O-glycans

Exhibit high content of O-glycan chains, usually containing NeuAc. 

Glycophorins A, B, and C are also transmembrane glycoproteins but of the single-pass type, extending across the membrane only once. A is the major gly-cophorin, is made up of 131 amino acids, and is heavily glycosylated (about 60% of its mass). Its amino terminal end, which contains 16 oligosaccharide chains (15 of which are O-glycans), extrudes out from the surface of... 

Bannert N, Craig S, Farzan M, et al. Sialylated O-glycans and sulfated tyrosines in the NH2-terminal domain of CC chemokine receptor 5 contribute to high affinity binding of chemokines. J Exp Med 2001 194(11) 1661-1673. 

Fig. 15.3. Structures of the four most commonly observed O-glycan cores.

M. Fukuda, Role of mucin-type O-glycans in cell adhesion, Biochim. Biophys. Acta, 1573 (2002) 394-A05. 

T. A. Gerken, Kinetic modeling confirms the biosynthesis of mucin core 1 (/i-Gal (1 -3)x-Gal YAc-O-Ser/Thr) O-glycan structures are modulated by neighboring glycosylation effects, Biochemistry, 43 (2004) 4137—4142. 

For instance, in a tour de force analysis, Florea et al45 were able to determine the complete structure of 59 O-glycans (ranging in size from... 

O-glycans. Recently, evidence for the existence of inborn errors in the biosynthesis of core 1 mucin type O-glycans have been described [30]. 

Fig. 21.3. Protein glycosylation of S. mansoni cercariae. Cercarial /V-glycan structures were reported by Khoo et ai. (2001) [1], O-glycan structures were elucidated by Fluang et ai. (2001) [2] and Khoo et ai. (1995) [3],...

Fig. 21.7. Glycosphingolipids and protein glycosylation of Cyclophyllida. Glycolipids of E. multilocularis were analysed by Persat et al. (1990) [1] and (1992) [2]. Glycolipids of T. crassiceps and M. coturnix were characterized by Dennis et al. (1992) [3] and Nishimura etal. (1991) [4], respectively. The major glycolipid of T. solium was analysed by Lopez-Marin etal. (2002) [5], Cer, ceramide. A/-glycans of E. granulosus and O-glycans of . multilocularis were described by Khoo etal. (1997c) [6] and Hulsmeier et al. (2002) [7], respectively. Possible Gala1-4)Gal1- structural elements are boxed.

Huang, H.H., Tsai, P.L. and Khoo, K.H. (2001) Selective expression of different fucosylated epitopes on two distinct sets of Schistosoma mansoni cercarial O-glycans identification of a novel core type and Fewis X structure. Glycobiology 11, 395 106. 

Khoo, K.H., Sarda, S., Xu, X., Caulfield, J.P., McNeil, M.R., Homans, S.W., Morris, H.R. and Dell, A. (1995) A unique multifucosylated -3GalNAc(i1 -4GlcNAc(i1 -3Gala1 - motif constitutes the repeating unit of the complex O-glycans derived from the cercarial glycocalyx of Schistosoma mansoni. journal of Biological Chemistry 270, 1 71 14-17123. 

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