title: Fucosyltransferases produce N-glycans containing core l-galactose.
abstract: l-Galactose (l-Gal) containing N-glycans and cell wall polysaccharides have been detected in the l-Fuc deficient mur1 mutant of Arabidopsis thaliana. The l-Gal residue is thought to be transferred from GDP-l-Gal, which is a structurally related analog of GDP-l-Fuc, but in vitrol-galactosylation activity has never been detected. In this study, we carried out preparative scale GDP-l-Gal synthesis using recombinant A. thaliana GDP-mannose-3',5'-epimerase. We also demonstrated the l-galactosylation assay of mouse α1,6-fucosyltransferase (MmFUT8) and A. thaliana α1,3-fucosyltransferase (AtFucTA). Both fucosyltransferases showed l-galactosylation activity from GDP-l-Gal to asparagine-linked N-acetyl-β-d-glucosamine of asialo-agalacto-bi-antennary N-glycan instead of l-fucosylation. In addition, the apparent Kmvalues of MmFUT8 and AtFucTA suggest that l-Fuc was preferentially transferred to N-glycan compared with l-Gal by fucosyltransferases. Our results clearly demonstrate that MmFUT8 and AtFucTA transfer l-Gal residues from GDP-l-Gal and synthesize l-Gal containing N-glycan in vitro.
authors.affiliation: International Center for Biotechnology, Osaka University, Yamada-oka 2-1, Suita, Osaka 565-0871, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ohashi
authors.affiliation: International Center for Biotechnology, Osaka University, Yamada-oka 2-1, Suita, Osaka 565-0871, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Ohashi
authors.affiliation: International Center for Biotechnology, Osaka University, Yamada-oka 2-1, Suita, Osaka 565-0871, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kajiura
authors.affiliation: International Center for Biotechnology, Osaka University, Yamada-oka 2-1, Suita, Osaka 565-0871, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Misaki
authors.affiliation: Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Kitamura
authors.affiliation: International Center for Biotechnology, Osaka University, Yamada-oka 2-1, Suita, Osaka 565-0871, Japan. Electronic address: fujiyama@icb.osaka-u.ac.jp.
authors.forename: Kazuhito
authors.initials: K
authors.lastname: Fujiyama
mesh_terms: D000818:Animals; D017360:Arabidopsis / Q000201:enzymology; D029681:Arabidopsis Proteins / Q000235:genetics; D002238:Carbohydrate Epimerases / Q000378:metabolism; D005643:Fucose / Q000378:metabolism; D005647:Fucosyltransferases / Q000737:chemistry / Q000378:metabolism*; D005690:Galactose / Q000378:metabolism*; D006031:Glycosylation; D051379:Mice; D011134:Polysaccharides / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D011134:Polysaccharides; D011994:Recombinant Proteins; C476110:mur1 protein, Arabidopsis; D005643:Fucose; D005647:Fucosyltransferases; C031692:galactoside 3-fucosyltransferase; C020559:Glycoprotein 6-alpha-L-fucosyltransferase; D002238:Carbohydrate Epimerases; C019192:GDPmannose 3,5-epimerase; D005690:Galactose
keywords: Arabidopsis; Fucosyltransferase; GDP-d-mannose 3′,5′-epimerase; GDP-l-galactose; N-glycan