E.coli genotypes 大肠杆菌基因型手册

大肠杆菌基因型及遗传符号说明系列一点击次数：982 作者：佚名发表于：2009-09-27 00:00转载请注明来自丁香园来源：丁香园实验室的一般大肠杆菌拥有4288条基因，每条基因的长度约为950bp,基因间的平均间隔为118bp （基因Ⅷ）。

E.coli基因组中还包含有许多插入序列，如λ-噬菌体片段和一些其他特殊组份的片段，这些插入的片段都是由基因的水平转移和基因重组而形成的，由此表明了基因组具有它的可塑造性。

利用大肠杆菌基因组的这种特性对其进行改造，使其中的某些基因发生突变或缺失，从而给大肠杆菌带来可以观察到的变化，这种能观察到的特征叫做大肠杆菌的表现型（Phenotype），把引起这种变化的基因构成叫做大肠杆菌的基因型（Genotype）。

具有不同基因型的菌株表现出不同的特性。

分子克隆中常用的大肠杆菌及其遗传标记按Demerec等1966年提出的命名原则，采用的菌株所有的基因都假定处于野生型状态，除非在基因型上另外注明。

大肠杆菌基因型的表示方法（Demerec, et, al. 1966）：一、一般规则：1、根据基因产物或其作用产物的英文名称的第一个字母缩写成3个小写斜体字母来表示。

例如：D NA Adenine Methylase→dam。

2、不同的基因座，其中任何一个突变所产生的表型变化可能相同，其表示方法是在3个小写斜体字母后加上一个斜体大写字母来表示区别。

例如：Recombination→recA、recB、recC。

3、突变位点应通过在突变基因符号后加不同数字表示。

如supE44（sup基因座E的44位突变）。

如果不知道几个等位基因中哪一/几个发生了功能性突变，则用连字符“ -”代替大写字母，如trp-31。

4、细菌的基因型中应该包含关于其携带的质粒或附加体的的信息。

这些符号包括菌株携带的质粒或附加体、质粒或附加体上的突变基因座和突变位点。

其基因符号应与基因座的表示符号明显区别，符号的第一个字母大写、不斜体并位于括号内；质粒或附加体上的突变基因座和突变位点的基因符号的表示方法与染色体上突变基因座、突变位点的符号相同。

大肠杆菌的genotype说明，看懂大肠杆菌菌株的genotype 总结了一些关于大肠杆菌基因型的资料，和大家分享一下。

大肠杆菌基因型说明hsdR 有利于非甲基化DNA（如PCR扩增产物）的有效转化。

mcrA 有利于甲基化DNA（如基因组）的有效转化。

acZΔM15 用于蓝白斑筛选。

endA1 无Endonuclease I 酶活性，有利于质粒的纯化。

recA1 减少克隆DNA的非特异性重组。

DE3 编码T7 RNA聚合酶，用于诱导T7-启动的表达系统的表达。

DeoR 可以高效吸收大片段DNA，有利于文库的构建。

Tn10 含有四环素抗性的转座子。

OmpT 表明大肠杆菌缺乏外膜蛋白酶。

缺乏外膜蛋白酶的菌株可以降低表达的外源蛋白在细菌中被降解的程度，有利于获得完整的重组蛋白。

PLys 含编码T7溶菌酶的质粒；通过抑制T7 RNA聚合酶基础表达水平来降低T7启动的表达体系的基础表达水平。

ArgF 由于突变细菌不能利用arginine。

F’一个低拷贝可移动的质粒，当被M13噬菌体侵染时，可产生单链DNA。

LacI 编码lac抑制子，用于蓝白斑筛选时需加入IPTG，才可启动表达β-gal。

dam/dcm 消除了内源腺苷和鸟苷的甲基化。

在此种细菌中繁殖的DNA不被甲基化F-，F 因子缺失φ80dlacZΔM15，lacZDM15（Lactose）Map position：8 min 功能：lacZM15是表达β-半乳糖苷酶α片断的一段基因，当M15缺失（△M15）时，lacZ基因虽然能表达ω片断，但不能表达α片断，β- 半乳糖苷酶没有活性。

当带有lacZ（α片断）基因的lac操纵子通过载体DNA（如pUC19 DNA）转化到lacZ△M15基因型的细胞(如E.coli JM109）时，在有IPTG (异丙基-β-D-1-硫代半乳糖苷) 存在的情况下, β-半乳糖苷酶表现出活性,它能分解X-gal (半乳糖类似物)，使其呈现蓝色。

大肠杆菌（E.coli）酶联免疫分析试剂盒使用说明书本试剂盒仅供研究使用。

检测范围：96T6ng/L - 220ng/L使用目的：本试剂盒用于测定血清、血浆及相关液体样本中大肠杆菌（E.coli）含量。

实验原理本试剂盒应用双抗体夹心法测定标本中大肠杆菌（E.coli）水平。

用纯化的大肠杆菌（E.coli）抗体包被微孔板，制成固相抗体，往包被单抗的微孔中依次加入大肠杆菌（E.coli），再与HRP标记的大肠杆菌（E.coli）抗体结合，形成抗体-抗原-酶标抗体复合物，经过彻底洗涤后加底物TMB显色。

TMB在HRP酶的催化下转化成蓝色，并在酸的作用下转化成最终的黄色。

颜色的深浅和样品中的大肠杆菌（E.coli）呈正相关。

用酶标仪在450nm波长下测定吸光度（OD值），通过标准曲线计算样品中大肠杆菌（E.coli）浓度。

试剂盒组成标本要求1．标本采集后尽早进行提取，提取按相关文献进行，提取后应尽快进行实验。

若不能马上进行试验，可将标本放于-20℃保存，但应避免反复冻融2．不能检测含NaN3的样品，因NaN3抑制辣根过氧化物酶的（HRP）活性。

操作步骤1.标准品的稀释：本试剂盒提供原倍标准品一支，用户可按照下列图表在小试管中进行稀2.加样：分别设空白孔（空白对照孔不加样品及酶标试剂，其余各步操作相同）、标准孔、待测样品孔。

在酶标包被板上标准品准确加样50μl，待测样品孔中先加样品稀释液40μl，然后再加待测样品10μl（样品最终稀释度为5倍）。

加样将样品加于酶标板孔底部，尽量不触及孔壁，轻轻晃动混匀。

3.温育：用封板膜封板后置37℃温育30分钟。

4.配液：将30倍浓缩洗涤液用蒸馏水30倍稀释后备用5.洗涤：小心揭掉封板膜，弃去液体，甩干，每孔加满洗涤液，静置30秒后弃去，如此重复5次，拍干。

6.加酶：每孔加入酶标试剂50μl，空白孔除外。

7.温育：操作同3。

8.洗涤：操作同5。

9.显色：每孔先加入显色剂A50μl，再加入显色剂B50μl，轻轻震荡混匀，37℃避光显色15分钟.10.终止：每孔加终止液50μl，终止反应（此时蓝色立转黄色）。

大肠杆菌毒力基因转录组概述及解释说明引言部分内容如下：大肠杆菌（Escherichia coli）是一种常见的革兰氏阴性菌，广泛存在于自然界中。

虽然大肠杆菌通常被认为是人和动物的共生菌，但某些毒力菌株却可能引发严重的疾病。

这些毒力菌株携带着一系列的毒力基因，这些基因在细菌所致疾病的发展过程中发挥着重要作用。

本文旨在综述并解释大肠杆菌毒力基因及其转录组相关知识。

首先，我们将对大肠杆菌毒力基因进行定义、分类和作用机制等方面进行概述。

随后，我们将介绍大肠杆菌转录组研究的概念、原理以及相关方法与技术发展。

最后，我们将详细阐述转录组在大肠杆菌毒力基因研究中的作用和意义。

通过研究大肠杆菌转录组数据，我们可以揭示与毒力基因表达调控有关的网络和通路。

这有助于深入了解大肠杆菌所引发疾病的发病机制。

此外，转录组研究还能够预测和鉴定新的毒力基因候选者，为进一步的实验研究提供有价值的指导。

尤其值得一提的是，转录组研究对于开发相关的疫苗和治疗策略具有重要意义。

通过深入了解毒力基因及其调控机制，我们可以寻找到干扰这些机制的方法，为新型药物和防治策略的发展提供理论依据。

然而，虽然大肠杆菌转录组研究在毒力基因领域中具有巨大潜力，但目前仍面临着挑战与限制。

例如，在数据分析过程中可能存在一些技术问题和误差。

此外，对于大肠杆菌复杂生态系统中转录组网络整体功能的理解仍需进一步深入。

总之，通过综合分析与讨论大肠杆菌毒力基因与转录组相关内容，并探讨其作用和意义，旨在为更好地理解大肠杆菌致病机制以及开发相应治疗策略提供参考。

本文将总结当前的研究进展，并对大肠杆菌毒力基因转录组研究的未来发展方向进行展望，同时也探讨了该领域目前存在的挑战和限制。

2. 大肠杆菌毒力基因:2.1 毒力基因的定义与分类:大肠杆菌是一种广泛存在于自然界中的细菌，其中一部分菌株具有致病性。

致病性大肠杆菌通常通过其特定的毒力因子对宿主产生危害。

这些毒力因子被称为大肠杆菌毒力基因。

大肠杆菌（E.coli）酶联免疫分析试剂盒使用说明书本试剂盒仅供研究使用。

检测范围：96T6ng/L - 220ng/L使用目的：本试剂盒用于测定血清、血浆及相关液体样本中大肠杆菌（E.coli）含量。

实验原理本试剂盒应用双抗体夹心法测定标本中大肠杆菌（E.coli）水平。

用纯化的大肠杆菌（E.coli）抗体包被微孔板，制成固相抗体，往包被单抗的微孔中依次加入大肠杆菌（E.coli），再与HRP标记的大肠杆菌（E.coli）抗体结合，形成抗体-抗原-酶标抗体复合物，经过彻底洗涤后加底物TMB显色。

TMB在HRP酶的催化下转化成蓝色，并在酸的作用下转化成最终的黄色。

颜色的深浅和样品中的大肠杆菌（E.coli）呈正相关。

用酶标仪在450nm波长下测定吸光度（OD值），通过标准曲线计算样品中大肠杆菌（E.coli）浓度。

试剂盒组成标本要求1．标本采集后尽早进行提取，提取按相关文献进行，提取后应尽快进行实验。

若不能马上进行试验，可将标本放于-20℃保存，但应避免反复冻融2．不能检测含NaN3的样品，因NaN3抑制辣根过氧化物酶的（HRP）活性。

操作步骤1.标准品的稀释：本试剂盒提供原倍标准品一支，用户可按照下列图表在小试管中进行稀2.加样：分别设空白孔（空白对照孔不加样品及酶标试剂，其余各步操作相同）、标准孔、待测样品孔。

在酶标包被板上标准品准确加样50μl，待测样品孔中先加样品稀释液40μl，然后再加待测样品10μl（样品最终稀释度为5倍）。

加样将样品加于酶标板孔底部，尽量不触及孔壁，轻轻晃动混匀。

3.温育：用封板膜封板后置37℃温育30分钟。

4.配液：将30倍浓缩洗涤液用蒸馏水30倍稀释后备用5.洗涤：小心揭掉封板膜，弃去液体，甩干，每孔加满洗涤液，静置30秒后弃去，如此重复5次，拍干。

6.加酶：每孔加入酶标试剂50μl，空白孔除外。

7.温育：操作同3。

8.洗涤：操作同5。

9.显色：每孔先加入显色剂A50μl，再加入显色剂B50μl，轻轻震荡混匀，37℃避光显色15分钟.10.终止：每孔加终止液50μl，终止反应（此时蓝色立转黄色）。

