title: Recombinant xylanase from Streptomyces coelicolor Ac-738: characterization and the effect on xylan-containing products.
abstract: A xylanase gene was isolated from the genomic DNA of Streptomyces coelicolor Ac-738. The 723-bp full-length gene encoded a 241-amino acid peptide consisting of a 49-residue putative TAT signal peptide and a glycoside hydrolase family-11 domain. The mature enzyme called XSC738 was expressed in Escherichia coli M15[pREP4]. The electrophoretically homogeneous protein with a specific activity of 167 U/mg for beechwood xylan was purified. The pH optimum of XSC738 was at pH 6; a high activity was retained within a pH range of 4.5-8.5. The enzyme was thermostable at 50-60 °C and retained an activity at pH 3.0-7.0. Xylanase XSC738 was activated by Mn²⁺, Co²⁺ and largely inhibited by Cd²⁺, SDS and EDTA. The products of xylan hydrolysis were mainly xylobiose, xylotriose, xylopentaose and xylohexose. Xylotetraose appeared as a minor product. Processing of such agricultural xylan-containing products as wheat, oats, soy flour and wheat bran by xylanase resulted in an increased content of sugars.
authors.affiliation: G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences (IBPM RAS), 5 Prospekt Nauki, 142290, Pushchino, Moscow Region, Russia, ssl204@rambler.ru.
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Lisov
authors.forename: Oksana V
authors.initials: OV
authors.lastname: Belova
authors.forename: Zhanna I
authors.initials: ZI
authors.lastname: Andreeva-Kovalevskaya
authors.forename: Zhanna I
authors.initials: ZI
authors.lastname: Budarina
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Solonin
authors.forename: Nataliya G
authors.initials: NG
authors.lastname: Vinokurova
authors.forename: Alexey A
authors.initials: AA
authors.lastname: Leontievsky
mesh_terms: D018554:Avena / Q000378:metabolism; D020536:Enzyme Activators / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000378:metabolism; D004795:Enzyme Stability; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D015870:Gene Expression; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000378:metabolism; D008970:Molecular Weight; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D048372:Streptomyces coelicolor / Q000201:enzymology* / Q000235:genetics; D013696:Temperature; D014908:Triticum / Q000378:metabolism; D014990:Xylans / Q000378:metabolism; D014995:Xylosidases / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D020536:Enzyme Activators; D004791:Enzyme Inhibitors; D008670:Metals; D011994:Recombinant Proteins; D014990:Xylans; D014995:Xylosidases