title: Unique sugar metabolic pathways of bifidobacteria.
abstract: Bifidobacteria have many beneficial effects for human health. The gastrointestinal tract, where natural colonization of bifidobacteria occurs, is an environment poor in nutrition and oxygen. Therefore, bifidobacteria have many unique glycosidases, transporters, and metabolic enzymes for sugar fermentation to utilize diverse carbohydrates that are not absorbed by host humans and animals. They have a unique, effective central fermentative pathway called bifid shunt. Recently, a novel metabolic pathway that utilizes both human milk oligosaccharides and host glycoconjugates was found. The galacto-N-biose/lacto-N-biose I metabolic pathway plays a key role in colonization in the infant gastrointestinal tract. These pathways involve many unique enzymes and proteins. This review focuses on their molecular mechanisms, as revealed by biochemical and crystallographic studies.
authors.affiliation: Department of Biotechnology, The University of Tokyo, Tokyo, Japan. asfushi@mail.ecc.u-tokyo.ac.jp
authors.forename: Shinya
authors.initials: S
authors.lastname: Fushinobu
mesh_terms: D000818:Animals; D001644:Bifidobacterium / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D050260:Carbohydrate Metabolism; D002240:Carbohydrate Sequence; D002241:Carbohydrates; D005110:Extracellular Space / Q000201:enzymology; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D053858:Metabolic Networks and Pathways; D008895:Milk, Human / Q000737:chemistry / Q000378:metabolism; D008969:Molecular Sequence Data
chemical_list: D002241:Carbohydrates; D006026:Glycoside Hydrolases