Commonly used strains /wiki/E._coli_genotypes 1.AG1endA1 recA1 gyrA96 thi-1 relA1 glnV44 hsdR17(rK - mK+)2.AB1157thr-1, araC14, leuB6(Am), Δ(gpt-proA)62, lacY1, tsx-33, qsr'-0,glnV44(AS), galK2(Oc), LAM-, Rac-0, hisG4(Oc), rfbC1, mgl-51,rpoS396(Am), rpsL31(strR), kdgK51, xylA5, mtl-1, argE3(Oc), thi-1∙Bachmann BJ: Derivation and genotypes of some mutant derivatives of Escherichia coli K-12.Escherichia coli and Salmonella typhimurium. Cellular and Molecular Biology (Edited by: F C Neidhardt J L Ingraham KB Low B Magasanik M Schaechter H E Umbarger). Washington, D.C., American Society for Microbiology 1987, 2:1190-1219.See CGSC#11573.BL21E. coli B F- dcm ompT hsdS(rB - mB-) gal [malB+]K-12(λS)∙The "malB region" was transduced in from the K-12 strain W3110 to make the strain Mal+λS. See Studier et al. (2009) J. Mol. Biol.394(4), 653 for a discussion of the extent of the transfer.∙Stratagene E. coli Genotype Strains4.BL21(AI)F– ompT gal dcm lon hsdSB (rB- mB-) araB::T7RNAP-tetA∙an E. coli B strain carrying the T7 RNA polymerase gene in the araB locus of the araBAD operon q.∙Transformed plasmids containing T7 promoter driven expression are repressed until L-arabinose induction of T7 RNA polymerase.∙Derived from BL21.∙See the product page for more information.∙Brian Caliendo (Voigt lab) reported trouble getting the Datsenko and Wanner (2000) plasmid pCP20 to transform into this strain, when other strains transformed fine. Cause is unknown.5.BL21(DE3)F–ompT gal dcm lon hsdSB (rB-mB-) λ(DE3 [lacI lacUV5-T7 gene 1 ind1 sam7nin5])∙an E. coli B strain with DE3, a λ prophage carrying the T7 RNA polymerase gene and lacI q∙Transformed plasmids containing T7 promoter driven expression are repressed until IPTG induction of T7 RNA polymerase from a lacpromoter.∙Derived from B834 (Wood, 1966) by transducing to Met+.∙See the original Studier paper or the summary in Methods in Enzymology for more details.∙Whole genome sequence available [1]6.BL21 (DE3) pLysSF- ompT gal dcm lon hsdSB (rB- mB-) λ(DE3) pLysS(cm R)∙pLysS plasmid chloramphenicol resistant; grow with chloramphenicol to retain plasmid∙Chloramphenicol resistant∙The pLysS plasmid encodes T7 phage lysozyme, an inhibitor for T7 polymerase which reduces and almost eliminates expression fromtransformed T7 promoter containing plasmids when not induced.∙see Moffatt87 for details of pLysS and pLysE plasmids7.BNN93F- tonA21 thi-1 thr-1 leuB6 lacY1 glnV44 rfbC1 fhuA1 mcrB e14-(mcrA-)hsdR(rK -mK+) λ-∙Some C600 strains are really BNN93 8.BNN97∙BNN93 (λgt11)o A λgt11 lysogen producing phage at 42C9.BW26434, CGSC Strain # 7658Δ(araD-araB)567, Δ(lacA-lacZ)514(::kan), lacIp-4000(lacI q), λ-, rpoS396(Am)?, rph-1, Δ(rhaD-rhaB)568, hsdR514∙This information is from a printout sent by the E. coli Genetic Stock Center with the strain.∙ B.L. Wanner strain∙rph-1 is a 1bp deletion that results in a frameshift over last 15 codons and has a polar effect on pyrE leading to suboptimalpyrimidine levels on minimal medium. (Jensen 1993 J Bact. 175:3401) ∙Δ(araD-araB)567 was formerly called ΔaraBAD AH33 by Datsenko and Wanner∙Am = amber(UAG) mutation∙Reference: Datsenko and Wanner, 2000, PNAS, 97:6640NOTE:∙This promoter driving the expression of lacI was sequenced in this strain using a primer in mhpR (upstream of lacI) and a primer in the opposite orientation in lacI. The lac promoter was found to be identical to wildtype. Thus, the -35 sequence was GCGCAA not GTGCAA as expected with lacI q. Therefore this strain (or at least theversion obtained from the E. coli Genetic Stock Center) does NOT appear to be lacI q. According to Barry Wanner, this is an unexpected result. -Reshma 13:19, 5 May 2005 (EDT)∙"We have now confirmed that BW25113, BW25141, and BW26434 are all lacI+, and not lacI q. We thank you for alerting us to the error with respect to BW26434. Apparently, the lacI region was restored to wild-type in a predecessor of BW25113." (from Barry Wanner November 18, 2005)∙The genotype has been corrected at the CGSC10.C600F- tonA21 thi-1 thr-1 leuB6 lacY1 glnV44 rfbC1 fhuA1 λ-∙There are strains circulating with both e14+(mcrA+) and e14-(mcrA-) ∙General purpose host∙See CGSC#3004∙References: Appleyard, R.K. (1954) Genetics 39, 440; Hanahan, D.(1983) J. Mol. Biol. 166, 577.11.C600 hflA150 (Y1073, BNN102)F- thi-1 thr-1 leuB6 lacY1 tonA21 glnV44 λ- hflA150(chr::Tn10) ∙host for repressing plaques of λgt10 when establishing cDNA libraries∙Reference Young R.A. and Davis, R. (1983) Proc. Natl. Acad. Sci.USA 80, 1194.∙Tetracycline resistance from the Tn10 insertion12.CSH50F- λ- ara Δ(lac-pro) rpsL thi fimE::IS1∙See CGSC#8085∙References: Miller, J.H. 1972. Expts.in Molec.Genetics, CSH 0:14-0;Blomfeld et al., J.Bact. 173: 5298-5307, 1991.13.D1210HB101 lacI q lacY+14.DB3.1F- gyrA462 endA1 glnV44 Δ(sr1-recA) mcrB mrr hsdS20(rB -, mB-) ara14 galK2lacY1 proA2 rpsL20(Sm r) xyl5 Δleu mtl1∙useful for propagating plasmids containing the ccdB operon.∙gyrA462 enables ccdB containing plasmid propagation∙streptomycin resistant∙appears to NOT contain lacI (based on a colony PCR) --Austin Che 16:16, 18 June 2007 (EDT)<biblio>1.Bernard-JMolBiol-1992 pmid=13243242.Miki-JMolBiol-1992 pmid=1316444</biblio>15.DH1endA1 recA1 gyrA96 thi-1 glnV44 relA1 hsdR17(rK - mK+) λ-∙parent of DH5α∙An Hoffman-Berling 1100 strain derivative (Meselson68)∙more efficient at transforming large (40-60Kb) plasmids∙nalidixic acid resistant∙Reference: Meselson M. and Yuan R. (1968) Nature 217:1110 PMID 4868368.16.DH5αF- endA1 glnV44 thi-1 recA1 relA1 gyrA96 deoR nupG Φ80d lacZΔM15Δ(lacZYA-argF)U169, hsdR17(r K- m K+), λ–∙An Hoffman-Berling 1100 strain derivative (Meselson68)∙Promega also lists phoA∙nalidixic acid resistant∙References:o FOCUS (1986) 8:2, 9.o Hanahan, D. (1985) in DNA Cloning: A Practical Approach (Glover, D.M., ed.), Vol. 1, p. 109, IRL Press, McLean,Virginia.o Grant, S.G.N. et al. (1990) Proc. Natl. Acad. Sci. USA 87: 4645-4649 PMID 2162051.o Meselson M. and Yuan R. (1968) Nature 217:1110 PMID 4868368.17.DH10B (Invitrogen)F- endA1 recA1 galE15 galK16 nupG rpsL ΔlacX74 Φ80lacZΔM15 araD139 Δ(ara,leu)7697 mcrA Δ(mrr-hsdRMS-mcrBC) λ-∙suitable for cloning methylated cytosine or adenine containing DNA ∙an MC1061 derivative (Casadaban80). Prepare cells for chemical transformation with CCMB80 buffer∙blue/white selection∙While DH10B has been classically reported to be galU galK, the preliminary genome sequence for DH10B indicates that DH10B (and by their lineage also TOP10 and any other MC1061 derivatives) isactually galE galK galU+. Dcekiert 16:37, 23 January 2008 (CST)∙Genome sequence indicates that DH10B is actually deoR+. Presumably TOP10 and MC1061 are also deoR+.∙Streptomycin resistant∙References:o Casdaban, M. and Cohen, S. (1980) J Mol Biol 138:179 PMID 6997493.o Grant, S.G.N. et al. (1990) Proc. Natl. Acad. Sci. USA 87: 4645-4649 PMID 2162051.o E. coli Genetic Stock Center, MC1061 Recordo DH10B Genome Sequencing Project, Baylor College of Medicineo Complete sequence is available, see Durfee08, PMID 18245285.12.DH12S (Invitrogen)mcrA Δ(mrr-hsdRMS-mcrBC) φ80d lacZΔM15 ΔlacX74 recA1 deoR Δ(ara, leu)7697 araD139 galU galK rpsL F' [proAB+ lacI q ZΔM15]∙host for phagemid and M13 vectors∙useful for generating genomic libraries containing methylated cytosine or adenine residues∙streptomycin resistant∙References: Lin, J.J., Smith, M., Jessee, J., and Bloom, F. (1991) FOCUS 13, 96.; Lin, J.J., Smith, M., Jessee, J., and Bloom, F. (1992) BioTechniques 12, 718.19.DM1 (Invitrogen)F- dam-13::Tn9(Cm R) dcm- mcrB hsdR-M+ gal1 gal2 ara- lac- thr- leu- tonR tsxR Su0∙Host for pBR322 and other non-pUC19 plasmids; useful for generating plasmids that can be cleaved with dam and dcm sensitive enzymes ∙Chloramphenicol resistant∙Promega lists as F' not F-∙Reference: Lorow-Murray D and Bloom F (1991) Focus 13:2020.E. cloni(r) 5alpha (Lucigen)fhuA2Δ(argF-lacZ)U169 phoA glnV44 Φ80 Δ(lacZ)M15 gyrA96 recA1 relA1 endA1 thi-1 hsdR17∙Common cloning strain.21.E. cloni(r) 10G (Lucigen)F- mcrAΔ(mrr-hsd RMS-mcr BC) end A1 rec A1 Φ80dlac ZΔM15 Δlac X74 ara D139 Δ(ara,leu)7697 gal U gal K rps L nup G λ- ton A∙Common cloning strain.∙Resistant to phage T1.22.E. cloni(r) 10GF' (Lucigen)[F´ pro A+B+ lac IqZΔM15::Tn10 (TetR)] /mcr A Δ(mrr-hsd RMS-mcr BC) end A1 rec A1 Φ80d lac ZΔM15 Δlac X74 ara D139 Δ(ara, leu)7697 gal U gal K rps L nup Gλ ton A∙Strain for cloning and single-strand DNA production.23.E. coli K12 ER2738 (NEB)F´proA+B+ lacIq Δ(lacZ)M15 zzf::Tn10(TetR)/ fhuA2 glnV Δ(lac-proAB) thi-1 Δ(hsdS-mcrB)5∙Phage propagation strain∙Also available from Lucigen Corporation.24.ER2566 (NEB)F- λ- fhuA2 [lon] ompT lacZ::T7 gene 1 gal sulA11 Δ(mcrC-mrr)114::IS10 R(mcr-73::miniTn10-TetS)2 R(zgb-210::Tn10)(TetS) endA1 [dcm]∙Host strain for the expression of a target gene cloned in the pTYB vectors.∙Carry a chromosomal copy of the T7 RNA polymerase gene inserted into lacZ gene and thus under the control of the lac promoter. In the absence of IPTG induction expression of T7 RNA polymerase issuppressed by the binding of lac I repressor to the lac promoter.∙Deficient in both lon and ompT proteases.25.ER2267 (NEB)F´ proA+B+ lacIq Δ(lacZ)M15 zzf::mini-Tn10 (KanR)/ Δ(argF-lacZ)U169 glnV44 e14-(McrA-) rfbD1? recA1 relA1? endA1 spoT1? thi-1Δ(mcrC-mrr)114::IS10∙Commonly used for titering M13 phage because of the strain's F' plasmid, which carries KanR, and its slow growth, which promotes easy visualization of plaques.26.HB101F- mcrB mrr hsdS20(rB - mB-) recA13 leuB6 ara-14 proA2 lacY1 galK2 xyl-5mtl-1 rpsL20(Sm R) glnV44 λ-Please note that different sources have different genotypes so treat this information with caution.∙From a GIBCO BRL list of competent cells.∙Hybrid of E. coli K12 and E. coli B (but 98% K strain AB266 according to Smith et al.)∙Host for pBR322 and many plasmids∙Sigma lists the deletion Δ(gpt,proA). Check this.∙Promega does not list F-, mcrB, or mrr∙Streptomycin resistant∙References:o Boyer, H.W. and Roulland-Dussoix, D. (1969) J. Mol. Biol. 41, 459.o Smith, M., Lorow, D., and Jessee, J. (1989) FOCUS 11, 56 - pdf version from Invitrogeno Lacks S and Greenberg JR (1977) J Mol Biol 114:153.27.HMS174(DE3)F- recA1 hsdR(rK12- mK12+) (DE3) (Rif R)∙HMS174 strains provide the recA mutation in a K-12 background. Like BLR, these strains may stabilize certain target genes whoseproducts may cause the loss of the DE3 prophage.∙DE3 indicates that the host is a lysogen of lDE3, and therefore carries a chromosomal copy of the T7 RNA polymerase gene undercontrol of the lacUV5 promoter. Such strains are suitable forproduction of protein from target genes cloned in pET vectors by induction with IPTG.28.High-Control(tm) BL21(DE3) (Lucigen)F– ompT gal dcm hsdSB (rB- mB-) (DE3)/Mini-F lacI q1(Gent r)∙The HI-Control BL21(DE3) cells contain a single-copy BAC plasmid harboring a specially engineered version of the lacI q1 repressor allele. The lacI q1 allele expresses ~170-fold more lac repressor protein than the wild-type lacI gene.∙The increased pool of lac repressor in HI-Control BL21(DE3) cells maintains tight control over the expression of T7 RNA polymerase from the lacUV5 promoter, reducing leaky expression of genes cloned under a T7 promoter.∙an E. coli B strain with DE3, a λ prophage carrying the T7 RNA polymerase gene and lacI q∙Transformed plasmids containing T7 promoter driven expression are repressed until IPTG induction of T7 RNA polymerase from a lacpromoter.29.High-Control(tm) 10G (Lucigen)F- mcrAΔ(mrr-hsd RMS-mcr BC) end A1 rec A1 Φ80dlac ZΔM15 Δlac X74 ara D139 Δ(ara,leu)7697 gal U gal K rps L nup G λ- ton A/Mini-F lacI q1(Gent r) ∙The HI-Control 10G cells contain a single-copy BAC plasmid harboring a specially engineered version of the lacI q1 repressor allele. The lacI q1 allele expresses ~170-fold more lac repressor protein than the wild-type lacI gene.∙For stable cloning of T7 protein expression plasmids.∙Resistant to phage T1.30.IJ1126E. coli K-12 recB21 recC22 sbcA5 endA gal thi Su+ Δ(mcrC-mrr)102::Tn10 See Endy:IJ112631.IJ1127IJ1126 lacUV5 lacZ::T7 gene1-KnrSee Endy:IJ112732.JM83rpsL ara Δ(lac-proAB) Φ80dlacZΔM15∙Sigma lists thi. Check this.∙streptomycin resistant33.JM101glnV44 thi-1 Δ(lac-proAB) F'[lacI q ZΔM15 traD36 proAB+] ∙host for M13mp vectors∙recA+, r K+∙original blue/white cloning strain∙has all wt restriction systems∙References: Messing, J. et al. (1981) Nucleic Acids Res. 9, 309;Yanisch-Perron, C., Vieira, J., and Messing, J. (1985) Gene 33, 103.34.JM103endA1 glnV44 sbcBC rpsL thi-1 Δ(lac-proAB) F'[traD36 proAB+ lacI qlacZΔM15]∙streptomycin resistant∙References: Hanahan, D. (1983) J. Mol. Biol. 166:557-80.∙NEB says this strain encodes a prophage encoded EcoP1 endonuclease.