感受态细胞种类比较

名称Genetype特点用途说明DH5αF-endA1glnV44thi-1recA1relA1gyrA96deoRnupGΦ80dlacZΔM15Δ（lacZYA-argF）U169,hsdR17（rK-,λ-）种常用于质粒克隆的菌株。其Φ80dlacZΔM15基因的表达产物与pUC载体编码的β-半乳糖苷酶氨基端实现α互补，可用于蓝白斑筛选。recA1和endA1的突变有利于克隆DNA的稳定和高纯度质粒DNA的提取。分子克隆、质粒提取和蛋白质表达。JM109endA1glnV44thi-1relA1gyrA96recA1mcrB+Δ（lac-proAB）e14-[F'traD36proAB+lacIqlacZΔM15]hsdR17（rK-mK+）。部分抗性缺陷，适合重复基因表达，可用于M13克隆序列测定和蓝白斑筛选。分子克隆、质粒提取和蛋白质表达。BL21（DE3）F-ompTgaldcmlonhsdSB（rB-mB-）λ（DE3[lacIlacUV5-T7gene1ind1sam7nin5）该菌株用于以T7RNA聚合酶为表达系统的高效外源基因的蛋白表达宿主。T7噬菌体RNA聚合酶基因的表达受控于λ噬菌体DE3区的lacUV5启动子，该区整合于BL21的染色体上。该菌适合于非毒性蛋白的表达。蛋白质表达。BL21（DE3）plysSF-ompTgaldcmlonhsdSB（rB-mB-）λ（DE3）pLysS（cmR）该菌株带有pLysS,具有氯霉素抗性。此质粒还有表达T7溶菌酶的基因，T7溶菌酶能够降低目的基因的背景表达水平，但不干扰IPTG诱导的表达。适合于毒性蛋白和非毒性蛋白的表达。蛋白质表达BL21StarTM(DE3):F-ompThsdSB(rB-mB-)galdcmrne131(DE3)Thetwostrainscarryamutatedrnegene(rne131)whichencodesatruncatedRNaseEenzymethatlackstheabilitytodegrademRNA,resultinginanincreaseinmRNAstability.ThetwostrainsareE.coliB/rstrainsanddonotcontainthelonprotease.Theyarealsodeficientintheoutermembraneprotease,OmpT.ThelackoftheseproteasesreducesdegradationofheterologousproteinsexpressedinExpressingHeterologousGenesBL21StarTM(DE3)pLysS:F-ompThsdSB(rB-mB-)galdcmrne131(DE3)pLysS(CamR)thestrains.BL21Star(DE3)pLysScarriesthepLysSplasmidwhichproducesT7lysozyme(seepage1).TheBL21Star(DE3)straindoesnotcarryaplasmidexpressingT7lysozyme.RosettaTM2CompetentCellsF-ompThsdSB(rB-MB-)galdcmpRARE2(CamR)Rosetta™2hoststrainsareBL21derivativesdesignedtoenhancetheexpressionofeukaryoticproteinsthatcontaincodonsrarelyusedinE.coli.ThesestrainssupplytRNAsfor7rarecodones(AGA,AGG,AUA,CUA,GGA,CCC,andCGG)onacompatiblechloramphenicol-resistantplasmid.ThetRNAgenesaredrivenbytheirnativepromoters.用于真核蛋白表达（表达稀有密码子）