title: Purification and Characterization of a [beta]-D-Xylosidase and an Endo-Xylanase from Wheat Flour.
abstract: A [beta]-D-xylosidase and an endo-xylanase were purified from European wheat (Triticum aestivum) flour. The [beta]-D-xylosidase had a molecular weight of approximately 64,000 and an isoelectric point of 5.5. It hydrolyzed p-nitrophenyl-[beta]-D-xylopyranoside and xylo-oligosaccharides and released D-xylose units from wheat arabinoxylan and oat spelts xylan. An endo-xylanase with a molecular weight of approximately 55,000 was also obtained and it consisted of a number of isoforms with isoelectric points between 4.0 and 5.0. The action of the isolated endo-xylanase depended on the degree of substitution of the polysaccharide. Unbranched polymers were preferentially hydrolyzed. Since xylo-oligosaccharides were not hydrolyzed, the enzyme appeared to need at least five or more consecutive unsubstituted xylose units. Finally, an [alpha]-L-arabinofuranosidase that hydrolyzed p-nitrophenyl-[alpha]-L-arabinofuranoside was partially purified.
authors.affiliation: Nederlandse Organisatie voor Toegepast-Natuurwetenschappelyk Onderzoek, Nutrition and Food Research Institute, P.O. Box 360, NL-3700 AJ Zeist, The Netherlands (G.C., M.H.).
authors.forename: G.
authors.initials: G
authors.lastname: Cleemput
authors.forename: M.
authors.initials: M
authors.lastname: Hessing
authors.forename: M.
authors.initials: M
authors.lastname: Van Oort
authors.forename: M.
authors.initials: M
authors.lastname: Deconynck
authors.forename: J. A.
authors.initials: JA
authors.lastname: Delcour