∙Sigma lists (P1) (r K-m K+ rP1+ mP1+)35.JM105endA1 glnV44 sbcB15 rpsL thi-1 Δ(lac-proAB) [F' traD36 proAB+ lacI qlacZΔM15] hsdR4(rK -mK+)∙Sigma lists sbcC∙streptomycin resistant∙References: Yanisch-Perron, C., Vieira, J., and Messing, J. (1985) Gene 33, 103.36.JM106endA1 glnV44 thi-1 relA1 gyrA96 Δ(lac-proAB) F- hsdR17(rK -mK+)∙References: Yanisch-Perron, C., Vieira, J., and Messing, J. (1985) Gene 33, 103.37.JM107endA1 glnV44 thi-1 relA1 gyrA96 Δ(lac-proAB) [F' traD36 proAB+ lacI qlacZΔM15] hsdR17(RK - mK+) λ-∙host for M13mp vectors∙recA+, r K+∙Sigma lists e14- (McrA-)∙nalidixic acid resistant∙References: Yanisch-Perron, C., Vieira, J., and Messing, J. (1985) Gene 33, 103.38.JM108endA1 recA1 gyrA96 thi-1 relA1 glnV44 Δ(lac-proAB) hsdR17 (rK - mK+)∙nalidixic acid resistant∙deficient in expression of the lon protease due to IS186 transposon insertion -- J Mairhofer 18:59, 24 March 2010 (CET)<biblio>1.Reference pmid=20138928</biblio>39.JM109endA1 glnV44 thi-1 relA1 gyrA96 recA1 mcrB+Δ(lac-proAB) e14- [F' traD36proAB+ lacI q lacZΔM15] hsdR17(rK -mK+)∙From NEB∙Partly restriction-deficient; good strain for cloning repetitive DNA (RecA–).∙Suppresses many amber mutations when glutamine is acceptable butnot the S100 or S7mutations of λ, e.g., λgt11.∙Can also be used for M13 cloning/sequencing and blue/white screening.∙Sigma lists e14-∙nalidixic acid resistant∙deficient in expression of the lon protease due to IS186 transposon insertion -- J Mairhofer 18:59, 24 March 2010 (CET) ∙From C. Yanisch-Perron, J. Vieira, and J. Messing. Improved M13 phage cloning vectors and host strains: nucleotide sequences of the M13mp18 and pUC19 vectors. Gene, 33(1):103–19, 1985.∙Some information from Mary Berlyn at the E. coli Genetic Stock Center: One of the reasons the original curator of this collection did not accession the JM109, JM103, etc. strains was because she found it impossible to be sure of the derivation and therefore the details of the genotype. But I think it's safe to assume that the F' in this strain is derived from or similar to F128 which extends from the proBA region through the lac operon. It thus carries the wildtype genes for all loci in that region except those indicated as mutant for the genotype of the F'. So it carries the lacZ(alpha-complementation) deletion lacZ58(M150 and the lacI mutation lacIq, but it has the lacY+ gene also on the F-prime. On thechromosome it lacks all the lac operon genes.NOTE: The promoter driving the expression of lacI was sequenced in this strain using a primer in mhpR (upstream of lacI) and a primer in the opposite orientation in lacI. The lac promoter was found to be identical to wildtype. Thus, the -35 sequence was GCGCAA not GTGCAA as expected with lacI Q. Therefore this strain (or at least the version we have) does NOT appear to be lacI Q unless there is another copy of lacI elsewhere. This result is somewhat confirmed by the fact that a lacI regulated promoter driving expression of YFP on a medium copy vector does not repress completely. -Reshma 13:48, 5 May 2005 (EDT)40.JM109(DE3)JM109 + λ(DE3)∙DE3 prophage carrying T7 polymerase expression cassette∙Same cassette as BL21(DE3) carrying a lac inducible T7 RNA polymerase and lacI q∙nalidixic acid resistant41.JM110rpsL thr leu thi lacY galK galT ara tonA tsx dam dcm glnV44 Δ(lac-proAB)e14- [F' traD36 proAB+ lacI q lacZΔM15] hsdR17(rK -mK+)∙Sigma fails to list tonA tsx e14 fhuA hsdR17∙(e14-) status uncertain∙streptomycin resistant42.JM2.300lacI22, LAM-, e14-, rpsL135(strR), malT1(LamR), xyl-7, mtl-1, thi-1 ∙Some folks have been using this strain (i.e., Elowitz, Gardner) and it took me too long to find the CGSC#.∙This strain is no longer available from the CGSC43.LE392glnV44 supF58 (lacY1 or ΔlacZY) galK2 galT22 metB1 trpR55 hsdR514(rK -mK+)∙Sigma lists F- e14- 44.Mach1ΔrecA1398 endA1 tonA Φ80ΔlacM15 ΔlacX74 hsdR(rK - mK+)∙From Invitrogen∙Doubling time approx. 50 min and supposedly fastest growing chemically competent cloning strain available∙Mach1 cells are derivatives of E. coli W strains (ATCC 9637, S. A.Waksman), rather than E. coli K-12. This may have implications for BL-1 status for some facilities (apparently not for MIT).∙See Bloom04 patent for details on the construction and properties of this strain.45.MC1061F-Δ(ara-leu)7697 [araD139]B/rΔ(codB-lacI)3 galK16 galE15 λ-e14-mcrA0 relA1 rpsL150(strR) spoT1 mcrB1 hsdR2(r-m+)∙Streptomycin resistant∙The thr-leu region was transduced from an E. coli B/r strain (SB3118) in early steps of strain construction.∙Parent of DH10B/TOP10 and derived strains∙References:o E. coli Genetic Stock Center, MC1061 Recordo Casdaban, M. and Cohen, S. (1980) J Mol Biol 138:179 PMID 6997493.o Complete DH10B sequence is available, see Durfee08, PMID 18245285.46.MC4100Δ(argF-lac)169* &lambda- e14- flhD5301 Δ(fruK-yeiR)725 F- [araD139]B/r(fruA25)‡ relA1 rpsL150(strR) rbsR22 Δ(fimB-fimE)632(::IS1) deoC1∙The thr-leu region was transduced from an E. coli B/r strain (SB3118) in early steps of strain construction.∙This paper compares MC4100 to MG1655 and describes the significant deletions.∙*The paper referenced above showed that this deletion was larger than previously known. The deletion now covers ykfD-b0350.∙‡The fruA25 allele is attributed to the deletion of fruK-yeiR. This means fruA is present but its promoter has been deleted.∙The paper also shows that the e14 element is deleted in MC4100. One of the genes removed by this deletion is mcrA, which encodes anenzyme that restricts DNA containing methylcytosine. However,other E. coli K-12 restriction/modification systems are stillpresent in MC4100. MC4100 still encodes the McrBC5-methylcytosine=specific restriction enzyme and theHsdR/HsdS/HsdM type I restriction-modification complex.∙Table three of the paper lists all genes believed to be deleted in MC4100. The methods used in the paper can detect deletions but not loss of function mutations.∙See CGSC#615247.MG1655F- λ- ilvG- rfb-50 rph-1This is the "wild type" K-12 strain which was sequenced, and should be used when PCRing genes from the sequenced genome. It also looks very healthy under the microscope -- a dramatic difference from most of the cloning strains, which appear sick.∙See CGSC#6300∙See ATCC 700926<biblio>1.Blattner-Science-1997 pmid=9278503</biblio>∙More accurate sequence correcting 243 errors in the original sequencing Horiuchi2006. New Genbank accession number U00096.2 48.OmniMAX2From Invitrogen: "This strain overexpresses the Lac repressor (lacIq gene). For blue/white screening, you will need to add IPTG to induce expression from the lac promoter. Strain is resistant to T1 bacteriophage."F′ {proAB+ lacIq lacZΔM15 Tn10(TetR) Δ(ccdAB)} mcrAΔ(mrr-hsdRMS-mcrBC) φ80(lacZ)ΔM15 Δ(lacZYA-argF) U169 endA1 recA1 supE44 thi-1 gyrA96 relA1 tonA panD49.OverExpress(tm)C41(DE3) (Lucigen)F– ompT gal dcm hsdSB (rB- mB-)(DE3)∙The OverExpress strains contain genetic mutations phenotypically selected for conferring tolerance to toxic proteins. The strain C41(DE3) was derived from BL21(DE3). This strain has at least one uncharacterized mutation, which prevents cell death associated with expression of many recombinant toxic proteins. The strain C43(DE3) was derived from C41(DE3) by selecting for resistance toa different toxic protein and can express a different set of toxicproteins to C41(DE3).∙an E. coli B strain with DE3, a λ prophage carrying the T7 RNA polymerase gene and lacI q∙Transformed plasmids containing T7 promoter driven expression are repressed until IPTG induction of T7 RNA polymerase from a lacpromoter.50.OverExpress(tm)C41(DE3)pLysS (Lucigen)F– ompT gal dcm hsdSB (rB- mB-)(DE3)pLysS (Cm r)∙The OverExpress strains contain genetic mutations phenotypically selected for conferring tolerance to toxic proteins. The strain C41(DE3) was derived from BL21(DE3). This strain has at least one uncharacterized mutation, which prevents cell death associatedwith expression of many recombinant toxic proteins. The strainC43(DE3) was derived from C41(DE3) by selecting for resistance toa different toxic protein and can express a different set of toxicproteins to C41(DE3).∙an E. coli B strain with DE3, a λ prophage carrying the T7 RNA polymerase gene and lacI q∙Transformed plasmids containing T7 promoter driven expression are repressed until IPTG induction of T7 RNA polymerase from a lacpromoter.∙The pLysS plasmid encodes T7 phage lysozyme, an inhibitor for T7 polymerase which reduces and almost eliminates expression fromtransformed T7 promoter containing plasmids when not induced. 51.OverExpress(tm)C43(DE3) (Lucigen)F– ompT gal dcm hsdSB (rB- mB-)(DE3)∙The OverExpress strains contain genetic mutations phenotypically selected for conferring tolerance to toxic proteins. The strain C41(DE3) was derived from BL21(DE3). This strain has at least one uncharacterized mutation, which prevents cell death associated with expression of many recombinant toxic proteins. The strain C43(DE3) was derived from C41(DE3) by selecting for resistance toa different toxic protein and can express a different set of toxicproteins to C41(DE3).∙an E. coli B strain with DE3, a λ prophage carrying the T7 RNA polymerase gene and lacI q∙Transformed plasmids containing T7 promoter driven expression are repressed until IPTG induction of T7 RNA polymerase from a lacpromoter.52.OverExpress(tm)C43(DE3)pLysS (Lucigen)F– ompT gal dcm hsdSB (rB- mB-)(DE3)pLysS (Cm r)∙The OverExpress strains contain genetic mutations phenotypically selected for conferring tolerance to toxic proteins. The strain C41(DE3) was derived from BL21(DE3). This strain has at least one uncharacterized mutation, which prevents cell death associatedwith expression of many recombinant toxic proteins. The strainC43(DE3) was derived from C41(DE3) by selecting for resistance toa different toxic protein and can express a different set of toxicproteins to C41(DE3).∙an E. coli B strain with DE3, a λ prophage carrying the T7 RNA polymerase gene and lacI q∙Transformed plasmids containing T7 promoter driven expression are repressed until IPTG induction of T7 RNA polymerase from a lacpromoter.∙The pLysS plasmid encodes T7 phage lysozyme, an inhibitor for T7 polymerase which reduces and almost eliminates expression fromtransformed T7 promoter containing plasmids when not induced. 53.Rosetta(DE3)pLysSF-ompT hsdSB (RB-mB-) gal dcm λ(DE3 [lacI lacUV5-T7 gene 1 ind1 sam7 nin5])pLysSRARE (Cam R)∙an E. coli B strain with DE3, a λ prophage carrying the T7 RNA polymerase gene and lacI q∙Transformed plasmids containing T7 promoter driven expression are repressed until IPTG induction of T7 RNA polymerase from a lacpromoter.∙Chloramphenicol resistant∙pLysSRARE contains tRNA genes argU, argW, ileX, glyT, leuW, proL, metT, thrT, tyrU, and thrU. The rare codons AGG, AGA, AUA, CUA, CCC, and GGA are supplemented.∙The pLysS plasmid encodes T7 phage lysozyme, an inhibitor for T7 polymerase which reduces and almost eliminates expression fromtransformed T7 promoter containing plasmids when not induced.∙see Moffatt87 for details of pLysS and pLysE plasmids∙Novagen strain manual54.Rosetta-gami(DE3)pLysSΔ(ara-leu)7697 ΔlacX74 ΔphoA PvuII phoR araD139 ahpC galE galK rpsL (DE3) F'[lac+ lacI q pro] gor522::Tn10 trxB pLysSRARE (Cam R, Str R, Tet R)∙an E. coli K-12 strain with DE3, a λ prophage carrying the T7 RNA polymerase gene and lacI q∙Transformed plasmids containing T7 promoter driven expression are repressed until IPTG induction of T7 RNA polymerase from a lacpromoter.∙ahpC mutation allows trxB/gor double mutants to grow in the absence of reducing medium∙pLysSRARE contains tRNA genes argU, argW, ileX, glyT, leuW, proL, metT, thrT, tyrU, and thrU. The rare codons AGG, AGA, AUA, CUA, CCC, and GGA are supplemented.∙The pLysS plasmid encodes T7 phage lysozyme, an inhibitor for T7 polymerase which reduces and almost eliminates expression fromtransformed T7 promoter containing plasmids when not induced.∙see Moffatt87 for details of pLysS and pLysE plasmids∙Chloramphenicol resistant∙Kanamycin resistant∙Tetracycline resistant∙Streptomycin resistant∙Novagen strain manual55.RR1HB101 recA+56.RV308lacIq-, su-, ΔlacX74, gal IS II::OP308, strA K12 derivative used for industrial protein production. ATCC strain 31608, deposited by Genentech.57.SOLR (Stratagene)e14-(McrA-) Δ(mcrCB-hsdSMR-mrr)171 sbcC recB recJ uvrC umuC::Tn5 (Kan r) lac gyrA96 relA1 thi-1 endA1 λR [F’ proAB lacI q Z ΔM15]C Su-∙Used in phagemid recovery (LambdaZap)∙Kanamycin resistant∙Stratagene E. coli Genotype Strains58.SS320 (Lucigen)F'[proAB+lacIqlacZΔM15 Tn10 (tet r)]hsdR mcrB araD139Δ(araABC-leu)7679 Δlac X74 galUgalK rpsL thi∙Useful for phage display.∙Sidhu, S.S., Weiss, G.A., and Wells, J.A. (2000) J. Mol. Biol. 296, 487-495.59.STBL2 (Invitrogen)F- endA1 glnV44 thi-1 recA1 gyrA96 relA1 Δ(lac-proAB) mcrAΔ(mcrBC-hsdRMS-mrr) λ-∙host for unstable sequences such as retroviral sequences and direct repeats∙nalidixic acid resistant∙References: Trinh, T., Jessee, J., Bloom, F.R., and Hirsch, V. (1994) FOCUS 16, 78.60.STBL3 (Invitrogen)F- glnV44 recA13 mcrB mrr hsdS20(rB-, mB-) ara-14 galK2 lacY1 proA2 rpsL20 xyl-5 leu mtl-1∙Streptomycin resistant∙endA+, use care in preparing DNA from this strain61.STBL4endA1 glnV44 thi-1 recA1 gyrA96 relA1 Δ(lac-proAB) mcrAΔ(mcrBC-hsdRMS-mrr) λ- gal F'[ proAB+ lacI q lacZΔM15 Tn10]∙Tetracycline resistant (from Tn10 insertion)∙STBL2 + blue/white selection62.SURE (Stratagene)。

