Structure and Role of Carbohydrate in Freezing Point-depressing Glycoproteins from an Antarctic Fish

摘要: Abstract The linkage between the galactose and N-acetylgalactosamine of disaccharide attached to every threonine freezing point-depressing glycoproteins from antarctic fish, Trematomus borchgrevinki, has been previously suggested be β, 1–3 or 1–4, rather than 1–6. This paper reports some colorimetric chemical evidence favoring a linkage. Unsubstituted chromogen is formed breakdown upon β elimination with 0.05 m Na2CO3, indicating was proven type by release terminal when small glycopeptides, obtained hydrolysis elastate, were incubated β-galactosidase (Escherichia coli). Enzymatic oxidation C-6 hydroxyls aldehydes oxidase resulted in fully active glycoprotein. activity lost, however, conversion these newly negatively charged groups, either carboxyl groups halogen formation bisulfite addition products.