Description: Anoptimizedblendofa
Thermo stableDNALigaseandaproprietaryadditive,HiFi
Taq DNALigaseefficientlysealsnicksinDNAwithunmatchedhighfidelity.Theformationofaphosphodiesterbondbetweenjuxtaposed5´phosphateand3´hydroxylterminioftwoadjacentoligonucleotidesthatarehybridizedtoacomplementarytargetDNAisenhancedintheimprovedreactionbufferandmismatchligationisdramaticallyreduced(1).Theimprovedformulationallowshigherresolutiondiscriminationbetweenligationdonorsandacceptors,enablingprecisedetectionofSNPsandotherallelevariants.HiFi
Taq DNALigaseisactiveatelevatedtemperatures(37–75°C)(2,3).
PleasenotethatHiFiTaqDNALigaseisintendedforuseinmoleculardiagnosticsapplicationsthatdependonhighfidelitynickligation.ItisnotasubstituteforT4DNAligaseandisnotsuitableforcloningapplicationsoradapterligation/NGSlibraryprep.
Useouronlinetool,ThermostableLigaseReactionTemperatureCalculator,tohelpselectthecorrectincubationtemperatureforHiFiTaqDNALigase.
Figure1:HiFiTaq DNALigasedisplaysincreasedfidelity (A)Schematicofmultiplexedsubstratepools.EachsubstratepoolcontainedasinglesplintwithadefinedNNattheligationjunction(e.g.,AA,AC,AG…)alongwithallfourupstreamprobesandallfourFAM-labeleddownstreamprobes.Eachprobethatencodesthebaseattheligationjunctionisofuniquelengthallowingforseparationandanalysisbycapillaryelectrophoresis.Atotalof16substratepoolswereprepared,oneforeachuniquesplint.(B)ComparisonoftheligationfidelityofAmpligase(Epicentre),Taq DNALigaseandHiFiTaq DNALigase.Fidelitymeasurementswereperformedusing1μlofligaseina50μlreactionmixtureinthesuppliedbuffersat1Xconcentration.Reactionswereincubated30minat55°C,usingmultiplexedsubstratepoolsasoutlinedin(A).Rowsrepresentasingletemplatesequence,whilecolumnsindicateaparticularligationproductresultingfromaspecificpairofprobesligatingwiththeindicatedbasesattheligationjunction.Adotindicatesdetectionofaproduct(seelegendabove).ThediagonalfromthetoplefttothebottomrightrepresentsWatson-Crickligationproducts;allotherspacesindicatemismatchligationproducts.WhileTaq DNALigaseandAmpligaseperformsimilarlyundertheseconditions,witharangeofmismatchproductsdetectable,HiFiTaq DNALigaseshowsdramaticallyfewermismatchproductswhilemaintaininghighyields(imageadaptedfromReference1).Figure2:HiFiTaq DNALigaseexhibitsincreaseddiscriminationatbothsidesoftheligationjunction Oligonucleotideprobestargetinga35bpregionoftheλintegrasegenewereincubatedwith16.7fmolofλgenomicDNA.LigationproductsformedweredetectedbyqPCRusingSYBR ®Green.HiFiTaq DNALigase(NEB #M0647)displaysincreasedfidelityoverTaq DNALigase(NEB#M0208)andAmpligase,showingalargerΔCtvaluebetweenprobesfullycomplementarytothetargetsequenceandthosewithamismatchedbasepairattheligationjunction.Figure3:HiFiTaq DNALigaseexhibitsincreasedthermostABI lity HiFiTaq DNALigaseandAmpligase®(1µlenzymeina50µlreaction)werecycled(80°Cfor90seconds/94°Cfor10 seconds)upto100 timesintheirrespective1Xreactionbuffer.LigaseactivitywasassayedusingaFAM-labelednickeddsDNAsubstratedetectedbycapillaryelectrophoresis.Figure4:HiFiTaq DNALigasedisplays2-foldreductioninmismatchligationascomparedtoAmpligase TheC:GWatson-Crickbasepairbetweentheupstreamprobe3´-terminalbaseandthecomplementarystrandmakesthisaparticularlydifficultjunctionforaligasetodiscriminateagainstmismatchligationproducts(1).ProductSource Purifiedfroman
E.coli strainthatcarriestheclonedligasegenefromahyperthermophilicorganism.
ReagentsSupplied Thefollowingreagentsaresuppliedwiththisproduct:
Storeat(°C) Concentration HiFiTaq DNALigaseReactionBuffer -20 10X
Notes: ReactionConditions:ReactionswithHiFiTaqDNALigaseshouldbeperformedbetween37–75°C.Theoptimalligationincubationtemperatureforagivensetofprobesistypicallywithin5°CoftheTmoftheprobesannealingregionandmustbedeterminedempiricallyforthebestbalanceofactivityandfidelityinyourapplication.Useofthe ThermostableLigaseReactionTempCalculatorishighlyrecommendedforselectionofanincubationtemperature.ForatypicalLDR-typeassay,reactiontimeshouldbeintherangeof10–60minutes,with15minutesbeingidealformanyapplications.Forassaysrequiringdenaturation/annealing/ligationcycling,wesuggestdenaturation@95°Cfor30s–1min,followedbyannealing/ligationfor1–5minattheoptimizedligationtemperatureforyourprobeset.1XHiFiTaqDNALigaseReactionBufferrequiresNAD+asacofactor.NAD+issuppliedinthe10XHiFiTaqDNALigaseReactionBuffer.While10XHiFiTaqDNALigaseBufferisstableat-20°Cfor3years,thebuffershouldbestoredat-80°Ctofurtherextendthehalf-lifeoftheNAD+cofactor.TodiluteHiFiTaqDNALigasethatwillsubsequentlybestoredat-20°C,50%glycerolstoragebuffer(DiluentBufferA,NEB#B8001)canbeused,however,theshelflifeofHiFiTaqDNALigasedilutedinthisbufferwillbereduced.Todiluteforimmediateuse,1XHiFiTaqDNALigaseReactionBuffercanbeused.Inordertoachievethehighestfidelityposs
IBL ewithHiFiTaqDNALigase,werecommendusingHiFiTaqDNALigaseReactionBuffer,however,HiFiTaqDNALigasecanbeusedinTaqDNALigaseReactionBufferwithreducedactivityandfidelity.Conversely,theuseofstandardTaqDNALigaseinHiFiTaqDNALigaseReactionBufferwillboostthefidelityofthatenzyme.HiFiTaqDNALigasecanbeusedinavarietyofpolymerasebufferswhensupplementedwith1mMNADwithreducedactivityandmodestlyreducedfidelity.Whenvisualizingligationreactionsbygel,someDNAsequencesmayexhibitagelshiftduetobindingofproteincomponents.Thisproteinbindingdoesnotinterferewithmostdownstreammethodsincludingamplification.Werecommendpre-treatmentwithProteinaseK(1μlinatypical50μlligationreaction)for30minat37°Cbeforelo
ADI ngonageltoremovethisshift.Themolarconcentrationoftheligaseis44nM.