大肠杆菌的专业书籍
大肠杆菌是常见的肠道细菌，也是许多重要实验室菌株的代表。

以下是几本介绍大肠杆菌的专业书籍：
1.《大肠杆菌遗传学》（Genetics of Escherichia coli）。

作者：Snyder L、Peters JE、Henkin TM。

该书详细介绍了大肠杆菌基
因组和表达调控，包括基因转录、RNA加工和翻译等方面。

2.《大肠杆菌生长、代谢和调控》（Escherichia coli Growth, Metabolism and Regulation）。

作者：Lin ECC、Lynch AS。

该书深
入探讨了大肠杆菌的生长和代谢，包括碳、氮、硫等营养元素的代谢
途径以及调控机制。

3.《大肠杆菌分子生物学实验技术》（Molecular Biology Techniques of Escherichia coli）。

作者：王明奎。

该书介绍了大
肠杆菌分子生物学实验的基本原理和方法，包括基因克隆、表达、突
变及鉴定等方面。

4.《大肠杆菌荧光蛋白和其他标记基因的应用》（Applications of Fluorescent Protein and Other Luminescent Markers in Escherichia coli）。

作者：Hernaiz MJ。

该书介绍了大肠杆菌荧光
蛋白和其他标记基因的应用，包括细胞定位、蛋白间相互作用等方面。

以上是几本较为知名的关于大肠杆菌的专业书籍，读者可以根据
自己的兴趣和研究领域进行选择。

From OpenWetWare1 Nomenclature & Abbreviations2 Methylation Issues in E. coli3 Commonly used strains3.1 AG13.2 AB11573.3 BL21(AI)3.4 BL21(DE3)3.5 BL21 (DE3) pLysS3.6 BNN933.7 BW26434, CGSC Strain # 76583.8 C6003.9 C600 hflA150 (Y1073, BNN102)3.10 CSH503.11 D12103.12 DB3.13.13 DH13.14 DH5α3.15 DH10B (Invitrogen)3.16 DH12S (Invitrogen)3.17 DM1 (Invitrogen)3.18 ER2566 (NEB)3.19 ER2267 (NEB)3.20 HB1013.21 HMS174(DE3)3.22 IJ11263.23 IJ11273.24 JM833.25 JM1013.26 JM1033.27 JM1053.28 JM1063.29 JM1073.30 JM1083.31 JM1093.32 JM109(DE3)3.33 JM1103.34 JM2.3003.35 LE3923.36 Mach13.37 MC10613.38 MC41003.39 MG16553.40 OmniMAX23.41 Rosetta(DE3)pLysS 3.42 Rosetta-gami(DE3)pLysS 3.43 RR13.44 STBL2 (Invitrogen)3.45 STBL43.46 SURE (Stratagene)3.47 SURE2 (Stratagene)3.48 TOP10 (Invitrogen)3.49 Top10F' (Invitrogen)3.50 W31103.51 XL1-Blue (Stratagene)3.52 XL2-Blue (Stratagene)3.53 XL2-Blue MRF' (Stratagene)3.54 XL1-Red (Stratagene)3.55 XL10-Gold (Stratagene)3.56 XL10-Gold KanR (Stratagene)4 Other genotype information sources 5 ReferencesA listed gene name means that gene carries a loss of function mutation, a Δ preceding a gene name means the gene is deleted. If a gene is not listed, it is not known to be mutated. Prophages present in wt K-12 strains (F, λ, e14, rac) are listed only if absent. E. coliB strains are naturally lon- and dcm-.F - = Does not carry the F plasmidF + = Carries the F plasmid. The cell is able to mate with F - through conjugation.F'[ ] = Carries an F plasmid that has host chromosomal genes on it from a previous recombination event. This cell can also mate with F - through conjugation. Chromosomal genes carried in the F plasmid are listed in brackets.r B/K +/- = The (B/K) defines the strain lineage. The +/- indicates whether the strain has or hasn't got the restriction system.m B/K +/- = The (B/K) defines the strain lineage. The +/- indicates whether the strain has or hasn't got the modification (methylation) system.hsdS = Both restriction and methylation of certain sequences is deleted from the strain. If you transform DNA from such a strain into a wild type strain, it will be degraded.hsdR = For efficient transformation of cloned unmethylated DNA from PCR amplificationsINV( ) = chromosomal inversion between locations indicatedahpC = mutation to alkyl hydroperoxide reductase conferring disulfide reductase activityara-14 = cannot metabolize arabinosearaD = mutation in L-ribulose-phosphate 4-epimerase blocks arabinose metabolismcycA = mutation in alanine transporter; cannot use alanine as a carbon sourcedapD = mutation in succinyl diaminopimelate aminotransferase leads to succinate or (lysine +methionine) requirementΔ( ) = chromosomal deletion of genes between the listed genes (may include unlisted genes!)dam = adenine methylation at GATC sequences abolished; high recombination efficiency; DNA repair turned ondcm = cytosine methylation at second C of CCWGG sites abolished通常dam/dcm都是默认的，无需标注，只有dam -、dcm -才有必要标出来，那是被迫使用某些酶切位点时才用来扩增质粒的特殊菌株。

版本号：M16B01V1.0 Exonuclease I(E.coli)目录号:RK20531规格:1,500U/3,000U/15,000U浓度:20,000U/mL产品组成Exonuclease I(E.coli)(20,000U/mL)RM20519 10X Exonuclease I Reaction Buffer RM20130产品说明Exonuclease I(E.coli)沿3’-5’方向降解单链DNA上的单核苷酸，不会降解由磷酰基团或乙酰基团封闭了3’-OH末端的DNA单链。

Exonuclease I能从含有双链延伸产物的反应混合物中降解多余的单链寡核苷酸引物；能分析是否存在含3’-OH 末端的单链DNA。

产品来源E.coli NM554来源的Exonuclease I基因在大肠杆菌中表达并分离纯化得到。

活性定义1活性单位(U)是指在50μL反应体系中，将37°C30min内催化0.17mg/mL[3H]-ssDNA释放10nmol酸不溶性物质所需的酶量。

反应条件1X Exonuclease I Reaction Buffer，37°C反应1X Exonuclease I Reaction Buffer组成67mM Glycine-KOH,6.7mM MgCl2,10mMβ-ME,pH9.5 @25°C保存温度-20°C酶存储液10mM Tris-HCl,100mM NaCl,5mMβ-ME,0.5mM EDTA, 100μg/mL BSA,50%Glycerol,pH7.5@25°C热失活80°C加热20min 操作说明Exonuclease I清除PCR引物操作流程1.向5μL PCR扩增产物中加入0.5μL Exonuclease I和1μL 重组虾碱性磷酸酶(rSAP)。

2.混匀并瞬时离心，在37°C反应15min。

大肠杆菌分子遗传学及其在微生物代谢中的应用大肠杆菌，缩写为E.coli，是一种广泛存在于自然界中的细菌，它生长繁殖速度快，并且易于培养和操作。

因此，E.coli 已经成为了微生物学和分子遗传学中最常用的研究对象之一。

一、大肠杆菌分子遗传学1. 大肠杆菌基因组大肠杆菌具有一个长度为460万个碱基对的双链DNA基因组，其中包含有4200多个基因，基因密度为每10KB含有1个基因。

这个基因组分为一个圆形的染色体和许多不同的质粒，其中一些质粒可以用于克隆表达和其他的实验室用途。

2. 大肠杆菌基因调控大肠杆菌中的基因表达是高度调控的。

许多转录因子，包括RNA聚合酶和其他的激活因子，可以通过多种不同的方式影响基因表达。

例如，一个重要的调控机制是Rho因子的终止作用，这会影响RNA的合成和核糖体的结合。

另外，许多转录因子也会结合到DNA的特定区域上，影响基因表达。

3. E.coli基因编辑技术近年来，人工合成DNA技术的迅速发展，使得科学家们可以人工合成全新的基因组，并且利用基因编辑技术实现对大肠杆菌基因组的定点操作。

基因编辑可以通过CRISPR-Cas9系统、ZFNs或者TALENs等方法来实现对特定的基因进行剪接、替换等操作，这为微生物学和生物技术领域的其他应用提供了巨大潜力。

二、大肠杆菌在微生物代谢中的应用1. 生产重要化合物大肠杆菌能够产生许多重要的化合物，包括植酸和乳酸等。

此外，大肠杆菌也可以被用于生产天然合成的内源物质，如虾青素和其他有机物质。

2. 乳糖代谢和呼吸酸代谢大肠杆菌可以通过乳糖代谢来维持它的生命活动。

这是通过产生乳糖酶来实现的，它使得E.coli能够将乳糖转化为葡萄糖。

此外，在氧化剂存在时，大肠杆菌也可以利用呼吸酸代谢来产生ATP能量，而在氧气不足时则利用发酵反应来产生能量。

3. 蛋白质表达大肠杆菌可以被用于大量生产重组蛋白质。

这是通过利用基因编辑和其他的操作来改变E.coli的基因组，使其可以表达人类或其他生物的特定蛋白质。

大肠杆菌的基因型-概述说明以及解释1.引言1.1 概述大肠杆菌是一种常见的革兰氏阴性杆菌，属于肠道菌群中的重要成员。

它在自然界和人体内广泛存在，并且具有广泛的基因型多样性。

这使得大肠杆菌成为了微生物遗传学和进化生物学领域的研究模型。

在大肠杆菌中，基因型是指该菌株拥有的基因组合和基因的分布情况。

大肠杆菌的基因型可以通过不同的方法进行分类和鉴定。

目前主要的分类方法包括单核苷酸多态性分析、基因片段分析和全基因组测序等。

通过这些方法，我们可以更全面地了解大肠杆菌的基因型组成和种群结构。

大肠杆菌的基因型在其功能和特点方面具有重要意义。

大肠杆菌是一种典型的益生菌，它在人体内具有多种有益作用，包括帮助消化吸收、维持肠道稳定性和参与免疫调节等。

不同基因型的大肠杆菌可能具有不同的功能特点，比如某些基因型可能携带耐药基因或致病因子，导致感染和疾病的发生。

因此，对大肠杆菌基因型的研究有助于我们深入了解其功能机制和生态适应能力。

总之，大肠杆菌作为一种常见的菌株，其基因型具有多样性和重要性。

通过研究大肠杆菌的基因型，我们可以深入探索其功能特点和生态适应能力，进一步促进微生物遗传学和进化生物学的研究。

未来，我们可以通过结合多样的研究方法和技术，进一步挖掘和解析大肠杆菌基因型的奥秘，并探索其在人体健康和疾病中的作用。

文章结构是指文章部分之间的逻辑关系和组织，它有助于读者理解文章的内容和思路。

本文的结构如下：1. 引言1.1 概述1.2 文章结构1.3 目的2. 正文2.1 大肠杆菌的基因型分类2.2 大肠杆菌基因型的功能和特点3. 结论3.1 大肠杆菌基因型的重要性3.2 未来研究的方向文章结构部分是为了描述本文的组织结构，它有助于读者了解文章的内容安排和逻辑关系。

