TheD-Mannose/D-Fructose/D-GlucosetestkitissuitableforthespecificmeasurementandanalysisofD-mannose,D-fructoseandD-glucoseinplantproductsandinacidhydrolysatesofpolysaccharides.Alteredphysiologyandbiochemistryofimportedlitchifruitheldunderdifferentvaporpressuredeficits.Somboonkaew,N.&Terry,L.A.(2010).JournalofAgriculturalandFoodChemistry,58(10),6209-6218.LinktoArticleReadAbstractTheeffectsofvaporpressuredeficit(VPD)onlitchifruitqualityhavenotyetbeenfullydefined.Theaimofthisstudywastodetailthechangesinphysiology,sugars,organicacids,andindividualanthocyaninconcentrationsinimportedlitchifruitheldatvariouscontrolledrelativehumidity(RH)andVPDlevels.SO2-fumigated(butnotacid-treated)litchiimportedfromThailand(cv.Kom)andfromIsrael(cv.Mauritius)wereairfreightedtotheUnitedKingdomandthenstoredfor9daysateither5or13°Ctosimulateshelf-lifeconditions.FruitswerestoredunderaseriesofcontrolledRHconditionsforthedurationofthetrialusingdifferentconcentrationsofglycerolindeonizedwater.Respirationratesandweightlossesofbothfruitlotsweregreaterinlitchistoredat13°CandaVPDof0.274kPa.At5°CandaVPDof0or0.042kPa,sugarsandorganicacidsinarilandpericarptissueandindividualanthocyaninsinpericarpwerebettermaintained.ThisisthefirstpieceofworkthathassystematicallyevaluatedtheeffectofaseriesofVPDsonlitchifruitbiochemistrysuchthatimplicationsfordesigningsystemstobettermaintainthephysiologicalqualityofimportedlitchifruitarediscussed.AnewbacterialhydrolasespecificforthecompatIBLesolutesα-D-mannopyranosyl-(1→2)-D-glycerateandα-D-glucopyranosyl-(1→2)-D-glycerate.Alarico,S.,EmpADInhas,N.&daCosta,M.S.(2013).EnzymeandMicrobialTechnology,52(2),77-83.LinktoArticleReadAbstractTheaccumulationpatternsandbiosynthesisofcompatiblesolutesinhyper/Thermophileshavebeenextensivelystudied.However,thereislittleinformationavailableontheirhydrolysis,leadingustosearchforenzymesforthisactivity.Fromtheanalysisofthegenomesofseveralmicroorganismsknowntoaccumulateα-D-mannopyranosyl-(1→2)-D-glycerate(mannosylglycerate,MG)orα-D-glucopyranosyl-(1→2)-D-glycerate(glucosylglycerate,GG)wewereabletoidentifyalikelycandidategeneforthehydrolysisofthesemolecules.TheThermusthermophilusHB27homologueencodedaputativeenzymewithmotifsoftheGH63andGH37familiesofglycosidehydrolases.WeexpressedthegenefromthisthermophilicbacteriumandfromRubrobacterradiotolerans,andconfirmedthattherecombinantenzymes,heredesignatedmannosylglyceratehydrolase(MgH),specificallyhydrolysedMG(orGG)tomannose(orglucose)andglycerate.Bothenzymeswerehighlystableandmaximallyactiveattemperaturesclosetoeachorganisms’optimalgrowthtemperatures(half-livesof15.4±0.5hat55°Cand16.1±0.4hat70°C)butatlowpH(4.0–4.5).CationswerenotrequiredfortheiractivityandeachenzymeexhibitedMichaelis–Mentenkineticsat50°Cand70°C,respectively,withcomparablecatalyticefficienciestowardsMGandGG.Herein,wepurifiedandcharacterizedanovelandhighlyspecificMG-andGG-hydrolyzingenzymethatrepresentanattractivetoolfordevelopmentofenzymaticassaysforquantificationofthesesolutes,whichseemtobemoreprevalentinmicroorganismsthaninitiallysUSPected.ThemolecularcharacterizationofanovelGH38α-mannosidasefromthecrenarchaeonSulfolobussolfataricusrevealeditsABIlityinde-mannosylatingglycoproteins.Cobucci-Ponzano,B.,Conte,F.,Strazzulli,A.,Capasso,C.,Fiume,I.,Pocsfalvi,G.,Rossi,M.