BL21(DE3) 感受態細胞
BL21(DE3) Chemically Competent Cell   
規格 ：100ul*10  

介紹：
基 因 型F- ompT hsdSB(rB- mB- ) gal dcm(DE3)簡 要 說 明High5TM系列 BL21（DE3）感受態細胞用于高效表達克隆于含有噬菌體T7啟動子的表達載體(如pET系列)的基因。λ噬菌體DE3區含有T7噬菌體RNA聚合酶，該區整合于BL21的染色體上，所以稱為BL21(DE3)。可同時表達T7 RNA聚合酶和大腸桿菌RNA聚合酶，用于pET系列，pGEX，pMAL等質粒的蛋白表達。High5TM系列BL21（DE3） 感受態細胞由特殊工藝制作，經pUC19質粒檢測轉化效率達108cfu/μg。

操 作 說 明
1.取100μl冰上融化的BL21（DE3）感受態細胞，加入目的質粒并輕輕混勻，冰上靜置25分鐘。
2.42℃水浴熱激90秒，迅速放回冰上并靜置2分鐘，晃動會降低轉化效率。
3.向離心管中加入700μl不含抗生素的無菌培養基（2YT或LB），混勻后37℃，200rpm復蘇60分鐘。
4.5000rpm離心一分鐘收菌,留取100μl左右上清輕輕吹打重懸菌塊并涂布到含相應抗生素的2YT或LB培養基上。
5.將平板倒置放于37℃培養箱過夜培養。

注 意 事 項
1.感受態細胞最好在冰上融化。
2.混入質粒時應輕柔操作。
3.轉化高濃度的質粒可相應減少最終用于涂板的菌量。
4.誘導時，IPTG濃度可選（0.1-2mM均可）。
5.為獲得需要量的蛋白，最佳誘導時間，溫度，IPTG濃度需實驗者優化。

Sample Induction Protocol (for reference only)1.Inoculate a single colony from a freshly streaked plate into 5 ml of LB medium containing the appropriate antibiotic for the plasmid and host strain.2.Incubate with shaking at 200 rpm at 37℃ overnight. 3.Inoculate 50 ml of LB medium containing the appropriate antibiotic with 0.5 ml of the overnight culture prepared in step 2(use the 500 ml triangular flask as the container would be better).4.Incubate with shaking at 150 rpm at 37℃ until the OD 600 reaches 0.5-0.8.5.(Optional)Pipet 1ml of  the cultures into clean microcentrifuge tubes and  place the tubes on ice until needed  for gel analysis or storage at  -20℃. These will serve as the non-induced control samples.     6.Add IPTG to a final concentration of 1 mM.  Optimal time for induction of the target protein may vary from 2-16 hours, depending on the protein.7.Incubate with shaking at 120 rpm at 37℃ for 3-4 hours. To determine the optimal time for induction of the target protein, it is recommended that a time course experiment be performed varying the induction from 2-16 hours.8.Place the culture on ice for 10 minutes. Harvest cells by centrifugation at 5,000 x g for 101.minutes at 4℃.9.Remove the supernatant and store the cell pellet at -20℃ (storage at lower temperatures is also acceptable). IPTGPrepare a 1 M solution of IPTG (Isopropyl-β-D-thiogalactoside; Isopropyl-β-D-thiogalactopyranoside) bydissolving 2.38 g of IPTG in dd water and adjust the final volume to 10 ml. Filter sterilize before use.

此產品需要干冰運輸發貨，會根據路途及包裝大小收取一定的干冰運費。

儲存條件： -80℃