title: Purification and characterization of D-xylose isomerase from Bifidobacterium adolescentis.
abstract: D-Xylose isomerase was purified to homogeneity from cell-free extracts of Bifidobacterium adolescentis by ammonium sulfate fractionation and chromatographies on DEAE-cellulose and Butyl-Toyopearl. The molecular weight of the purified enzyme was estimated to be 168,000 by gel filtration on TSKgel G-3000SW, and 53,000 on SDS-polyacrylamide gel electrophoresis. The optimum pH was around 7 and the enzyme was stable at pH 7-8. The enzyme required bivalent cations, Mg2+, Co2+, or Mn2+ for the activity, particularly Mn2+ to be best. The enzyme had a pI of 4.3, and the Km for D-xylose was 4 mM. The N-terminal amino acid sequence of the enzyme was not similar to those of D-xylose isomerases from other sources such as Clostridium thermosulfurogenes, Escherichia coli, or Bacillus subtilis.
authors.affiliation: Biochemical Research Institute, Nippon Menard Cosmetic Co., Ltd., Gifu, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kawai
authors.forename: H
authors.initials: H
authors.lastname: Konishi
authors.forename: H
authors.initials: H
authors.lastname: Horitsu
authors.forename: H
authors.initials: H
authors.lastname: Sakurai
authors.forename: K
authors.initials: K
authors.lastname: Takamizawa
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: K
authors.initials: K
authors.lastname: Kawai
mesh_terms: D019747:Aldose-Ketose Isomerases; D000595:Amino Acid Sequence; D000645:Ammonium Sulfate / Q000737:chemistry; D001644:Bifidobacterium / Q000201:enzymology*; D002238:Carbohydrate Epimerases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D002413:Cations, Divalent / Q000494:pharmacology; D002846:Chromatography, Affinity; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004789:Enzyme Activation / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D008970:Molecular Weight; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity
chemical_list: D002413:Cations, Divalent; D002238:Carbohydrate Epimerases; D019747:Aldose-Ketose Isomerases; C023298:xylose isomerase; D000645:Ammonium Sulfate