Application of a novel endo-?-N-acetylglucosaminidase to isolate an entirely new class of bioactive compounds: N-glycans

Milk contains all essential nutrients such as proteins, lipids, carbohydrates, and minerals that help the development and growth of infants. In addition to these well-known compounds, milk also contains other structures that have not been fully characterized such as glycans. Glycans are important carbohydrate moieties attached to proteins and their synthesis takes place in the mammalian epithelial cells of animals. Although glycans are a small portion of the total dry mass of milk, there is a growing interest in these compounds because of their protective, stabilizing, and barrier functions. Further investigations of glycans are limited because of the lack of deglycosylation methods on a large scale and high-efficiency glycan release. Of the currently available methods, the enzymatic and chemical-based methods do not provide high-quality glycan release. They mostly cause the total destruction of released glycans and the remaining polypeptide structure. Recently, a novel N-glycosidase (EndoBI-1) that removes the N, N’-diacetyl chitobiose moiety from the N-glycan core of various glycoproteins has been isolated from the Bifidobacterium longum subsp. infantis ATCC 15697. © 2019 Elsevier Inc. All rights reserved.