title: Characterization of a novel β-L-arabinofuranosidase in Bifidobacterium longum: functional elucidation of a DUF1680 protein family member.
abstract: Pfam DUF1680 (PF07944) is an uncharacterized protein family conserved in many species of bacteria, actinomycetes, fungi, and plants. Previously, we cloned and characterized the hypBA2 gene as a β-L-arabinobiosidase in Bifidobacterium longum JCM 1217. In this study, we cloned a DUF1680 family member, the hypBA1 gene, which constitutes a gene cluster with hypBA2. HypBA1 is a novel β-L-arabinofuranosidase that liberates L-arabinose from the L-arabinofuranose (Araf)-β1,2-Araf disaccharide. HypBA1 also transglycosylates 1-alkanols with retention of the anomeric configuration. Mutagenesis and azide rescue experiments indicated that Glu-338 is a critical residue for catalytic activity. This study provides the first characterization of a DUF1680 family member, which defines a new family of glycoside hydrolases, the glycoside hydrolase family 127.
authors.affiliation: From the Faculty of Agriculture, Kagoshima University, Korimoto, Kagoshima 890-0065, Japan.
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Fujita
authors.forename: Yukari
authors.initials: Y
authors.lastname: Takashi
authors.forename: Eriko
authors.initials: E
authors.lastname: Obuchi
authors.forename: Kanefumi
authors.initials: K
authors.lastname: Kitahara
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Suganuma
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D001089:Arabinose / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D001644:Bifidobacterium / Q000201:enzymology* / Q000254:growth & development; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D002855:Chromatography, Thin Layer; D004591:Electrophoresis, Polyacrylamide Gel; D005285:Fermentation; D006023:Glycoproteins / Q000378:metabolism; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000378:metabolism*; D006031:Glycosylation; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D008954:Models, Biological; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D050505:Mutant Proteins / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D020539:Sequence Analysis, Protein; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D000596:Amino Acids; D001426:Bacterial Proteins; D006023:Glycoproteins; D050505:Mutant Proteins; D011994:Recombinant Proteins; C431714:arabinofuranose; D001089:Arabinose; D006026:Glycoside Hydrolases
keywords: Bacteria; Cloning; Enzyme Catalysis; Enzyme Kinetics; Glycosidases; Hydrolases; Hydroxyproline; Mutagenesis; Protein Expression