title: Novel substrate specificities of two lacto-N-biosidases towards β-linked galacto-N-biose-containing oligosaccharides of globo H, Gb5, and GA1.
abstract: We describe the novel substrate specificities of two independently evolved lacto-N-biosidases (LnbX and LnbB) towards the sugar chains of globo- and ganglio-series glycosphingolipids. LnbX, a non-classified member of the glycoside hydrolase family, isolated from Bifidobacterium longum subsp. longum, was shown to liberate galacto-N-biose (GNB: Galβ1-3GalNAc) and 2'-fucosyl GNB (a type-4 trisaccharide) from Gb5 pentasaccharide and globo H hexasaccharide, respectively. LnbB, a member of the glycoside hydrolase family 20 isolated from Bifidobacterium bifidum, was shown to release GNB from Gb5 and GA1 oligosaccharides. This is the first report describing enzymatic release of β-linked GNB from natural substrates. These unique activities may play a role in modulating the microbial composition in the gut ecosystem, and may serve as new tools for elucidating the functions of sugar chains of glycosphingolipids.
authors.affiliation: Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, Japan.
authors.forename: Aina
authors.initials: A
authors.lastname: Gotoh
authors.affiliation: Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Katoh
authors.affiliation: Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Sugiyama
authors.affiliation: Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, Japan.
authors.forename: Shin
authors.initials: S
authors.lastname: Kurihara
authors.affiliation: Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Honda
authors.affiliation: Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, Japan.
authors.forename: Haruko
authors.initials: H
authors.lastname: Sakurama
authors.affiliation: Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
authors.forename: Taiho
authors.initials: T
authors.lastname: Kambe
authors.affiliation: Faculty of Biology-Oriented Science and Technology, Kinki University, Wakayama 649-6493, Japan.
authors.forename: Hisashi
authors.initials: H
authors.lastname: Ashida
authors.affiliation: National Food Research Institute, National Agriculture and Food Research Organization, Tsukuba, Ibaraki 305-8642, Japan.
authors.forename: Motomitsu
authors.initials: M
authors.lastname: Kitaoka
authors.affiliation: Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Ishikawa Prefectural University, Nonoichi, Ishikawa 921-8836, Japan; Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan. Electronic address: takane@ishikawa-pu.ac.jp.
authors.forename: Takane
authors.initials: T
authors.lastname: Katayama
mesh_terms: D015295:Antigens, Tumor-Associated, Carbohydrate / Q000737:chemistry; D001426:Bacterial Proteins / Q000302:isolation & purification / Q000378:metabolism; D001644:Bifidobacterium / Q000201:enzymology*; D006026:Glycoside Hydrolases / Q000302:isolation & purification / Q000378:metabolism*; D009844:Oligosaccharides / Q000737:chemistry*; D013379:Substrate Specificity
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate; D001426:Bacterial Proteins; C472765:Globo-H; D009844:Oligosaccharides; C016467:Thomsen-Friedenreich antigen; D006026:Glycoside Hydrolases; C076748:lacto-N-biosidase
keywords: GA1; Gb5; Globo H; Lacto-N-biosidase; β-Linked galacto-N-biose