Fialho, M. B. [UNESP]Carmona, E. C. [UNESP]2014-05-272014-05-272004-04-20Folia Microbiologica, v. 49, n. 1, p. 13-18, 2004.0015-5632http://hdl.handle.net/11449/67708A strain of Aspergillus giganteus cultivated in a medium with xylan produced two xylanases (xylanase I and II) which were purified to homogeneity. Their molar mass, estimated by SDS-PAGE, were 21 and 24 kDa, respectively. Both enzymes are glycoproteins with 50°C temperature optimum; optimum pH was 6.0-6.5 for xylanase I and 6.0 for xylanase II. At 50°C xylanase I exhibited higher thermostability than xylanase II. Hg2+, Cu 2+ and SDS were strong inhibitors, 1,4-dithiothreitol stimulated the reaction of both enzymes. Both xylanases are xylan-specific; kinetic parameters indicated higher efficiency in the hydrolysis of oat spelts xylan. In hydrolysis of this substrate, xylotriose, xylotetraose and larger xylooligosaccharides were released and hence the enzymes were classified as endoxylanases.13-18engammonium sulfatecopperdextrandithiothreitoldodecyl sulfate sodiumendo 1,4 beta xylanaseenzyme activatorenzyme inhibitorfungal proteinglycoproteinmercury derivativesephadexxylanAspergilluschemistryculture mediumenzyme specificityenzyme stabilityenzymologygel chromatographygrowth, development and agingisolation and purificationkineticsmetabolismmolecular weightpHpolyacrylamide gel electrophoresisprecipitationtemperatureAmmonium SulfateChromatography, GelCopperCulture MediaDextransDithiothreitolElectrophoresis, Polyacrylamide GelEndo-1,4-beta XylanasesEnzyme ActivatorsEnzyme InhibitorsEnzyme StabilityFractional PrecipitationFungal ProteinsGlycoproteinsHydrogen-Ion ConcentrationKineticsMercury CompoundsMolecular WeightSodium Dodecyl SulfateSubstrate SpecificityTemperatureXylansAspergillus giganteusArtigo10.1007/BF02931639WOS:000220630700003Acesso restrito2-s2.0-18424187654110421764783871