在本文中，我们首先介绍引言部分，包括概述、文章结构和目的。

在概述中，我们简要介绍了大肠杆菌的基因型。

在文章结构中，我们明确了本文的结构和章节安排，帮助读者理解文章的整体框架。

E.coli Competent Cells BL21（DE3）产品套装编号：U0105A储存条件：-80℃保存 保存时间： 12月产品内容Competent Cells BL21（DE3）Control DNA （pUC19，10 pg/µl ）产品编号U01050A V01010A 包装规格100 μl ×10100 μl ×1■ 产品概述：BL21（DE3）感受态细胞是采用大肠杆菌BL21（DE3）菌株经特殊工艺处理得到的感受态细胞，可用于DNA 的化学转化。

■ Genotype ：F-omp T hsd SB （rB-mB －）gal dcm （DE3）.■ 细胞种类：BL21(DE3)是改造过的专门用来表达T7启动子启动基因的表达用大肠杆菌菌株。

该菌株中DE3编码T7RNA 聚合酶基因，可在 IPTG （安慰型诱导物）可作用于下，被正调控诱导表达，使得T7RNA 聚合酶大量表达（普通大肠杆菌无这种RNA 聚合酶，进而T7RNA 聚合酶作用于外源表达质粒载体上的T7启动子，促进下游外源的目的片段的转录，进而间接促进外源蛋白的表达。

因此该菌株是一个高效表达宿主，适合表达非毒性蛋白。

■ 转化效率：使用1 ng 的质粒DNA 进行转化时：100 µl Competent Cells BL21(DE3)/1 ng pUC19 进行转化时产生的菌落数＞1×107转化子/1 µg pUC19GeneCopoeia Inc. 19520 Amaranth Drive Germantown, Maryland 20874USA Tel: 301-515-6982; 1-866-360-9531Fax: 301-515-6983Web: GeneCopoeia TMExpressway to Discovery■ 使用步骤：1. 把感受态细胞置于冰中解冻。

