Glycans types

Total complement of glycans (type of carbohydrate molecule) in an organism (glycome). 

Year Array Type of Glycans Glycan Type Glycan Source Immobilization Method Application References... 

Plasma protein glycoforms rich in diantennary complex type N-glycans (type 1) increase in acute infections, while in some diseases with chronic inflammatory changes, more branched N-glycans (type II) increase. In sera from 109 human immunodeficiency... 

Figure 1 Characteristic carbohydrate moieties serve as markers for biological recognition. Af-Glycan type II chains (Gaipi 4GlcNAc) in the tri-antennary cluster configurations with (Tri-II) and without sialic acid terminal residues (asialo-Tri-II). The asialo-Tri-II sugar moieties but not the Tri-II structures are specifically targeted by a horse-neutralization antibody of SARS-CoV (68).

A peptidoglycan, of different type from that of other species of Cellulo-monas, has been isolated from C. cartalyticum L-Lysine replaces ornithine and the interpeptide bridge consists of d-aspartyl-D-serine. The same peptido-glycan type has been identified in Arthrobacter luteus, Brevibacterium liticum, and Corynebacterium manihot. 

The great flexibility of this glycan-type conformation is based on the nature of the connecting bridge between the monomers. The bridge has three free rotational bonds and, furthermore, the sugar residues are further apart ... 

Natural monosaccharide target Unnaiial monosaccharide Glycan types labeled HO OH AcO OAc... 

L-Fucosamine was found as a constituent of Pneumococcus Type V capsular polysaccharide and as a constituent of the mucopolysaccharides (glycosamino-glycans) of certain enteric bacteria A new synthesis was devised to make the amino sugar more available. 

A general term for a polysaccharide (glycan) composed of a single type of monosaccharide residue is obtained by replacing the ending -ose of the sugar name by -an . 

When substitution occurs in a polysaccharide (glycan), each type of sub cited in the name at an appropriate position (in alphabetical order). 

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... 

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... 

Maras, M., Saelens, X., Laroy, W. et al. (1997) In vitro conversion of the carbohydrate moiety of fungal glycoproteins to mammalian-type oligosaccharides - evidence for JV-acetylglucosaminyltransferase-I-accepting glycans from Trichoderma reesei. European Journal of Biochemistry, 249 (3), 701-707. 

Parasitism by T. spiralis has been a subject of scientific interest for over 150 years. Recently, considerable attention has been paid to the parasite by immunologists interested in immunity to nematodes in general, and mucosal immunity in particular. It has been shown that glycan-specific antibodies are highly effective mediators of host defence against intestinal 7. spiralis infection. Protective monoclonal antibodies have been used to elucidate mechanisms of worm expulsion, as well as to identify molecules that the parasite uses to create its niche. In the future, detailed characterization of these molecules and their functions should afford additional insights into parasitism by Trichinella spiralis, and possibly also by other types of pathogen. 

A fourth family of A-glycans are referred to as hybrid glycans. These glycans share structural features of the high mannose and complex-type families. They usually retain two mannoses on the 6-arm of the trimannosyl core whilst complex-type antennae are elaborated on the 3-arm. Hybrid structures are frequentiy bisected and may also be core fucosylated (Fig. 15.1). It should be noted that whilst core fucosylation is common in complex-type, hybrid and truncated glycans, it is rarely found in high mannose glycans. 

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