&Moracci,M.(2010).Biochimie,92(12),1895-1907.LinktoArticleReadAbstractα-Mannosidases,importantenzymesintheN-glycanprocessinganddegradationinEukaryotes,arefrequentlyfoundinthegenomeofBacteriaandArchaeainwhichtheirfunctionisstilllargelyunknown.Theα-mannosidasefromthehyperthermophilicCrenarchaeonSulfolobussolfataricushasbeenidentifiedandpurifiedfromcellularextractsanditsgenehasbeenclonedandexpressedinEscherichiacoli.Thegene,belongingtoretainingGH38mannosidasesofthecarbohydrateactiveenzymeclassification,isabundantlyexpressedinthisArchaeon.Thepurifiedα-mannosidaseactivitydependsonasingleZn2+ionpersubunitisinhibitedbyswainsoninewithanIC50of0.2mM.Themolecularcharacterizationofthenativeandrecombinantenzyme,namedSsα-man,showedthatitishighlyspecificforα-mannosidesandα(1,2),α(1,3),andα(1,6)-D-mannobioses.Inaddition,theenzymeisabletodemannosylateMan3GlcNAc2andMan7GlcNAc2oligosaccharidescommonlyfoundinN-glycosylatedproteins.Moreinterestingly,Ssα-manremovesmannoseresiduesfromtheglycosidicmoietyofthebovinepancreaticribonucleaseB,suggestingthatitcouldprocessmannosylatedproteinsalsoinvivo.Thisisthefirstevidencethatarchaealglycosidasesareinvolvedinthedirectmodificationofglycoproteins.TheplantSelaginellamoellendorffiipossessesenzymesforsynthesisandhydrolysisofthecompatiblesolutesmannosylglycerateandglucosylglycerate.Nobre,A.,Empadinhas,N.,Nobre,M.F.,Lourenço,E.C.,Maycock,C.,Ventura,M.R.,MingoteA.&daCosta,M.S.(2013).Planta,237(3),891-901.LinktoArticleReadAbstractAmannosylglyceratesynthase(MgS)genedetectedinthegenomeofSelaginellamoellendorffiiwasexpressedinE.coliandtherecombinantenzymewaspurifiedandcharacterized.Aremarkableandunprecedentedfeatureofthisenzymewastheabilitytoefficientlysynthesizemannosylglycerate(MG)andglucosylglycerate(GG)alike,withmaximalactivityat50°C,pH8.0andwithMg2+asreactionenhancer.Wehavealsoidentifiedanovelglycosidehydrolasegeneinthisplant’sgenome,whichwasfunctionallyconfirmedtobehighlyspecificforthehydrolysisofMGandGGandnamedMGhydrolase(MgH),duetoitshomologywithbacterialMgHs.Therecombinantenzymewasmaximallyactiveat40°CandatpH6.0–6.5.Theactivitywasindependentofcations,butMn2+wasastrongstimulator.RegardlessoftheseefficientenzymaticresourceswecouldnotdetectMGorGGinS.moellendorffiiorintheextractsoffiveadditionalSelaginellaspecies.Herein,wedescribethepropertiesofthefirsteukaryoticenzymesforthesynthesisandhydrolysisofthecompatiblesolutes,MGandGG.Celllysisinducedbymembrane-damagingdetergentsaponinsfromQuillajasaponaria.Berlowska,J.,Dudkiewicz,M.,Kregiel,D.,Czyzowska,A.&Witonska,I.(2015).EnzymeandMicrobialTechnology,75,44-48.LinktoArticleReadAbstractThispaperpresentstheresultsofastudytodeterminetheeffectofQuillajasaponariasaponinsonthelysisofindustrialyeaststrains.CelllysisinducedbysaponinfromQ.saponariacombinedwiththeplasmolysingeffectof5%NaClforSaccharomycescerevisiae,Kluyveromycesmarxianusyeastsbiomasswasconductedat50°Cfor24–48 h.Membranepermeabilityandintegrityoftheyeastcellsweremonitoredusingfluorescenttechniquesandconcentrationsofproteins,freeaminonitrogen(FAN)andfreeaminoacidsinresultinglysateswereanalyzed.Proteinreleasewassignificantlyhigherinthecaseofyeastcelllysispromotedwith0.008%Q.saponariaand5%NaClincomparisontoplasmolysistriggeredbyNaClonly.Strategicoptimizationofxylanase–mannanasecombi-CLEAsforsynergisticandefficienthydrolysisofcomplexlignocellulosicsubstrates.Bhattacharya,A.