Tetraantennary glycans

EPO Tetraantennary complex type at three Asn sites and one O-linked glycans. More O-linked glycans and less sialic acid than native form manifest conformational differences and hence in the potency One O-linked and three N-linked glycans. N-linked glycans are extensively branched and complex type structure having tetraantennary glycans [212,215]... 

Fig. 2. Highly fucosylated tetraantennary glycans from al-acid glycoprotein from a cirrhotic patient.

The structure of some of these oligosaccharides has been determined. A major N-glycan representing about 45% of the carbohydrate chains is a monosialylated monofucosylated diantennary glycan of the V-acetyllactosaminic type (Fig. 12A)[81]. A tetraantennary glycan of the V-acetyllactosaminic type has also been isolated and its structure determined by methylation analysis and 500MHz H-NMR (Fig. 12B)[82]. The major O-glycan of human vWf was shown to be a diantennary tetrasaccharide (Fig. 12C)[83]. 

Fig. 12. (A,B) Di- and tetraantennary glycans and (C) 0-linked branched tetrasaccharide from von Willebrand factor.

Fig. 13. (A) Diantennary, (B) triantennary and (C) tetraantennary glycans and 0-linked (D) hexa-, (E) tri-, (F) tetra-, and (G) pentasaccharides from glycoprotein Iba.

M, oligomannosidic type L, A -acetyllactosaminic type bi, tri, tetra bi, tri and tetraantennary glycans, respectively. 

B54. Bories, P. N., Feger, L, Benbernou, N., Rouzeau, J. D., Agneray, J., and Durand, G. Prevalence of tri- and tetraantennary glycans of human alpha 1- acid glycoprotein in release of macrophage inhibitor of interleukin-1 activity. Inflammation 14, 315-323 (1990). 

Fig. 6. (A-C,E) Di-, (F,H,1) tri- and (G) tetraantennary complex type and (D) high mannose type triantennary glycans from factor Vlll.

Fig. 7. Conformations of (a) tetraantennary and (b) biantennary glycans. The amino acid residue asparagine (ASN) is at the bottom in both cases.

Scheme 16.28. MPEG-supported synthesis of tetraantennary complex-type A/-glycans.

M. Sequencing of tri- and tetraantennary A -glycans containing siaUc acid by negative mode ESI QTOF tandem MS. J. Am. Soc. Mass Spectrom. 2002, 13, 1138-1148. 

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