause smooth muscle contraction), and its ability to cause che-motaxis in neutrophils is about 10-20 times lower than that of C5a. However, human serum also contains a heat-stable, anionic protein termed co-chemotaxin (relative molecular mass = 60 kDa), which acts in a concentration-dependent manner to permit C5a des Arg to act as a chemoattractant for neutrophils. Thus, C5a des Arg plus cochemotaxin working together probably account for most of the neutrophil chemoattractant activity in vivo following complement activation. The mechanism of action of cochemotaxin is unknown, but it may form a physical complex by attaching to a sialic acid residue on the oligosaccharide chain of C5a des Arg. Deglycosylation of C5a des Arg increases its chemoattractant activity more than 10-fold, and its dependency upon cochemotaxin is decreased. 

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