Release of oligosaccharides possessing reducing-end N-acetylgalactosamine from mucus glycoprotein in Streptomyces sp. OH-11242 culture medium through action of endo-type glycosidase.

A crude enzyme preparation from a culture medium of Streptomyces sp. OH-11242 contained endo-alpha-N-acetylgalactosaminidase activity. The activity could be induced by the addition of purified porcine gastric mucin to the culture medium. Oligosaccharides corresponding to approximately 2-14 glucose units were detected in the culture medium and also in an incubated reaction mixture of crude enzyme preparation and mucus glycoprotein. The resulting product with N-acetylgalactosamine at the reducing terminal implied the presence of a new type of endo-glycosidase liberating not only Gal beta 1-3GalNAc but also other larger oligosaccharides by hydrolysis of the O-glycosidic linkage between GalNAc and Ser (Thr).