HighpurityArABInoxylan(WheatFlour;Insoluble)foruseinresearch,biochemicalenzymeassaysandinvitrodiagnosticanalysis.Purity~80%.Carefullyextractedandpurifiedtomaintaintheferulicacidcrosslinksinthenativearabinoxylan.Treatedtoremovestarch,β-glucanandprotein.Ara:Xyl=36:51.Glucose6.5%,mannose4.4%andgalactose1.6%Novelsubstratesfortheautomatedandmanualassayofendo-1,4-β-xylanase.Mangan,D.,Cornaggia,C.,Liadova,A.,McCormack,N.,Ivory,R.,McKie,V.A.,Ormerod,A.&McCleary,D.V.(2017).CarbohydrateResearch,445,14-22.LinktoArticleReadAbstractendo-1,4-β-Xylanase(EC3.2.1.8)isemployedacrossabroadrangeofindustriesincludinganimalfeed,brewing,baking,biofuels,detergentsandpulp(paper).Despiteitsimportance,arapid,reliable,reproducIBLe,automatableassayforthisenzymethatisbasedontheuseofachemicallydefinedsubstratehasnotbeendescribedtodate.Reportedhereinisanewenzymecoupledassayprocedure,termedtheXylX6assay,thatemploysanovelsubstrate,namely4,6-O-(3-ketobutylidene)-4-nitrophenyl-β-45-O-glucosyl-xylopentaoside.ThedevelopmentofthesubstrateandassociatedassayisdiscussedhereandtherelationshipbetweentheactivityvaluesobtainedwiththeXylX6assayversustrADItionalreducingsugarassaysanditsspecificityandreproducibilitywerethoroughlyinvestigated.Hydrolysisofwheatflourarabinoxylan,acid-debranchedwheatflourarabinoxylanandarabino-xylo-oligosaccharidesbyβ-xylanase,α-L-arabinofuranosidaseandβ-xylosidase.McCleary,B.V.,McKie,V.A.,Draga,A.,Rooney,E.,Mangan,D.&Larkin,J.(2015).CarbohydrateResearch,407,79-96.LinktoArticleReadAbstractArangeofα-L-arabinofuranosyl-(1-4)-β-D-xylo-oligosaccharides(AXOS)wereproducedbyhydrolysisofwheatflourarabinoxylan(WAX)andaciddebranchedarabinoxylan(ADWAX),inthepresenceandabsenceofanAXH-d3α-L-arabinofuranosidase,byseveralGH10andGH11β-xylanases.ThestructuresoftheoligosaccharideswerecharacterisedbyGC-MSandNMRandbyhydrolysisbyarangeofα-L-arabinofuranosidasesandβ-xylosidase.TheAXOSwerepurifiedandusedtocharacterisetheactionpatternsofthespecificα-L-arabinofuranosidases.Theseenzymes,incombinationwitheitherCellvibriomixtusorNeocallimastixpatriciarumβ-xylanase,wereusedtoproduceelevatedlevelsofspecificAXOSonhydrolysisofWAX,suchas32-α-L-Araf-(1-4)-β-D-xylobiose(A3X),23-α-L-Araf-(1-4)-β-D-xylotriose(A2XX),33-α-L-Araf-(1-4)-β-D-xylotriose(A3XX),22-α-L-Araf-(1-4)-β-D-xylotriose(XA2X),32-α-L-Araf(1-4)-β-D-xylotriose(XA3X),23-α-L-Araf-(1-4)-β-D-xylotetraose(XA2XX),33-α-L-Araf-(1-4)-β-D-xylotetraose(XA3XX),23,33-di-α-L-Araf-(1-4)-β-D-xylotriose(A2+3XX),23,33-di-α-L-Araf-(1-4)-β-D-xylotetraose(XA2+3XX),24,34-di-α-L-Araf-(1-4)-β-D-xylopentaose(XA2+3XXX)and33,34-di-α-L-Araf-(1-4)-β-D-xylopentaose(XA3A3XX),manyofwhichhavenotpreviouslybeenproducedinsufficientquantitiestoallowtheiruseassubstratesinfurtherenzymicstudies.ForA2,3XX,yieldsofapproximately16%ofthestartingmaterial(wheatarabinoxylan)havebeenachieved.Mixturesoftheα-L-arabinofuranosidases,withspecificactiononAXOS,havebeencombinedwithβ-xylosidaseandβ-xylanasetoobtainanoptimalmixtureforhydrolysisofarabinoxylantoL-arabinoseandD-xylose.Generationoftransgenicwheat(TriticumaestivumL.)accumulatingheterologousendo‐xylanaseorferulicacidesteraseintheendosperm.Harholt,J.,Bach,I.C.,Lind‐Bouquin,S.,Nunan,K.J.,Madrid,S.M.,Brinch‐Pedersen,H.,Holm,P.B.