&Pletschke,B.I.(2015).JournalofMolecularCatalysisB:Enzymatic,115,140-150.LinktoArticleReadAbstractCost-effectiveapplicationoflignocellulolyticenzymesholdsthekeytowardscommercializationofenzymatichydrolysisoflignocellulosicbiomass.Carrierfreeimmobilizationofenzyme(s)offersalucrativeProspect.Combined-crosslinkedenzymeaggregates(combi-CLEAs)areanovelprospectiveandthispresentstudyaddressesthepreparation,characterizationandapplicationofxylanase–mannanasecombi-CLEASonlime-preteatedsugarcanebagasseandmilledcornstover.X6-CLEAs,X7-CLEAs,L1-CLEAsandL7-CLEAswerepreparedafterelaborativeoptimizationoftheprecipitatingagentandglutaraldehydeconcentration.Thehighestactivityafterprecipitationwasobservedwithacetonebutfollowingcross-linkingwithglutaraldehydelessthan60%activitywasretained,whilemorethan60%activitywasretainedafterprecipitationwithammoniumsulphateandcross-linkingwithglutaraldehyde.Accessoryenzymeactivitiesincludingα-arabinofuranosidase,β-xylosidase,esterases,β-mannosidase,α-galactosidaseandβ-glucosidasewerealsodetermined.Morethanan1.5foldincreaseinthermostabilitycomparedtothefreeenzymewasobservedoverabroadtemperaturerange(50–70°C).Tri-synergystudiesandquadsynergystudieswereusedtogeneratecombi-CLEAswithdifferentproteinratios.Hydrolysisoflimepre-treatedbagassewithcombi-CLEAsatproteinratioscorrespondingtoX6(33.0%):X7(17.0%):L1(17.0%):L7(33.0%)resultedina1.68foldhighersugarreleasecomparedtothequadsynergymodelusingfreeenzymes.Similarly,hydrolysisofcornstoverwithcombi-CLEAsatproteinratioscorrespondingtoX6(40.0%):X7(10.0%):L1(10.0%):L7(40.0%)resultedinan1.58foldhighersugarreleasecomparedtothesugarreleaseobservedwiththequadsynergymodelusingfreeenzymes.Monomericsugarsconstituted70–75%ofreducingsugarsreleasedduringhydrolysis.Theroleofaccessoryenzymesinimprovingenzymesynergywasclearlyshown.Theefficiencyofcombi-CLEAscomparedtofreeenzymesmakesthemidealcandidatesfortheprudentandcost-effectivecommercializationoflignocellulolyticenzymes.ABacteroideteslocusdedicatedtofungal1,6-β-glucandegradation:uniquesubstrateconformationdrivesspecificityofthekeyendo-1,6-β-glucanase.Temple,M.J.,Cuskin,F.,Baslé,A.,Hickey,N.,Speciale,G.,Williams,S.J.,Gilbert,H.J.&Lowe,E.C.(2017).JournalofBIOLOGicalChemistry,jbc-M117.LinktoArticleReadAbstractGlycansaremajornutrientsavailabletothehumangutmicrobiota(HGM).TheBacteroidesaregeneralistglycandegradersandthisfunctionismediatedlargelybypolysaccharideutilizationloci(PULs).ThegenomesofseveralBacteroidesspeciescontainaPUL,PUL1,6-beta;-glucan,thatwaspredictedtotargetmixedlinkedplant1,3;1,4-beta-glucans.TotestthishypothesiswecharacterizedtheproteinsencodedbythislocusinBacteroidesthetaiotaomicron,amemberoftheHGM.WeshowherethatPUL1,6-β-glucandoesnotorchestratethedegradationofaplantpolysaccharidebuttargetsafungalcellwallglycan,1,6-beta-glucan,whichisagrowthsubstrateforthebacterium.Thelocusisupregulatedby1,6-beta-glucan,andencodestwoenzymes,asurfaceendo-1,6-beta-glucanase,BT3312,andaperiplasmicbeta-glucosidasethattargetsprimarily1,6-beta-glucans.Thenon-catalyticproteinsencodedbyPUL1,6-beta-glucantarget1,6-beta-glucansandcompriseasurfaceglycanbindingproteinandaSusDhomologuethatdeliversglycanstotheoutermembranetransporter.Weidentifiedthecentralroleoftheendo-1,6-beta-glucanasein1,6-beta-glucandepolymerizationbydeletingbt3312,whichpreventedthegrowthofB.thetaiotaomicronon1,6-beta-glucan.ThecrystalstructureofBT3312incomplexwithβ-glucosyl-1,6-deoxynojirimycin,revealedaTIMbarrelcatalyticdomainthatcontainsadeepsubstratebindingclefttailoredtoaccommodatethehook-likestructureadoptedby1,6-beta-glucan.Specificityisdrivenbythecomplementarityoftheenzymeactivesitecleftandtheconformationofthesubstrate.WealsonotedthatPUL1,6-beta-glucanissyntenictomanyPULsfromotherBacteroidetessuggestingthatutilizationofyeastandfungalcellwall1,6-beta-glucansisawidespreadadaptationwithinthehumanmicrobiota.Useofalmondshellasfoodingredient.Kacem,I.,Martinez-Saez,N.,Kallel,F.,Khawla,J.B.,Claire,H.B.,Semia,C.E.&delCastillo,M.D.(2017).EuropeanFoodResearchandTechnology,1-12.LinktoArticleReadAbstractAlmondshellisamajorwastefromthealmondprocessingindustry.Itsfeasibilityasnaturalsourceofhealth-promotingcomponentswasexamined.Theby-productwasfractionatedunderbasicconditionsfollowinganeasyscale-upprocess.Thechemicalcompositionoftherecoveredfractionanditsantioxidantandantidiabeticpropertieswereevaluated.Novelinformationregardingthechemicalcompositionofthepolysaccharideswasalsoobtained.Almondshellisformedbylignin-carbohydratecomplexespossessingantioxidantpropertiesandcapacitytoinhibitα-glucosidase.Accordingtoourknowledge,thisisthefirsttimeα-glucosidaseinhibitoryactivityofalignin-carbohydratecomplexisreported.Biscuitscontainingnon-caloricsweetenersoluble(2.5%)andinsoluble(5.6%)dietaryfiber,naturalantioxidants(1.34mgofgallicacidequivalents/g)andα-glucosidaseinhibitors(1gofbiscuit–1mgofacarbose)achievedahighsensorialscore(7.2outof9)whenalmondshellwasincorporatedtothem.Theapplicationofafractionfromalmondshellcontaininglignin-polysaccharidescomplexesasfoodingredientinbiscuitformulationsforpeoplewithparticularnutritionalrequirementsisfeasibleandnew.UV-methodforthedeterminationofD-Mannose,D-FructoseandD-Glucoseinfoodstuffs,yeastcellpreparationsandothermaterialsPrinciple:                                 (hexokinase)(1)D-Mannose/D-fructose/D-glucose+ATP→                              M-6-P/F-6-P/G-6-P+ADP   (glucose-6-phosphatedehydrogenase)(2)G-6-P+NADP+→gluconate-6-phosphate+NADPH+H+  (phosphomannoseisomerase)(phosphoglucoseisomerase)(3) M-6-P       ↔       F-6-P       ↔       G-6-PKitsize:                          *55assays* Thenumberofmanualtestsperkitcanbedoubledifallvolumesarehalved. ThiscanbereadilyaccommodatedusingtheMegaQuantTM WaveSpectrophotometer(D-MQWAVE).Method:                          Spectrophotometricat340nmReactiontime:                 ~30minDetectionlimit:                0.7mg/LApplicationexamples:Foodstuffs,yeastcellpreparations,enzymatichydrolysatesandothermaterials(e.g.biologicalcultures,samples,etc.)Methodrecognition:       NovelmethodAdvantagesVerycompetitiveprice(costpertest) Allreagentsstablefor>2yearsafterpreparation Onlyenzymatickitavailable Simpleformat Rapidreaction Mega-Calc™softwaretoolisavailablefromourwebsiteforhassle-freerawdataprocessing Standardincluded

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