E. coli genotypesContents[hide]1 Nomenclature & Abbreviations2 Methylation Issues in E. coli3 Commonly used strains3.1 AG13.2 AB11573.3 BL213.4 BL21(AI)3.5 BL21(DE3)3.6 BL21 (DE3) pLysS3.7 BNN933.8 BNN973.9 BW26434, CGSC Strain # 76583.10 C6003.11 C600 hflA150 (Y1073, BNN102)3.12 CSH503.13 D12103.14 DB3.13.15 DH13.16 DH5α3.17 DH10B (Invitrogen)3.18 DH12S (Invitrogen)3.19 DM1 (Invitrogen)3.20 E. cloni(r) 5alpha (Lucigen)3.21 E. cloni(r) 10G (Lucigen)3.22 E. cloni(r) 10GF' (Lucigen)3.23 E. coli K12 ER2738 (NEB)3.24 ER2566 (NEB)3.25 ER2267 (NEB)3.26 HB1013.27 HMS174(DE3)3.28 High-Control(tm) BL21(DE3) (Lucigen)3.29 High-Control(tm) 10G (Lucigen)3.30 IJ11263.31 IJ11273.32 JM833.33 JM1013.34 JM1033.35 JM1053.36 JM1063.37 JM1073.38 JM1083.39 JM1093.40 JM109(DE3)3.41 JM1103.42 JM2.3003.43 LE3923.44 Mach13.45 MC10613.46 MC41003.47 MG16553.48 OmniMAX23.49 OverExpress(tm)C41(DE3) (Lucigen)3.50 OverExpress(tm)C41(DE3)pLysS (Lucigen)3.51 OverExpress(tm)C43(DE3) (Lucigen)3.52 OverExpress(tm)C43(DE3)pLysS (Lucigen)3.53 Rosetta(DE3)pLysS3.54 Rosetta-gami(DE3)pLysS3.55 RR13.56 RV3083.57 SOLR (Stratagene)3.58 SS320 (Lucigen)3.59 STBL2 (Invitrogen)3.60 STBL3 (Invitrogen)3.61 STBL43.62 SURE (Stratagene)3.63 SURE2 (Stratagene)3.64 TG1 (Lucigen)3.65 TOP10 (Invitrogen)3.66 Top10F' (Invitrogen)3.67 W31103.68 XL1-Blue (Stratagene)3.69 XL1-Blue MRF' (Stratagene)3.70 XL2-Blue (Stratagene)3.71 XL2-Blue MRF' (Stratagene)3.72 XL1-Red (Stratagene)3.73 XL10-Gold (Stratagene)3.74 XL10-Gold KanR (Stratagene)4 Other genotype information sources5 ReferencesNomenclature & AbbreviationsA listed gene name means that gene carries a loss of function mutation, a Δ preceding a gene name means the gene is deleted. If a gene is not listed, it is not known to be mutated. Prophages present in wt K-12 strains (F, λ, e14, rac) are listed only if absent. E. coliB strains are naturally lon- and dcm-.F- = Does not carry the F plasmidF+ = Carries the F plasmid. The cell is able to mate with F- through conjugation.F'[ ] = Carries an F plasmid that has host chromosomal genes on it from a previous recombination event. This cell can also mate with F- through conjugation. Chromosomal genes carried in the F plasmid are listed in brackets.r B/K+/- = The (B/K) defines the strain lineage. The +/- indicates whether the strain has or hasn't got the restriction system.m B/K+/- = The (B/K) defines the strain lineage. The +/- indicates whether the strain has or hasn't got the modification (methylation) system.hsdS = Both restriction and methylation of certain sequences is deleted from the strain. If you transform DNA from such a strain into a wild type strain, it will be degraded.hsdR = For efficient transformation of cloned unmethylated DNA from PCR amplificationsINV( ) = chromosomal inversion between locations indicatedahpC = mutation to alkyl hydroperoxide reductase conferring disulfide reductase activityara-14 = cannot metabolize arabinosearaD = mutation in L-ribulose-phosphate 4-epimerase blocks arabinose metabolismcycA = mutation in alanine transporter; cannot use alanine as a carbon sourcedapD = mutation in succinyl diaminopimelate aminotransferase leads to succinate or (lysine + methionine) requirementΔ( ) = chromosomal deletion of genes between the listed genes (may include unlisted genes!)dam = adenine methylation at GATC sequences exist; high recombination efficiency; DNA repair turned ondcm = cytosine methylation at second C of CCWGG sites exist. dam & dcm are the default properties and always elided, while dam- or dcm- should be declare explicitlydeoR = regulatory gene that allows constitutive expression of deoxyribose synthesis genes; permits uptake of large plasmids. See Hanahan D, US Patent 4,851,348. ***This has been called intoquestion, as the DH10B genome sequence revealed that it is deoR+. See Durfee08, PMID 18245285.dnaJ = one of the chaparonins inactivated; stabilizes some mutant proteinsdut1 = dUTPase activity abolished, leading to increased dUTP concentrations, allowing uracil instead of thymine incorporation in DNA. Stable U incorporation requires ung gene mutation as well. endA1 = For cleaner preparations of DNA and better results in downstream applications due to the elimination of non-specific digestion by Endonuclease I(e14) = excisable prophage like element containing mcrA gene; present in K-12 but missing in many other strainsgalE = mutations are associated with high competence, increased resistance to phage P1 infection, and 2-deoxygalactose resistance. galE mutations block the production of UDP-galactose, resulting in truncation of LPS glycans to the minimal, "inner core". The exceptional competence ofDH10B/TOP10 is thought to be a result of a reduced interference from LPS in the binding and/or uptake of transforming DNA. galE15 is a point mutation resulting in a Ser123 -> Phe conversion near the enzyme's active site. See van Die, et al. PMID 6373734, Hanahan, et al. PMID 1943786, and EcoSal ISBN 1555811647. --Dcekiert 16:56, 23 January 2008 (CST)galk = mutants cannot metabolize galactose and are resistant to 2-deoxygalactose. galK16 is anIS2 insertion ~170bp downstream of the galK start codon. See EcoSal ISBN 1555811647. --Dcekiert 16:56, 23 January 2008 (CST)galU = mutants cannot metabolize galactosegor = mutation in glutathione reductase; enhances disulphide bond formationglnV = suppression of amber (UAG) stop codons by insertion of glutamine; required for some phage growthgyrA96 = mutation in DNA gyrase; conveys nalidixic acid resistancegyrA462 = mutation in DNA gyrase; conveys resistance to ccdB colicin gene producthflA150 = protease mutation stabilizing phage cII protein; high frequency of lysogenization by λΔ(lac)X74 = Deletion of the entire lac operon as well as some flanking DNA (complete deletion is Δcod-mhpF; see Mol.Micro., 6:1335, and J.Bact., 179:2573)lacI q or lacI Q = overproduction of the lac repressor protein; -35 site in promoter upstream of lacI is mutated from GCGCAA to GTGCAAlacI Q1 = overproduction of the lac repressor protein; contains a 15 bp deletion to create optimal -35site in promoter upstream of lacIlacY = deficient in lactose transport; deletion of lactose permease (M protein)lacZΔM15 = partial deletion of the lacZ gene that allows α complementation of the β-galactosidase gene; required for blue/white selection on XGal plates. Deletes the amino portion of lacZ (aa 11-41). leuB = requires leucineΔlon = deletion of the lon proteasemalA = cannot metabolize maltosemcrA = Mutation eliminating restriction of DNA methylated at the sequence C m CGG (possiblym CG). Carried on the e14 prophage (q.v.)mcrB = Mutation eliminating restriction of DNA methylated at the sequence R m CmetB = requires methioninemetC = requires methioninemrr = Mutation eliminating restriction of DNA methylated at the sequence C m AG or G m ACmtlA = cannot metabilize mannitol(Mu) = Mu prophage present. Muδ means the phage is defective.mutS - mutation inhibits DNA repair of mismatches in unmethylated newly synthesized strands nupG = same as deoRompT = mutation in outer membrane protein protease VII, reducing proteolysis of expressed proteins(P1) = Cell carries a P1 prophage. Cells express the P1 restriction system.(P2) = Cell carries a P2 prophage. Allows selection against Red+ Gam+ λ(φ80) = Cell carries the lambdoid prophage φ80. A defective version of this phage carryinglacZM15 deletion (as well as wild-type lacI, lacYA, and flanking sequences) is present in some strains. The φ80 attachment site is just adjacent to tonB.pLysS = contains pLysS plasmid carrying chloramphenicol resistance and phage T7 lysozyme, effective at attenuating activity of T7 RNA polymerase, for better inhibition of expression under non-induced conditions. The sequence can be found here.proA/B = requires prolinerecA1 = For reduced occurrence of unwanted recombination in cloned DNA; cells UV sensitive, deficient in DNA repairrecA13 = as for recA1, but inserts less stable.recBCD = Exonuclease V; mutation in RecB or RecC reduces general recombination by a factor of 100; impaired DNA repair; UV sensitive, easier propagation of inverted repeatsrecJ Exonuclease involved in alternate recombinationrelA = relaxed phenotype; permits RNA synthesis in absence of protein synthesisrha = blocked rhamose metabolismrnc = encodes RnaseIII (rnc-14 is a common null mutant)rne = encodes RnaseE (rne-3071 is a common temperature sensitive mutant)rpsL = mutation in ribosomal protein S12 conveying streptomycin resistance; also called strA sbcBC = ExoI activity abolished; usually present in recBC strains; recombination proficient, stable inverted repeatssr1 = cannot metabolize sorbitolsupE = glnVsupF = tyrTthi = requires thiaminethyA = requires thymidineTn10 = transposon normally carrying Tetracycline resistanceTn5 = transposon normally carrying Kanamycin resistancetonA = Mutation in outer membrane protein conveying resistance to phage T1 and phage T5 traD = Mutation eliminating transfer factor; prevents transfer of F plasmidtrxB = mutation in thioredoxin reductase; enhances disulphide bond formation in the cytoplasm tsx = outer membrane protein mutation conveying resistance to phage T6 and colicin KtyrT = suppression of amber (UAG) stop codons by insertion of tyrosine; needed for some phage infection such as λgt11.ung1 = allows uracil to exist in plasmid DNAxyl-5 = blocked xylose metabolismSm R = Streptomycin resistanceMethylation Issues in E. coliType I methylation systems:E. coli K-12 restricts DNA which is not protected by adenine methylation at sitesAA*C[N6]GTGC or GCA*C[N6]GTT, encoded by the hsdRMS genes(EcoKI). Deletions in these genes removes either the restriction or methylation or both of these functions.E. coli B derivative strains contain an hsdRMS system (EcoBI) restricting and protectiing thesequence TGA*[N8]TGCT or AGCA*[N8]TCA.The mcrA gene (carried on the e14 prophage) restricts DNA which is methylated in C m CWGG or m CG sequences (methylation by the dcm gene product).The mcrBC genes restrict R m C sequences.The mrr gene product restricts adenine methylated sequences at CAG or GAC sites.E. coli methylates the adenine in GATC (and the corresponding A on the opposite strand) with thedam gene product.M.EcoKII methylates the first A at the palindromic site ATGCAT (as well as the corresponding A on the opposite strand), see (Kossykh VG (2004) J. Bact 186: 2061-2067 PMID 15028690) Note that this article has been retracted; the retraction appears to center on textual plagarism, notexperimental results. The homology to AvaIII is real. I think I believe it. tk 20:28, 9 December 2005 (EST). Rich Roberts reports: "We have tried ourselves to detect activity with this gene product and cannot detect any methyltransferase activity. In our case we used antibodies able to detect N6-methyladenine or N4 methylcytosine in DNA. The ones we have are very sensitive and should have been able to detect 5 methyl groups in the whole E. coli chromosome. Nothing was detected in an over expressing strain."For additional information see E. coli restriction-modification system and the NEB technicalinformation on methylation.Commonly used strainsAG1endA1 recA1 gyrA96 thi-1 relA1 glnV44 hsdR17(r K- m K+)AB1157thr-1, araC14, leuB6(Am), Δ(gpt-proA)62, lacY1, tsx-33, qsr'-0, glnV44(AS), galK2(Oc), LAM-, Rac-0, hisG4(Oc), rfbC1, mgl-51, rpoS396(Am), rpsL31(strR), kdgK51, xylA5, mtl-1, argE3(Oc), thi-1Bachmann BJ: Derivation and genotypes of some mutant derivatives of Escherichia coli K-12.Escherichia coli and Salmonella typhimurium. Cellular and Molecular Biology (Edited by: F C Neidhardt J L Ingraham KB Low B Magasanik M Schaechter H E Umbarger). Washington, D.C., American Society for Microbiology 1987, 2:1190-1219.See CGSC#1157BL21E. coli B F- dcm ompT hsdS(r B- m B-) gal [malB+]K-12(λS)The "malB region" was transduced in from the K-12 strain W3110 to make the strain Mal+λS. See Studier et al. (2009) J. Mol. Biol. 394(4), 653 for a discussion of the extent of the transfer.Stratagene E. coli Genotype StrainsBL21(AI)F– ompT gal dcm lon hsdS B(r B- m B-) araB::T7RNAP-tetAan E. coli B strain carrying the T7 RNA polymerase gene in the araB locus of the araBAD operon q.Transformed plasmids containing T7 promoter driven expression are repressed until L-arabinose induction of T7 RNA polymerase.Derived from BL21.See the product page for more information.Brian Caliendo (Voigt lab) reported trouble getting the Datsenko and Wanner (2000) plasmid pCP20 to transform into this strain, when other strains transformed fine. Cause is unknown.BL21(DE3)F– ompT gal dcm lon hsdS B(r B- m B-) λ(DE3 [lacI lacUV5-T7 gene 1 ind1 sam7 nin5])an E. coli B strain with DE3, a λ prophage carrying the T7 RNA polymerase gene and lacI qTransformed plasmids containing T7 promoter driven expression are repressed until IPTG induction of T7 RNA polymerase from a lac promoter.Derived from B834 (Wood, 1966) by transducing to Met+.See the original Studier paper or the summary in Methods in Enzymology for more details.Whole genome sequence available [1]BL21 (DE3) pLysSF- ompT gal dcm lon hsdS B(r B- m B-) λ(DE3) pLysS(cm R)pLysS plasmid chloramphenicol resistant; grow with chloramphenicol to retain plasmidChloramphenicol resistantThe pLysS plasmid encodes T7 phage lysozyme, an inhibitor for T7 polymerase which reduces and almost eliminates expression from transformed T7 promoter containing plasmids when not induced.see Moffatt87 for details of pLysS and pLysE plasmidsBNN93F- tonA21 thi-1 thr-1 leuB6 lacY1 glnV44 rfbC1 fhuA1 mcrB e14-(mcrA-) hsdR(r K-m K+) λ-Some C600 strains are really BNN93BNN97BNN93 (λgt11)A λgt11 lysogen producing phage at 42CBW26434, CGSC Strain # 7658Δ(araD-araB)567, Δ(lacA-lacZ)514(::kan), lacIp-4000(lacI q), λ-, rpoS396(Am)?, rph-1, Δ(rhaD-rhaB)568, hsdR514This information is from a printout sent by the E. coli Genetic Stock Center with the strain.B.L. Wanner strainrph-1 is a 1bp deletion that results in a frameshift over last 15 codons and has a polar effect on pyrE leading to suboptimal pyrimidine levels on minimal medium. (Jensen 1993 J Bact. 175:3401)Δ(araD-araB)567 was formerly called ΔaraBAD AH33 by Datsenko and WannerAm = amber(UAG) mutationReference: Datsenko and Wanner, 2000, PNAS, 97:6640NOTE:This promoter driving the expression of lacI was sequenced in this strain using a primer in mhpR (upstream of lacI) and a primer in the opposite orientation in lacI. The lac promoter was found to be identical to wildtype. Thus, the -35 sequence was GCGCAA not GTGCAA as expected with lacI q.Therefore this strain (or at least the version obtained from the E. coli Genetic Stock Center) does NOT appear to be lacI q. According to Barry Wanner, this is an unexpected result. -Reshma 13:19, 5 May 2005 (EDT)"We have now confirmed that BW25113, BW25141, and BW26434 are all lacI+, and not lacI q. We thank you for alerting us to the error with respect to BW26434. Apparently, the lacI region was restored to wild-type in a predecessor of BW25113." (from Barry Wanner November 18, 2005) The genotype has been corrected at the CGSCC600F- tonA21 thi-1 thr-1 leuB6 lacY1 glnV44 rfbC1 fhuA1 λ-There are strains circulating with both e14+(mcrA+) and e14-(mcrA-)General purpose hostSee CGSC#3004References: Appleyard, R.K. (1954) Genetics 39, 440; Hanahan, D. (1983) J. Mol. Biol. 166, 577.C600 hflA150 (Y1073, BNN102)F- thi-1 thr-1 leuB6 lacY1 tonA21 glnV44 λ- hflA150(chr::Tn10)host for repressing plaques of λgt10 when establishing cDNA librariesReference Young R.A. and Davis, R. (1983) Proc. Natl. Acad. Sci. USA 80, 1194.Tetracycline resistance from the Tn10 insertionCSH50F- λ- ara Δ(lac-pro) rpsL thi fimE::IS1See CGSC#8085References: Miller, J.H. 1972. Expts.in Molec.Genetics, CSH 0:14-0; Blomfeld et al., J.Bact. 173: 5298-5307, 1991.D1210HB101 lacI q lacY+DB3.1F- gyrA462 endA1 glnV44 Δ(sr1-recA) mcrB mrr hsdS20(r B-, m B-) ara14 galK2 lacY1 proA2rpsL20(Sm r) xyl5 Δleu mtl1useful for propagating plasmids containing the ccdB operon.gyrA462 enables ccdB containing plasmid propagationstreptomycin resistantappears to NOT contain lacI (based on a colony PCR) --Austin Che 16:16, 18 June 2007 (EDT)<biblio>1. Bernard-JMolBiol-1992 pmid=13243242. Miki-JMolBiol-1992 pmid=1316444</biblio>DH1endA1 recA1 gyrA96 thi-1 glnV44 relA1 hsdR17(r K- m K+) λ-parent of DH5αAn Hoffman-Berling 1100 strain derivative (Meselson68)more efficient at transforming large (40-60Kb) plasmidsnalidixic acid resistantReference: Meselson M. and Yuan R. (1968) Nature 217:1110 PMID 4868368.DH5αF- endA1 glnV44 thi-1 recA1 relA1 gyrA96 deoR nupG Φ80d lacZΔM15 Δ(lacZYA-argF)U169,hsdR17(r K- m K+), λ–An Hoffman-Berling 1100 strain derivative (Meselson68)Promega also lists phoAnalidixic acid resistantReferences:FOCUS (1986) 8:2, 9.Hanahan, D. (1985) in DNA Cloning: A Practical Approach (Glover, D.M., ed.), Vol. 1, p. 109, IRL Press, McLean, Virginia.Grant, S.G.N. et al. (1990) Proc. Natl. Acad. Sci. USA 87: 4645-4649 PMID 2162051.Meselson M. and Yuan R. (1968) Nature 217:1110 PMID 4868368.DH10B (Invitrogen)F- endA1 recA1 galE15 galK16 nupG rpsL ΔlacX74 Φ80lacZΔM15 araD139 Δ(ara,leu)7697 mcrAΔ(mrr-hsdRMS-mcrBC) λ-suitable for cloning methylated cytosine or adenine containing DNAan MC1061 derivative (Casadaban80). Prepare cells for chemical transformation with CCMB80 bufferblue/white selectionWhile DH10B has been classically reported to be galU galK, the preliminary genome sequence for DH10B indicates that DH10B (and by their lineage also TOP10 and any other MC1061 derivatives) is actually galE galK galU+. Dcekiert 16:37, 23 January 2008 (CST)Genome sequence indicates that DH10B is actually deoR+. Presumably TOP10 and MC1061 are also deoR+.Streptomycin resistantReferences:Casdaban, M. and Cohen, S. (1980) J Mol Biol 138:179 PMID 6997493.Grant, S.G.N. et al. (1990) Proc. Natl. Acad. Sci. USA 87: 4645-4649 PMID 2162051.E. coli Genetic Stock Center, MC1061 RecordDH10B Genome Sequencing Project, Baylor College of MedicineComplete sequence is available, see Durfee08, PMID 18245285.DH12S (Invitrogen)mcrA Δ(mrr-hsdRMS-mcrBC) φ80d lacZΔM15 ΔlacX74 recA1 deoR Δ(ara, leu)7697 araD139 galU galK rpsL F' [proAB+ lacI q ZΔM15]host for phagemid and M13 vectorsuseful for generating genomic libraries containing methylated cytosine or adenine residuesstreptomycin resistantReferences: Lin, J.J., Smith, M., Jessee, J., and Bloom, F. (1991) FOCUS 13, 96.; Lin, J.J., Smith, M., Jessee, J., and Bloom, F. (1992) BioTechniques 12, 718.DM1 (Invitrogen)F- dam-13::Tn9(Cm R) dcm- mcrB hsdR-M+ gal1 gal2 ara- lac- thr- leu- tonR tsxR Su0Host for pBR322 and other non-pUC19 plasmids; useful for generating plasmids that can be cleaved with dam and dcm sensitive enzymesChloramphenicol resistantPromega lists as F' not F-Reference: Lorow-Murray D and Bloom F (1991) Focus 13:20E. cloni(r) 5alpha (Lucigen)fhuA2Δ(argF-lacZ)U169 phoA glnV44 Φ80 Δ(lacZ)M15 gyrA96 recA1 relA1 endA1 thi-1 hsdR17Common cloning strain.E. cloni(r) 10G (Lucigen)F- mcrA Δ(mrr-hsd RMS-mcr BC) end A1 rec A1 Φ80dlac ZΔM15 Δlac X74 ara D139 Δ(ara,leu)7697 gal U gal K rps L nup G λ- ton ACommon cloning strain.Resistant to phage T1.E. cloni(r) 10GF' (Lucigen)[F´ pro A+B+ lac Iq ZΔM15::Tn10 (TetR)] /mcr A Δ(mrr-hsd RMS-mcr BC) end A1 rec A1 Φ80d lac ZΔM15Δlac X74 ara D139 Δ(ara, leu)7697 gal U gal K rps L nup Gλ ton AStrain for cloning and single-strand DNA production.E. coli K12 ER2738 (NEB)F´proA+B+ lacIq Δ(lacZ)M15 zzf::Tn10(TetR)/ fhuA2 glnV Δ(lac-proAB) thi-1 Δ(hsdS-mcrB)5 Phage propagation strainAlso available from Lucigen Corporation.ER2566 (NEB)F- λ- fhuA2 [lon] ompT lacZ::T7 gene 1 gal sulA11 Δ(mcrC-mrr)114::IS10 R(mcr-73::miniTn10-TetS)2 R(zgb-210::Tn10)(TetS) endA1 [dcm]Host strain for the expression of a target gene cloned in the pTYB vectors.Carry a chromosomal copy of the T7 RNA polymerase gene inserted into lacZ gene and thus under the control of the lac promoter. In the absence of IPTG induction expression of T7 RNA polymeraseis suppressed by the binding of lac I repressor to the lac promoter.Deficient in both lon and ompT proteases.ER2267 (NEB)F´ proA+B+ lacIq Δ(lacZ)M15 zzf::mini-Tn10 (KanR)/ Δ(argF-lacZ)U169 glnV44 e14-(McrA-) rfbD1? recA1 relA1? endA1 spoT1? thi-1 Δ(mcrC-mrr)114::IS10Commonly used for titering M13 phage because of the strain's F' plasmid, which carries KanR, and its slow growth, which promotes easy visualization of plaques.HB101F- mcrB mrr hsdS20(r B- m B-) recA13 leuB6 ara-14 proA2 lacY1 galK2 xyl-5 mtl-1 rpsL20(Sm R) glnV44λ-Please note that different sources have different genotypes so treat this information with caution.From a GIBCO BRL list of competent cells.Hybrid of E. coli K12 and E. coli B (but 98% K strain AB266 according to Smith et al.)Host for pBR322 and many plasmidsSigma lists the deletion Δ(gpt,proA). Check this.Promega does not list F-, mcrB, or mrrStreptomycin resistantReferences:Boyer, H.W. and Roulland-Dussoix, D. (1969) J. Mol. Biol. 41, 459.Smith, M., Lorow, D., and Jessee, J. (1989) FOCUS 11, 56 - pdf version from InvitrogenLacks S and Greenberg JR (1977) J Mol Biol 114:153.HMS174(DE3)F- recA1 hsdR(rK12- mK12+) (DE3) (Rif R)HMS174 strains provide the recA mutation in a K-12 background. Like BLR, these strains may stabilize certain target genes whose products may cause the loss of the DE3 prophage.DE3 indicates that the host is a lysogen of lDE3, and therefore carries a chromosomal copy of the T7 RNA polymerase gene under control of the lacUV5 promoter. Such strains are suitable forproduction of protein from target genes cloned in pET vectors by induction with IPTG.High-Control(tm) BL21(DE3) (Lucigen)F– ompT gal dcm hsdS B(r B- m B-) (DE3)/Mini-F lacI q1(Gent r)The HI-Control BL21(DE3) cells contain a single-copy BAC plasmid harboring a specially engineered version of the lacI q1 repressor allele. The lacI q1 allele expresses ~170-fold more lac repressor protein than the wild-type lacI gene.The increased pool of lac repressor in HI-Control BL21(DE3) cells maintains tight control over the expression of T7 RNA polymerase from the lacUV5 promoter, reducing leaky expression of genes cloned under a T7 promoter.an E. coli B strain with DE3, a λ prophage carrying the T7 RNA polymerase gene and lacI qTransformed plasmids containing T7 promoter driven expression are repressed until IPTG induction of T7 RNA polymerase from a lac promoter.High-Control(tm) 10G (Lucigen)F- mcrA Δ(mrr-hsd RMS-mcr BC) end A1 rec A1 Φ80dlac ZΔM15 Δlac X74 ara D139 Δ(ara,leu)7697 gal U gal K rps L nup G λ- ton A/Mini-F lacI q1(Gent r)The HI-Control 10G cells contain a single-copy BAC plasmid harboring a specially engineered version of the lacI q1 repressor allele. The lacI q1 allele expresses ~170-fold more lac repressor protein than the wild-type lacI gene.For stable cloning of T7 protein expression plasmids.Resistant to phage T1.IJ1126E. coli K-12 recB21 recC22 sbcA5 endA gal thi Su+ Δ(mcrC-mrr)102::Tn10See Endy:IJ1126IJ1127IJ1126 lacUV5 lacZ::T7 gene1-KnrSee Endy:IJ1127JM83rpsL ara Δ(lac-proAB) Φ80dlacZΔM15Sigma lists thi. Check this.streptomycin resistantJM101glnV44 thi-1 Δ(lac-proAB) F'[lacI q ZΔM15 traD36 proAB+]host for M13mp vectorsrecA+, r K+original blue/white cloning strainhas all wt restriction systemsReferences: Messing, J. et al. (1981) Nucleic Acids Res. 9, 309; Yanisch-Perron, C., Vieira, J., and Messing, J. (1985) Gene 33, 103.JM103endA1 glnV44 sbcBC rpsL thi-1 Δ(lac-proAB) F'[traD36 proAB+ lacI q lacZΔM15]streptomycin resistantReferences: Hanahan, D. (1983) J. Mol. Biol. 166:557-80.NEB says this strain encodes a prophage encoded EcoP1 endonuclease.Sigma lists (P1) (r K-m K+ rP1+ mP1+)JM105endA1 glnV44 sbcB15 rpsL thi-1 Δ(lac-proAB) [F' traD36 proAB+ lacI q lacZΔM15] hsdR4(r K-m K+)Sigma lists sbcCstreptomycin resistantReferences: Yanisch-Perron, C., Vieira, J., and Messing, J. (1985) Gene 33, 103.JM106endA1 glnV44 thi-1 relA1 gyrA96 Δ(lac-proAB) F- hsdR17(r K-m K+)References: Yanisch-Perron, C., Vieira, J., and Messing, J. (1985) Gene 33, 103.JM107endA1 glnV44 thi-1 relA1 gyrA96 Δ(lac-proAB) [F' traD36 proAB+ lacI q lacZΔM15] hsdR17(R K- m K+) λ-host for M13mp vectorsrecA+, r K+Sigma lists e14- (McrA-)nalidixic acid resistantReferences: Yanisch-Perron, C., Vieira, J., and Messing, J. (1985) Gene 33, 103.JM108endA1 recA1 gyrA96 thi-1 relA1 glnV44 Δ(lac-proAB) hsdR17 (r K- m K+)nalidixic acid resistantdeficient in expression of the lon protease due to IS186 transposon insertion -- J Mairhofer 18:59,24 March 2010 (CET)<biblio>1. Reference pmid=20138928</biblio>JM109endA1 glnV44 thi-1 relA1 gyrA96 recA1 mcrB+ Δ(lac-proAB) e14- [F' traD36 proAB+ lacI q lacZΔM15] hsdR17(r K-m K+)From NEBPartly restriction-deficient; good strain for cloning repetitive DNA (RecA–).Suppresses many amber mutations when glutamine is acceptable but not the S100 or S7 mutations of λ, e.g., λgt11.Can also be used for M13 cloning/sequencing and blue/white screening.Sigma lists e14-nalidixic acid resistantdeficient in expression of the lon protease due to IS186 transposon insertion -- J Mairhofer 18:59,24 March 2010 (CET)From C. Yanisch-Perron, J. Vieira, and J. Messing. Improved M13 phage cloning vectors and host strains: nucleotide sequences of the M13mp18 and pUC19 vectors. Gene, 33(1):103–19, 1985.Some information from Mary Berlyn at the E. coli Genetic Stock Center: One of the reasons the original curator of this collection did not accession the JM109, JM103, etc. strains was because she found it impossible to be sure of the derivation and therefore the details of the genotype. But I think it's safe to assume that the F' in this strain is derived from or similar to F128 which extends from the proBA region through the lac operon. It thus carries the wildtype genes for all loci in that region except those indicated as mutant for the genotype of the F'. So it carries the lacZ (alpha-complementation) deletion lacZ58(M150 and the lacI mutation lacIq, but it has the lacY+ gene also on the F-prime. On the chromosome it lacks all the lac operon genes.NOTE: The promoter driving the expression of lacI was sequenced in this strain using a primer in mhpR (upstream of lacI) and a primer in the opposite orientation in lacI. The lac promoter was found tobe identical to wildtype. Thus, the -35 sequence was GCGCAA not GTGCAA as expected with lacI Q.Therefore this strain (or at least the version we have) does NOT appear to be lacI Q unless there is another copy of lacI elsewhere. This result is somewhat confirmed by the fact that a lacI regulated promoter driving expression of YFP on a medium copy vector does not repress completely. -Reshma 13:48, 5 May 2005 (EDT)JM109(DE3)。

ecoli表达体系E. coli表达体系引言：E. coli（大肠杆菌）是一种常见的细菌，广泛应用于基因工程和蛋白质表达领域。

其独特的表达体系为科学家们在基因工程研究中提供了强大的工具。

本文将介绍 E. coli表达体系及其在蛋白质表达中的应用。

一、E. coli表达体系的基本原理E. coli表达体系是利用大肠杆菌作为宿主细胞来表达外源基因的一种方法。

其基本原理是将目标基因插入到表达载体中，然后将载体转化到E. coli细胞中，通过细胞的代谢和转录机制来实现目标基因的表达。

E. coli表达体系具有高效、简便、经济的特点，因此被广泛应用于基因工程领域。

二、E. coli表达体系的关键组成部分1. 表达载体：表达载体是E. coli表达体系的核心部分，通常由启动子、多克隆位点、选择标记和复制起始子等功能元件组成。

启动子用于启动目标基因的转录，多克隆位点用于插入目标基因，选择标记用于筛选转化成功的细菌，复制起始子用于维持载体的复制。

常用的表达载体有pET、pBAD、pGEX等。

2. 宿主细胞：E. coli细胞是E. coli表达体系的宿主细胞，其具有较高的生长速度和简单的培养条件，能够满足大规模表达的需求。

同时，E. coli细胞也具有较高的遗传稳定性和表达效率，使其成为理想的表达宿主。

3. 外源基因：外源基因是指需要表达的目标基因，可以是来自其他物种的基因序列，也可以是人工设计的合成基因。

外源基因的选择应根据研究目的和需求进行合理设计。

三、E. coli表达体系的应用E. coli表达体系在蛋白质表达领域具有广泛的应用前景。

以下是几个常见的应用领域：1. 重组蛋白表达：利用E. coli表达体系可以高效表达各种重组蛋白，如药物、酶、抗体等。

通过对目标基因的合理设计和优化表达条件，可以实现大规模的蛋白质产量，并且具有较高的纯度和活性。

2. 代谢工程：E. coli表达体系在代谢工程中也发挥着重要的作用。

大肠杆菌基因型及遗传符号说明前言：实验室的一般大肠杆菌拥有4288条基因，每条基因的长度约为950bp，基因间的平均间隔为118bp（基因Ⅷ）。

E.coli基因组中还包含有许多插入序列，如λ-噬菌体片段和一些其他特殊组份的片段，这些插入的片段都是由基因的水平转移和基因重组而形成的，由此表明了基因组具有它的可塑造性。

利用大肠杆菌基因组的这种特性对其进行改造，使其中的某些基因发生突变或缺失，从而给大肠杆菌带来可以观察到的变化，这种能观察到的特征叫做大肠杆菌的表现型(Phenotype)，把引起这种变化的基因构成叫做大肠杆菌的基因型（Genotype）。

具有不同基因型的菌株表现出不同的特性。

分子克隆中常用的大肠杆菌及其遗传标记按Demerec等1966年提出的命名原则，采用的菌株所有的基因都假定处于野生型状态，除非在基因型上另外注明。

大肠杆菌基因型的表示方法（Demerec, et, al. 1966）：一、一般规则：1、根据基因产物或其作用产物的英文名称的第一个字母缩写成3个小写斜体字母来表示。

例如：DNA Adenine Methylase→dam。

2、不同的基因座，其中任何一个突变所产生的表型变化可能相同，其表示方法是在3个小写斜体字母后加上一个斜体大写字母来表示区别。

例如：Recombination→recA、recB、recC。

3、突变位点应通过在突变基因符号后加不同数字表示。

如supE44（sup基因座E的44位突变）。

如果不知道几个等位基因中哪一/几个发生了功能性突变，则用连字符“-”代替大写字母，如trp-31。

4、细菌的基因型中应该包含关于其携带的质粒或附加体的的信息。

这些符号包括菌株携带的质粒或附加体、质粒或附加体上的突变基因座和突变位点。

其基因符号应与基因座的表示符号明显区别，符号的第一个字母大写、不斜体并位于括号内；质粒或附加体上的突变基因座和突变位点的基因符号的表示方法与染色体上突变基因座、突变位点的符号相同。

E.coli Competent CellsHST08 Premium使用说明书Takara Code : D9128包装量E. coli HST08 Premium Competent Cells 100 μl × 10 支Control DNA（pUC19，0.1 ng/μl）10 μl × 1 支保存: -80℃制品说明感受态细胞（Competent Cells）是一种具有摄入外源DNA能力的受容菌，它可以摄取外源的质粒DNA等。

在进行基因重组实验时，使用感受态细胞的转化实验应用十分广泛。

在制作基因文库、重组质粒体以及进行亚克隆实验时，特别是在目的基因含量十分低的情况时，使用高效的感受态细胞显得十分重要。

Takara公司在Hanahan方法的基础上进行了改良，制备出了高效的感受态细胞（都为EK1系列的宿主大肠杆菌）。

GenotypeF-, endA1,supE44,thi-1,recA1,relA1,gyrA96,phoA,Φ80d lacZΔM15,Δ(lacZYA-argF) U169,Δ(mrr-hsdRMS-mcrBC),ΔmcrA,λ-细胞种类高效常用宿主E.coli HST08 PremiumHST08 Premium是mrr, hsdRMS, mcrBC, mcrA缺失的菌株，具有很高的转化效率，可用于甲基化质粒的制备，克隆效率比较高。

10 kbp以上长片段的连接转化时，可与TaKaRa DNA Ligation Kit LONG（Takara Code：D6024）一起使用，效果很好。

pUC系列质粒、BAC文库等转化都可以使用。

可通过β-半乳糖苷酶的α-互补性，添加X-gal进行蓝白筛选，以挑选阳性克隆。

细胞浓度: 1～2×109 Bacteria/ml质量标准1. 使用1 ng的质粒DNA进行转化时：100 μl E. coli HST08 Premium Competent Cells/ng pUC19 Plasmid进行转化时产生的菌落数＞1×108transformants/μg pUC19 Plasmid。

