Glycan chains

Secretory proteins and proteins destined for membranes distal to the ER completely traverse the membrane bilayer and are discharged into the lumen of the ER. 7V-Glycan chains, if present, are added (Chapter 47) as these proteins traverse the irmer part of the ER membrane—a process called cotranslational glycosyla-tion. Subsequently, the proteins are found in the... 

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

Hereditary erythroblastic multinuclearity witha positive acidified serum lysis test (congenital dyserythropoietic anemia type II). This is a relatively mild form of anemia. It reflects at least in part the presence in the red cell membranes of various glycoproteins with abnormal N-glycan chains, which contribute to the susceptibility to lysis. 

Type II disorders are due to mutations in genes encoding enzymes (eg, GIcNAc transferase-2, causing CDG lla) involved in the processing of N-glycan chains... 

With this solid-phase methodology in hand, the synthesis of branched oligosaccharides could be investigated. This led to the preparation of pentasaccharide 15 related to /V-glycan chains (Scheme 4.5).3... 

Dan, A. Lergenmuller, M. Amano, M. Nakahara, Y. Ogawa, T. Ito, Y., p-Methoxybenzylidene-tethered beta-mannosylation for stereoselective synthesis of asparagine-linked glycan chains. Chem. Eur. J. 1998,4, 2182-2190. 

One of the most difficult aspects of the study of glycoprotein structure is the remarkable heterogeneity displayed in their glycan chains. The l.c. 

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