Endo-glycosidase

There is a clear distinction between exo- and endo-glycosidases the former act at the nonreducing end of a glycan chain, whereas the latter cleave at some point along an oligosaccharide chain, either at random or in a chemical environment -specific manner. 

Among the hydrolases are the widely distributed a-amylases, endo-glycosidases which hydrolyze... 

Exo-glycosidases Endo-glycosidases Glycos)mthases Transglycosylation Reverse hydrolysis Regio- and stereoselectivity... 

Targeted compounds include analogs of the H-type 2 [146,147] and Lewis [148,149] antigens as well as a wide range of potential endo-glycosidase inhibitors. 

Oligosaccharides containing 5-thiopyranosyl units are potentially resistant to hydrolysis by exo or endo glycosidases and constitute tools to investigate oligosaccharide-receptor interactions. 

All isoforms of N-CAM appear to be heavily glycosylated (Fig. 7a) as shown by significantly reduced sizes of the polypeptides obtained from tunicamycin-treated cells or after endo-glycosidase treatment. The presence of O-glycans has not been described so far but it is intriguing that the extra sequence of 37 amino-acid residues introduced by utilization of exons a-d contains eleven residues each of proline and serine/threonine [61] and hence is a good candidate for modification by D-glycosylation. 

Endo-glycosidases are also becoming important as agents for achieving partial degradation of saccharides, with the release of fragments that can then be separately sequenced. As more, pure glycosidases become commercially... 

Takahashi N (1992) Glycosamidases. In Takahashi N, Muramatsu T (eds) CRC Handbook of endo-glycosidases and glycoamidases. CRC Press Inc., Boca Raton, FL, pp 183-198 Tiwari S, Weissman AM (2001) Endoplasmic reticulum (ER)-associated degradation of T cell receptor subunits. Involvement of ER-associated ubiquitin-conjugating enzymes (E2s). J Biol Chem 276 16193-16200... 

M. Ito and T. Yamagata, Purification and characterization of glycosphingolipid-specific endo-glycosidases (endoglytxxeramidases) from a mutant strain of Rhodococcus sp. J. Biol Chem., 1989, 264, 9510 9519. 

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