&Scheller,H.V.(2010).PlantBiotechnologyJournal,8(3),351-362.LinktoArticleReadAbstractEndo-xylanase(fromBacillussubtilis)orferulicacidesterase(fromAspergillusniger)wereexpressedinwheatunderthecontroloftheendosperm-specific1DX5gluteninpromoter.Constructsbothwithandwithouttheendoplasmicreticulumretentionsignal(Lys-Asp-Glu-Leu)KDELwereused.TransgenicplantswererecoveredinallfourcasesbutnoqualitativedifferencescouldbeobservedwhetherKDELwasaddedornot.Endo-xylanaseactivityintransgenicgrainswasincreasedbetweentwoandthreefoldrelativetowildtype.Thegrainswereshrivelledandhada25%–33%decreaseinmass.Extensiveanalysisofthecellwallsshoweda10%–15%increaseinarabinosetoxyloseratio,a50%increaseintheproportionofwater-extractablearabinoxylan,andashiftintheMWofthewater-extractablearabinoxylanfrombeingmainlylargerthan85kDtobeingbetween2and85kD.Ferulicacidesterase-expressinggrainswerealsoshrivelled,andtheseedweightwasdecreasedby20%–50%.Noferulicacidesteraseactivitycouldbedetectedinwild-typegrainswhereasferulicacidesteraseactivitywasdetectedintransgeniclines.Thegraincellwallshad15%–40%increaseinwater-unextractablearabinoxylanandadecreaseinmonomericferulicacidbetween13%and34%.Inalltheplants,theobservedchangesareconsistentwithaplantresponsethatservestominimizetheeffectoftheheterologouslyexpressedenzymesbyincreasingarabinoxylanbiosynthesisandcross-linking.Arsenalofplantcellwalldegradingenzymesreflectshostpreferenceamongplantpathogenicfungi.King,B.C.,Waxman,K.D.,Nenni,N.V.,Walker,L.P.,Bergstrom,G.C.&Gibson,D.M.(2011).BiotechnolBiofuels,4(4).LinktoArticleReadAbstractBackground:Thediscoveryanddevelopmentofnovelplantcellwalldegradingenzymesisakeysteptowardsmoreefficientdepolymerizationofpolysaccharidestofermentablesugarsfortheproductionofliquidtransportationbiofuelsandotherbioproducts.TheindustrialfungusTrichodermareeseiisknowntobehighlycellulolyticandisamajorindustrialmicrobialsourceforcommercialcellulases,xylanasesandothercellwalldegradingenzymes.However,enzyme-ProspectingresearchcontinuestoidentifyopportunitiestoenhancetheactivityofT.reeseienzymepreparationsbysupplementingwithenzymaticdiversityfromothermicrobes.Thegoalofthisstudywastoevaluatetheenzymaticpotentialofabroadrangeofplantpathogenicandnon-pathogenicfungifortheirabilitytodegradeplantbiomassandisolatedpolysaccharides.Results:Large-scalescreeningidentifiedarangeofhydrolyticactivitiesamong348uniqueisolatesrepresenting156speciesofplantpathogenicandnon-pathogenicfungi.Hierarchicalclusteringwasusedtoidentifygroupsofspecieswithsimilarhydrolyticprofiles.Amongmoderatelyandhighlyactivespecies,plantpathogenicspecieswerefoundtobemoreactivethannon-pathogensonsixofeightsubstratestested,withnosignificantdifferenceseenontheothertwosubstrates.Amongthepathogenicfungi,greaterhydrolysiswasseenwhentheyweretestedonbiomassandhemicellulosederivedfromtheirhostplants(commelinoidmonocotordicot).AlthoughT.reeseihasahydrolyticprofilethatishighlyactiveoncelluloseandpretreatedbiomass,itwaslessactivethansomenaturalisolatesoffungiwhentestedonxylansanduntreatedbiomass.Conclusions:Severalhighlyactiveisolatesofplantpathogenicfungiwereidentified,particularlywhentestedonxylansanduntreatedbiomass.Therewerestatisticallysignificantpreferencesforbiomasstypereflectingthemonocotordicothostpreferenceofthepathogentested.Thesehighlyactivefungiarepromisingtargetsforidentificationandcharacterizationofnovelcellwalldegradingenzymesforindustrialapplications.AnovelThermophilicxylanasefromAchaetomiumsp.Xz-8withhighcatalyticefficiencyandapplicationpotentialsinthebrewingandotherindustries.Zhao,L.,Meng,K.,Shi,P.,Bai,Y.,Luo,H.,Huang,H.,Wang,Y.,Yang,P.&Yao,B.(2013).ProcessBiochemistry,48(12),1879-1885.LinktoArticleReadAbstractThermophilicxylanasesareofgreatinterestfortheirwideindustrialapplicationprospects.Hereweidentifiedathermophilicxylanase(XynC01)ofglycosidehydrolase(GH)family10inathermophilicfungalstrainAchaetomiumsp.Xz-8.ThededucedaminoacidsofXynC01showedthehighestidentityof≤52%toexperimentallyverifiedxylanases.XynC01wasfunctionallyexpressedinPichiapastoris,showedoptimalactivityatpH5.5and75°CwithstabilityoverabroadpHrange(pH4.0–10.0)andattemperaturesof55°Candbelow.XynC01hadthehighestcatalyticefficiency(kcat/Km,3710mL/s/mg)everreportedforallGH10xylanases,andwasresistanttoalltestedmetalionsandchemicalreagents.Itshydrolysisproductsofvariousxylansweresimple,mainlyconsistingofxylobioseandxylose.Undersimulatedmashingconditions,XynC01alonehadacomparableeffectonfiltrationimprovementwithUltraflofromNovozymes(20.24%vs.20.71%),andshowedbetterperformancewhencombinedwithacommercialβ-glucanase(38.50%).Combiningallexcellentpropertiesdescribedabove,XynC01mayfinddiverseapplicationsinindustrialfields,especiallyinthebrewingindustry.Plantpathogensasasourceofdiverseenzymesforlignocellulosedigestion.Gibson,D.M.,King,B.C.,Hayes,M.L.&Bergstrom,G.C.(2011).CurrentOpinioninMicroBIOLOGy,14(3),264-270.LinktoArticleReadAbstractTheplantcellwallisamajorbarrierthatmanyplantpathogensmustsurmountforsuccessfulinvasionoftheirplanthosts.Fullgenomesequencingofanumberofplantpathogenshasrevealedoftenlarge,complex,andredundantenzymesystemsfordegradationofplantcellwalls.Recentsurveyshavenotedthatplantpathogenicfungiarehighlycompetentproducersoflignocellulolyticenzymes,andtheirenzymeactivitypatternsreflecthostspecificity.Weproposethatplantpathogensmaycontributetobiofuelproductionasdiversesourcesofaccessoryenzymesformoreefficientconversionoflignocelluloseintofermentablesugars.Roleof(1,3)(1,4)β-glucanincellwalls:Interactionwithcellulose.Kiemle,S.N.,Zhang,X.,Esker,A.R.,Toriz,G.,Gatenholm,P.&Cosgrove,D.J.