Oxford Genetics/pSFT7LacONH2PelBV53C (OG4550)/OG4550/1 Ea

PlasmidInfo:

PlasmidPurpose:

ThisplasmidisdesignedtoexpresstaggedproteinsinE.coli.ItcontainstheT7promoterthatcanberegulatedusingtheLacrepressor.ThisallowsforgreatercontroloverexpressionincomparisontonormalT7promoterplasmids.InordertousethisplasmidyouwillrequireaT7polymeraseexpressingE.colicelllinethatalsoexpressestheLacIrepressor.AcommonexpressioncelllinethatcanbeusedforthispurposeistheBL21(DE3)strain.

AbouttheCleavageTag:

Thisplasmidalsoencodesaproteasecleavagesitethatisdesignedtobepositionedbetweenyourgeneofinterestandthetagtoallowtheremovalofthetagfollowingproteinpurificationorisolation.Thisplasmidcontainsa3Ccleavagetag.Theproteinsequenceofthecleavagetagis:LEVLFQ?GP.HumanRhinovirus(HRV)3CProteaseisahighlyspecificproteasethatcleavesbetweentheGluandGlyresiduesofitsrecognitionsite.ItisoftenproducedwiththetrademnamePreScissionprotease.

Formoreinformationonwhichcleavagetagtouseseeourcleavagetagguide.

PromoterExpressionLevel:

ThisplasmidcontainstheIPTGinduciblepromoterthatwascreatedbythefusionoftheLacpromoterandtheTryptophanoperonpromoter.ItallowsinducibleexpressioninE.coliusingIPTGastheinducingagent.

AboutthePeptideTag:

ThisplasmidcontainsanPectateLyaseB(PelB)secretorysignalpeptide(SP)toallowproteinstobeexportedfromthecytosol.Duringtranslocationfromthecytosolthesignalpeptideisremovedfromtheproteinbyendogenousproteases.

ThisplasmidalsocontainsasecondaryV5proteintag.Thesequenceofthistagis:GKPIPNPLLGLDST

Weprovidearangeofdualpeptidetagplasmids.Thisisbecausesomepeptidetagsprovidespecificbiologicalproperties(e.gsmallmoleculeaffinitynewepitopessolubilityorproteinsecretion)thatarenotprovidedbyothers.

SequenceandMap:

OtherInfo:

TranscriptionTermination:

ThisplasmidcontainsthreealternativetranscriptionterminatorsforTagT7LacOInduciblebacterialandbacteriophage(T7)expression.Thismeansthatonlythepromoterneedstobechangedtoaltertheexpressionsystemyouareusing.Wesellmultiplepromotersthatcanbeusedineachofthesesystems.Thepresenceofeachterminatordoesnotreduceexpressioninthealternativesystems.

Cloning:

MakingProteinFusions:

ThisplasmidhasbeendesignedtoallowthreetypesofcloningintothemainMCStojoinacodingsequencewiththetag.

CloninginaGene:

Thisplasmidhasbeendesignedtobecompatiblewitharangeofcloningtechniques.Themultiplecloningsitecontainsarangeofstandardcommonlyusedrestrictionsitesforcloning.UsingthesesitesgenescanbeinsertedusingstandardcloningmethodswithDNAligase.Othermethodssuchasligaseindependentcloning(LIC)GibsonAssemblyInFusionHDorSeamlessGeneArtcanalsobeusedandbecauseallofourplasmidsarebasedonthesamebackbonethesamemethodcanbeusedforcloningintoallofourcataloguevectors.

Multiplecloningsitenotes:

ThereareafewimportantsiteswithintheMCS.TheseincludetheNcoIsitetheXbaIsiteandtheBsgIandBseRIsites.TheNcoIsitecontainsastartcodonthatisimmediatelydownstreamofbothaKozakandShine-Dalgarnoribosomalbindingsite.Theseallowforoptimalpositioningofgeneswhenthestartcodonisplacedinthislocation.IfthisisnotrequiredandyouwishtouseadownstreamsiteforgenecloningyoucanremovetheNcoIsitebycleavingtheplasmidwithKpnI.

TheXbaIsitecontainsastopcodon.ThisstopcodonispositionedinaspecificpositioninrelationtotheBsgIandBseRIsitesthatareimmediatelydownstream.WheneitherBseRIorBsgIcleavetheplasmidtheyproduceaTAoverhangfromthestopcodonintheXbaIsitethatiscompatiblewithallofourpeptidetagplasmidscutwiththesamesites.BseRIandBsgIsitesarenon-palindromicandcleaveadefinednumberofbasesawayfromtheirbindingsite.