Cloning & ExpressionGenotypes of Selected E. coli StrainsGenotypes of Selected E. coli StrainsBL21 E. coli B F–ompT gal [E. coli B is naturally dcm and lon] hsdS BBL21(DE3) E. coli B F–ompT gal [E. coli B is naturally dcm and lon] hsdS B with DE3, a λ prophage carrying the T7 RNA polymerase gene and lacI QC600 F– [e14– (McrF–) or e14+ (McrF+)] thr-1 leuB6 thi-1 lacY1 glnV44 rfbD1 fhuA21CJ236 F Δ(HindIII)::cat (Tra+ Pil+ CamR )/ ung-1 relA1 dut-1 thi-1 spoT1 mcrAGC5 F´endA1 hsdR17 (r K–m K+) glnV44 thi-1 recA1 gyrA (Nal r) relA1 Δ(lacIZYA-argF)U169(φ80dlacΔ(lacZ)M15 fhuAGM48 F–thr leu thi lacY galK galT ara fhuA tsx dam dcm glnV44HB101 F–Δ(gpt-proA)62 leuB6 glnV44 ara-14 galK2 lacY1 Δ(mcrC-mrr) rpsL20 (Str r) xyl-5 mtl-1 recA13JM83 F–araΔ(lac-proAB) rpsL (Str r)[φ80 d lacΔ(lacZ)M15] thiJM101 F´traD36 proA+B+ lacI qΔ(lacZ)M15/Δ(lac-proAB) glnV thiJM103 F´traD36 lacIqΔ(lacZ)M15 proA+B+/endA1 glnV sbcBC thi-1 rpsL (Str r) Δ(lac-pro) (P1)(r K–m K+ rP1+ mP1+)JM105 F´traD36 lacIqΔ(lacZ)M15 proA+B+/thi rpsL (Str r) endA sbcB15 sbcC hsdR4 (r K–m K+)Δ(lac-proAB)JM107 F´traD36 lacI qΔ(lacZ)M15 proA+B+/e14–(McrA–) Δ(lac-proAB) thi gyrA96 (Nal r) endA1 hsdR17 (r K– m K+) relA1 glnV44JM109 F´traD36 proA+B+ lacIq Δ(lacZ)M15/Δ(lac-proAB) glnV44 e14- gyrA96 recA1 relA1 endA1 thi hsdR17JM110 F´traD36 lacI qΔ(lacZ)M15 proA+B+IrpsL (Str r) thr leu thi lacY galK galT ara fhuA dam dcm glnV44 Δ(lac-proAB)K802 F– e14- (McrA-) lacY1 or Δ(lac)6 glnV44 galK2 galT22 rfbD1 metB1 mcrB1 hsdR2 (r K–m K+)LE392 F– e14– (McrA–) hsdR514 (r K–m K+) glnV44 supF58 lacY1or Δ(lacIZY)6 galK2 galT22 metB1 trpR55MC1061 F–araD139Δ(ara-leu)7696 galE15 galK16Δ(lac)X74 rpsL (Str r) hsdR2 (r K–m K+) mcrA mcrB1MM294 F–endA1 hsdR17 (r K–m K+) glnV44 thi-1 relA1 rfbD1 spoT1NM477 C600 Δ(hsdMS-mcrB)5 (r K–m K+ McrBC–)NM522 F´proA+B+ lacI qΔ(lacZ)M15/Δ(lac-proAB) glnV thi-1Δ(hsdS-mcrB)5NM554 MC1061 recA13NM621 F–hsdR (r K–m K+) mcrA mcrB glnV44 recD1009RR1 HB101 RecA+χ1776 F–fhuA53 dapD8 minA1 glnV44 Δ(gal-uvrB)40 minB2 rfb-2 gyrA25 (Nal r) thyA142 oms-2 metC65 oms-1 (tte-1) Δ(bioH-asd)29 cycB2 cycA1 hsdR2 (r K– m K+) mcrB1References1. New England Biolabs. E. coli Strain Genotypes./nebecomm/tech_reference/restriction_enzymes/ecoli_genotypes.asp (Oct. 31, 2005)2. Wertman, K.F. et al. (1986) Gene 49, 253–262.3. Yanisch–Perron, C., Viera, J. and Messing, J. (1985) Gene 33, 103–119.4. Sambrook, J., Fritsch, E.F. and Maniatis, T. (1989). Molecular Cloning: A LaboratoryManual, (2nd ed.). Cold Spring Harbor: Cold Spring Harbor Laboratory Press.5. Huynh,T.V. et al. (1985). In D.M. Glover (Ed.), DNA Cloning Vol. 1, (pp. 56–110). Oxford,England: IRL Press Limited.6. Raleigh, E.A. et al. (1988) Nucl. Acids Res. 16, 1563–1575.7. Woodcock, D.M. et al. (1989) Nucl. Acids Res. 17, 3469–3478.8. Raleigh, E.A., Lech, K. and Brent, R. (1989). In F.M. Ausebel et al. (Eds.), Current Protocolsin Molecular Biology (p. 1.4). New York: Publishing Associates and Wiley Interscience.9. Berlyn, M.K.B. (1996). In F.C. Niedhardt et al. (Ed.), Escherichia coli and Salmonella:cellular and molecular biology, (2nd ed.), Vol. 2, (pp. 1715–1902). ASM Press.10. Miller, J.H. (1972). Experiments in Molecular Genetics. Cold Spring Harbor: Cold SpringHarbor Laboratory Press.11. Whittaker, P.A. et al. (1989) Nucl. Acids Res. 16, 6725–6736.12. Murray, N.E. et al. (1977) Mol. Gen. Genet. 150, 53–61.13. Palmer, B.R. and Marinus, M.G. (1994) Gene 143, 1–12.14. Boyer, H.W, and Roulland–Dussoix, D. (1969) J. Mol. Biol. 41, 459.15. Silhavy, T.J. et al. (1984) Experiments with Gene Fusions (pp. xi–xii) Cold Spring Harbor:Cold Spring Harbor Laboratory.16. Bullock, W.O. et al. (1987) BioTechniques 5, 376–378.17. Maurizi, M.R. et al. (1985) J. Bacteriol. 164, 1124–1135.18. Studier, F.W. et al. (1990). In D.V. Goeddel (Ed.), Methods in Enzymology Vol. 185, (pp.60–89). San Diego: Academic Press.19. Kelleher, J. and Raleigh, E.A. (1991) J. Bacteriol. 173, 5220–5223.20. Woodcock, D.M. et al. (1989) Nucl. Acids Res. 17, 3469–3478.21. Palmer, B.R. and Marinus, M.G. (1994) Gene 143, 1–12.22. Yanisch-Perron, C., Viera, J. and Messing, J. (1985) Gene 33, 103–119.23. Messing, J. (1979) Recombinant DNA Technical Bulletin (NIH) 2, 43–48.24. Gough, J. and Murray, N. (1983) J. Mol. Biol. 166, 1–19.25. Baker, T.A. et al. (1984) Proc. Nat. Acad. Sci. USA 81, 6779–6783.26. Grossman, A.D. et al. (1983) Cell 32, 151–15927. Chung, C.H. and Goldberg, A.L. (1981) Proc. Nat. Acad. Sci. USA 78, 4931–4935.28. Straus et al. (1988) Genes Dev. 2, 1851–1858.29. Kowit, J.D. and Goldberg, A.L. (1977) J. Biol. Chem. 252, 8350–8357.30. Silber, K.R. and Sauer R.T. (1994) Mol. Gen. Genet. 242, 237–240.31. Elish et al. (1988) J. Gen. Microbiol. 134, 1355–1364.32. Kunkel, T.A. et al. (1987). In R. Wu and L. Grossman (Eds.), Methods in Enzymology Vol.154, (pp. 367–382). San Diego: Academic Press.TB1 (E.Coli) Any Info HelpfulMichael Benedik bchs1b at Fri Dec 4 02:29:53 EST 1992Previous message: TB1 (E.Coli) Any Info Helpful∙Next message: TB1 (E.Coli) Any Info Helpful∙Messages sorted by:[ date ][ thread ][ subject ][ author ]In article <1992Dec3.182959.10559 at >, dnicker at writes:>>Am looking for genotype and important characteristics of E.Coli Strain>TB1, ref.>Sliger(sp?), S.G. et.al.>m.,169,1016-1020 (1990)>>TB1 is mentioned in this paper, but no reference given, and all >attempts at identifying this strain have failed. Anyone heard of it? >>Thanks in advance for any help you may provide. . .>>Darren Nickerson > D. Phil. Student >Univ. of Oxford >>E-mail: DNICKER at There is a standard strain TB1 used in a lot of molecular biology labs. I don't know whether that is what you have or not becuase other people may have called their strain TB1 also. But the standard strain is an hsdR- derivative (restriction minus) of JM83.genotype should be: F- ara del(lac-pro) rpsL phi80dlacZM15in other words the relevent genotype for you isblue white screen for cloning in pUC and derivatives, F- so no M13, Pro- so needs proline on minimal plates, restriction minus, strep resistant,Some version of TB1 floating out there also have a Tn5 which was used to transduce in the hsdR allele, but the real strain is not supposed to have it. The precursor to TB1 accidentally got released for awhile.---------------------------------------------------------------------- Michael Benedik INTERNET: Benedik at Dept. of Biochemical & Biophysical SciencesUniversity of Houston BITNET: Benedik at uhou。

本试剂盒只能用于科学研究，不得用于医学诊断大肠杆菌宿主残留蛋白（E.coli P）ELISA检测试剂盒使用说明书检测原理试剂盒采用双抗体一步夹心法酶联免疫吸附试验（ELISA）。

往预先包被大肠杆菌宿主残留蛋白（E.coli P）抗体的包被微孔中，依次加入标本、标准品、HRP标记的检测抗体，经过温育并彻底洗涤。

用底物TMB显色，TMB在过氧化物酶的催化下转化成蓝色，并在酸的作用下转化成最终的黄色。

颜色的深浅和样品中的大肠杆菌宿主残留蛋白（E.coli P）呈正相关。

用酶标仪在450nm 波长下测定吸光度（OD 值），计算样品浓度。

样品收集、处理及保存方法1. 血清：使用不含热原和内毒素的试管，操作过程中避免任何细胞刺激，收集血液后，3000转离心10分钟将血清和红细胞迅速小心地分离。

2. 血浆：EDTA、柠檬酸盐或肝素抗凝。

3000转离心30分钟取上清。

3. 细胞上清液：3000转离心10分钟去除颗粒和聚合物。

4. 组织匀浆：将组织加入适量生理盐水捣碎。

3000转离心10分钟取上清。

5. 保存：如果样本收集后不及时检测，请按一次用量分装，冻存于-20℃，避免反复冻融，在室温下解冻并确保样品均匀地充分解冻。

自备物品1.酶标仪（450nm）2.高精度加样器及枪头：0.5-10uL、2-20uL、20-200uL、200-1000uL3.37℃恒温箱操作注意事项1. 试剂盒保存在2-8℃，使用前室温平衡20分钟。

从冰箱取出的浓缩洗涤液会有结晶，这属于正常现象，水浴加热使结晶完全溶解后再使用。

2. 实验中不用的板条应立即放回自封袋中，密封（低温干燥）保存。

3. 浓度为0的S0号标准品即可视为阴性对照或者空白；按照说明书操作时样本已经稀释5倍，最终结果乘以5才是样本实际浓度。

4. 严格按照说明书中标明的时间、加液量及顺序进行温育操作。

5. 所有液体组分使用前充分摇匀。

试剂盒组成名称96孔配置48孔配置备注微孔酶标板12孔×8条12孔×4条无标准品0.3mL*6管0.3mL*6管无样本稀释液6mL 3mL 无检测抗体-HRP 10mL 5mL 无20×洗涤缓冲液25mL 15mL 按说明书进行稀释底物A 6mL 3mL 无底物B 6mL 3mL 无终止液6mL 3mL 无封板膜2张2张无说明书1份1份无自封袋1个1个无注：标准品（S0-S5）浓度依次为：0、5、10、20、40、80 ng/mL试剂的准备20×洗涤缓冲液的稀释：蒸馏水按1：20稀释，即1份的20×洗涤缓冲液加19份的蒸馏水。

大肠杆菌基因型及遗传符号说明前言：实验室的一般大肠杆菌拥有4288条基因，每条基因的长度约为950bp，基因间的平均间隔为118bp（基因Ⅷ）。

E.coli基因组中还包含有许多插入序列，如λ-噬菌体片段和一些其他特殊组份的片段，这些插入的片段都是由基因的水平转移和基因重组而形成的，由此表明了基因组具有它的可塑造性。

利用大肠杆菌基因组的这种特性对其进行改造，使其中的某些基因发生突变或缺失，从而给大肠杆菌带来可以观察到的变化，这种能观察到的特征叫做大肠杆菌的表现型(Phenotype)，把引起这种变化的基因构成叫做大肠杆菌的基因型（Genotype）。

具有不同基因型的菌株表现出不同的特性。

分子克隆中常用的大肠杆菌及其遗传标记按Demerec等1966年提出的命名原则，采用的菌株所有的基因都假定处于野生型状态，除非在基因型上另外注明。

大肠杆菌基因型的表示方法（Demerec, et, al. 1966）：一、一般规则：1、根据基因产物或其作用产物的英文名称的第一个字母缩写成3个小写斜体字母来表示。

例如：DNA Adenine Methylase→dam。

2、不同的基因座，其中任何一个突变所产生的表型变化可能相同，其表示方法是在3个小写斜体字母后加上一个斜体大写字母来表示区别。

例如：Recombination→recA、recB、recC。

3、突变位点应通过在突变基因符号后加不同数字表示。

如supE44（sup基因座E的44位突变）。

如果不知道几个等位基因中哪一/几个发生了功能性突变，则用连字符“-”代替大写字母，如trp-31。

4、细菌的基因型中应该包含关于其携带的质粒或附加体的的信息。

这些符号包括菌株携带的质粒或附加体、质粒或附加体上的突变基因座和突变位点。

其基因符号应与基因座的表示符号明显区别，符号的第一个字母大写、不斜体并位于括号内；质粒或附加体上的突变基因座和突变位点的基因符号的表示方法与染色体上突变基因座、突变位点的符号相同。

e.coli stable基因型什么是E.coli stable基因型？E.coli（大肠杆菌）是一种常见的细菌，存在于人类和其他动物的肠道中。

然而，有些E.coli株变异并产生了不同的基因型。

其中一种基因型被称为E.coli stable基因型，指的是一组具有稳定性的基因序列，这些基因序列在E.coli的遗传表达中起着重要的作用。

E.coli stable基因型的特征E.coli stable基因型通常包含多个基因，这些基因控制了细菌的生长、代谢、蛋白质合成和DNA复制等重要过程。

这些基因的稳定性是指它们在E.coli细菌群体中的相对保持不变的性质。

这意味着无论环境条件如何变化，这些基因的序列和表达模式都比较稳定。

E.coli stable基因型的重要性E.coli stable基因型的稳定性对细菌的适应性和生存能力至关重要。

这些基因控制了许多重要的生物学过程，如能量代谢、营养物质利用、生长速率、抗生素耐药性等。

当环境条件变化时，只有稳定的基因型能够确保细菌适应并生存下来。

另一个值得注意的特点是，E.coli stable基因型在不同株系的E.coli中也保持稳定。

这意味着这些基因的稳定性可能与细菌的物种和亚种特定特征有关。

通过通过比较不同E.coli株系的基因型，科学家可以更好地了解这些基因在细菌中的功能和重要性。

维持E.coli stable基因型的机制E.coli稳定基因型的维持依赖于多个机制。

首先，DNA复制和修复过程中的一系列酶和蛋白质确保了基因型的稳定性。

这些酶和蛋白质有助于避免或修复DNA序列中的错误和突变。

其次，特定的信号通路和基因表达调控机制也参与了E.coli维持基因型稳定性的过程。

这些机制保证了基因在适应环境变化时的合适表达。

应用和研究前景E.coli stable基因型的研究对于理解这种细菌的生物学特性以及应对抗药性的挑战具有重要意义。

由于E.coli是导致许多胃肠道感染的主要致病菌之一，研究人员希望通过研究稳定基因型，了解这些基因在感染过程中的作用，以便开发新的治疗策略。