(2014).Biomacromolecules,15(5),1727-1736.LinktoArticleReadAbstract(1,3)(1,4)-β-D-Glucan(mixed-linkageglucanorMLG),acharacteristichemicelluloseinprimarycellwallsofgrasses,wasinvestigatedtodeterminebothitsroleincellwallsanditsinteractionwithcelluloseandothercellwallpolysaccharidesinvitro.BindingisothermsshowedthatMLGadsorptionontomicrocrystallinecelluloseisslow,irreversible,andtemperature-dependent.MeasurementsusingquartzcrystalmicrobalancewithdissipationmonitoringshowedthatMLGadsorbedirreversiblyontoamorphousregeneratedcellulose,formingathickhydrogel.Oligosaccharideprofilingusingendo-(1,3)(1,4)-β-glucanaseindicatedthattherewasnodifferenceinthefrequencyanddistributionof(1,3)and(1,4)linksinboundandunboundMLG.ThebindingofMLGtocellulosewasreducedifthecellulosesampleswerefirsttreatedwithcertaincellwallpolysaccharides,suchasxyloglucanandglucuronoarabinoxylan.ThetetheringfunctionofMLGincellwallswastestedbyapplyingendo-(1,3)(1,4)-β-glucanasetowallsamplesinaconstantforceextensometer.Cellwallextensionwasnotinduced,whichindicatesthatenzyme-accessibleMLGdoesnottethercellulosefibrilsintoaload-bearingnetwork.Adsorptionofβ-glucosidasesintwocommercialpreparationsontopretreatedbiomassandlignin.Haven,M.Ø.&Jørgensen,H.(2013).BiotechnologyforBiofuels,6(1),165.LinktoArticleReadAbstractBackground:Enzymerecyclingisamethodtoreducetheproductioncostsforadvancedbioethanolbyloweringtheoveralluseofenzymes.Commercialcellulasepreparationsconsistofmanydifferentenzymesthatareimportantforefficientandcompletecellulose(andhemicellulose)hydrolysis.Thisabundanceofdifferentactivitiescomplicatesenzymerecyclingsincetheindividualenzymesbehavedifferentlyintheprocess.Previously,thegeneralperceptionwasthatβ-glucosidasescouldeasilyberecycledviatheliquidphase,astheyhavemostlybeenobservednottoadsorbtopretreatedbiomassoronlyadsorbtoaminorextent.Results:TheresultsfromthisstudywithCellic®CTec2revealedthatthevastmajorityoftheβ-glucosidaseactivitywaslostfromtheliquidphaseandwasadsorbedtotheresidualbiomassduringhydrolysisandfermentation.Adsorptionstudieswithβ-glucosidasesintwocommercialpreparations(Novozym188andCellic®CTec2)tosubstratesmimickingthecomponentsinpretreatedwheatstrawrevealedthattheAspergillusnigerβ-glucosidaseinNovozym188didnotadsorbsignificantlytoanyofthecomponentsinpretreatedwheatstraw,whereastheβ-glucosidaseinCellic®CTec2adsorbedstronglytolignin.Theextentofadsorptionofβ-glucosidasefromCellic®CTec2wasaffectedbybothtypeofbiomassandpretreatmentmethod.Withapproximately65%oftheβ-glucosidasesfromCellic®CTec2adsorbedontoligninfrompretreatedwheatstraw,theactivityoftheβ-glucosidasesintheslurrydecreasedbyonly15%.Thisdemonstratedthatsomeenzymeremainedactivedespitebeingbound.ItwaspossibletoreducetheadsorptionofCellic®CTec2β-glucosidasetoligninfrompretreatedwheatstrawbyadditionofbovineserumalbuminorpoly(ethyleneglycol).Conclusions:Contrarytotheβ-glucosidasesinNovozym188,theβ-glucosidasesinCellic®CTec2adsorbsignificantlytolignin.TheligninadsorptionobservedforCellic®CTec2isusuallynotaproblemduringhydrolysisandfermentationsincemostofthecatalyticactivityisretained.However,adsorptionofβ-glucosidasestoligninmayprovetobeaproblemwhentryingtorecycleenzymesintheproductionofadvancedbioethanol.

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