著者
Tadasu Urashima Jun Hirabayashi Sachiko Sato Akira Kobata
出版者
FCCA(Forum: Carbohydrates Coming of Age)
雑誌
Trends in Glycoscience and Glycotechnology (ISSN:09157352)
巻号頁・発行日
vol.30, no.172, pp.SE51-SE65, 2018-01-25 (Released:2018-01-25)
参考文献数
107
被引用文献数
108

It is now recognized that human milk oligosaccharides (HMOs) can function both as prebiotics and as decoy receptors that inhibit the attachment of pathogenic microorganisms to the colonic mucosa. They can also act as immune modulators and as colonic maturation stimulators in breast-fed infants. These functions could be mediated by biological interaction between a variety of HMOs and lectins including galectins, selectins and siglecs. There are more than 100 HMOs; they have structural units such as H type 1: Fucα1-2Galβ1-3GlcNAc, Lewis a: Galβ1-3(Fucα1-4)GlcNAc, Lewis b: Fucα1-2Galβ1-3(Fucα1-4)GlcNAc, Lewis x: Galβ1-4(Fucα1-3)GlcNAc, sialyl Lewis a: Neu5Acα2-3Galβ1-3(Fucα1-4)GlcNAc, and sialyl Lewis x: Neu5Acα2-3Galβ1-4(Fucα1-3)GlcNAc. It can be expected that these units may be utilized as tools for studies on the sugar-binding specificities of lectins including galectins, monoclonal antibodies, virus capsid proteins and bacterial toxins. This mini-review presents the dataset of comprehensive HMO structures, including recently clarified ones, in tabular form, for its utilization in such studies, including those of carbohydrate-binding specificity of galectins. In addition, this review introduces recent in vivo and clinical studies, which may be relevant to the biological functions and future utilization of HMOs.
著者
Akira KOBATA
出版者
日本学士院
雑誌
Proceedings of the Japan Academy, Series B (ISSN:03862208)
巻号頁・発行日
vol.89, no.3, pp.97-117, 2013-03-11 (Released:2013-03-11)
参考文献数
110
被引用文献数
4 34

Many glycosidases, which work as useful reagents for the studies of structures and functions of free and conjugated oligosaccharides, have been found and thoroughly purified. These enzymes are classified into exo- and endoglycosidases by their glycon specificities. Their usefulness and limits as reagents are explained in detail in this review.Endoglycosidases, which were originally found in the culture fluid of bacteria and in the extracts of plants, are now widely found in the mammals including humans. The physiological roles of these enzymes are discussed in relation to the oligosaccharides accumulated in the urine of patients with exoglycosidase deficiencies. Furthermore, PNGase is found to play important roles in the ER-associated degradation pathway of glycoproteins.Recent studies of the glycosidases in Bifidobacteria have revealed that GNB/LNB pathway, which uniquely exist in this bacteria, works for the expression of Bifidus factor activity of human milk oligosaccharides, an important topic in the baby nutrition. This interesting field will be introduced in detail in one section of this article.(Communicated by Kunihiko SUZUKI, M.J.A.)