WheneverwecloneageneintoourmultiplecloningsitewealwayspositionthestartandstopcodoninthesamepositionsintheMCS.IfthestartandendsofthegenesarenotcompatiblewithNcoIandXbaIweextendthesequencetothenearestexternalsitesbutkeepthestartandstopcodonslocationsconsistent.

1:SnapFusionCloning:

IfyouwouldliketofuseyourcodingsequencetothetagwithminimaladditionalbasesyoucanuseourSnapFusiontechnology.ThisprocessinvolvesamplifyingyourgenebyPCRtoaddspecificrestrictionsitesontotheends.WhenthesesitesarecuttheyproduceanoverhangthatiscompatiblewiththisplasmidcutwithBseRIorBsgI.

Toinsertyourgene:

1:Amplifyyourgenewithprimersdesignedusingthisspreadsheet
2:CuttheplasmidwitheitherBseRIorBsgI.*
3:Cutyourgenewiththeenzymeyouaddedusingthespreadsheet(anyofAcuIBpmIBpuEIBseRIBsgIEciI).
4:ClonethegeneintotheplasmidusingDNAligase.

UsingthismethodwithanN-terminaltagplasmidwillresultinthetagcodingsequenceimmediatelyfollowedbyyourgenesATGstartcodonatthejoin.Thisresultsinaseamlessfusionofthetwosequenceswithnoextrabasesbeingadded.UsingthismethodonC-terminaltagplasmidswillconvertyourgenesstopcodonintoaTAC(TyrY)codonfollowedbytheplasmidtagcodingsequence.Thisresultsinnoextrabasesbetweenyourgeneandthetag.Seethediagrambelowformoreinformation.

*PleasenotethatinsectexpressionplasmidscannotbecutwithBsgIonlyBseRIbecauseofunavoidableconflictingsitesinthebackbone.AlsoYeastplasmidscannotbecutwithBseRIbecauseofunavoidablerestrictionsitesinthebackbone.

Usingthistechniquewillcreateagenefragmentthatcanbeligatedintoanyorour>1500peptideandreportertagplasmids.Ifyouuseoneoftheothertechniquesbelow(GibsonInFusionSeamlessorLIC)youwillneednewprimersforeveryvectoryoucloneintobecausethearmsofhomologywillchangeaccordingtothetagplasmidyouarecloninginto.

Ifyoufindthatyourgenesequencehassitesinitthatmakeusingthiscloningstrategydifficultyoucanstilluseoneofthealternativemethodsbelow(e.g.standardcloningorGibsoncloning).

OpenthePrimerDesignTooltohelpyoudesignprimersforcloningyourgeneinourSnapFusiontechnique.

2:StandardEnzymes:

Ifyouarenotconcernedaboutleavingafewextrabasesbetweenthetagcodingsequenceandyourgeneyoucancloneyourgeneintothevectorusingstandardcloningrestrictionenzymes.Thisstrategywillrequireyoutochoosewhichenzymesyouwanttousetocloneyourgene.

OpenthePrimerDesignToolwhichprovidesprimerswithdifferentenzymechoicespositioningyourgeneasclosetothetagaspossibleineachcase.Pleasenotethatstandardenzymeswillalwaysleaveadditionalnucleotidesbetweenyourgeneandthetagbutusingthespreadsheetwillensurethetagandgeneareinframe.

3:Gibsoncloning/InfusionHD/GeneArtSeamless/LigaseIndependentCloning(LIC)Methods:

ThesecloningtechniquesusereagentssoldbyothercompaniesandallowyoutofusesequencestogetherusingenzymesthatchewbacktheDNAtoleaveoverlappingends/overhangs.ThesubsequentmethodofjoiningtheDNAdependsonthekitused.Touseoneofthesetechniquesyoucaneitherdesignyourownprimersoryoucanusethespreadsheetbelowtohelpwiththedesign.

OpenthePrimerDesignTooltohelpyoudesignprimersforcloningyourgeneusingGibsonassemblyInfusionHDGeneArtSeamlesscloningorLigaseIndependentCloning(LIC)techniques.

IPStatus:

IntellectualPropertyStatus

ThisproductispartofourSnapFastplasmidrange,formoreinformationontheIntellectualpropertystatusofthisplasmidpleaseclickhere