Endoglycosidase H (Endo H) is a recombinant glycosidase cloned from Streptomyces plicatus and overexpressed in E. coli. Endo H cleaves the chitobiose core of high mannose and a limited number of hybrid oligosaccharides from N-linked glycoproteins. It does not cleave complex glycans. Enzymatic cleavage is between the two N-acetylglucosamine residues in the diacetylchitobiose core of the oligosaccharide, leaving one N-acetylglucosamine residue on the asparagine. This is in contrast to PNGase F, which cleaves all asparagine-linked oligosaccharides.
Unit Definition: One unit is defined as the amount of enzyme required to remove >95% of the carbohydrate from 10μg of denatured RNase B in 1 hour at 37°C in a total reaction volume of 10μl.