Product Specification
XL1-Blue:100μl/tube
pUC19 (control vector，10pg/μl): 10μl
storage condition（Guarantee period）: -80℃（6 months）
Genotype
recA1 endA1 gyrA96 thi-1 hsdR17 supE44 (rk-,mk+), relA1 lac [F' proAB lacIqZ∆M15: Tn10 (TetR)]
Product Description
The XL1-Blue strain ensures stable replication of high copy plasmids, and the mutations of recA1 and endA1 facilitate the extraction of stable DNA and high purity plasmid DNA. The hsdR17 mutation results in the deletion of the EcoK endonuclease system, which enhances the stability and extraction quality of the exogenous DNA. The presence of lacIqZΔM15 allows the XL1-Blue strain to be used for blue and white spot screening. This strain has tetracycline resistance. The XL1-Blue competent cells were prepared by a special process, and the pUC19 plasmid detected a transformation efficiency of >109 cfu/μg DNA.
Operation Method
1. XL1-Blue competent cells are taken out at -80 °C, quickly inserted into ice, and after 5 minutes, the bacteria pieces are thawed, the target DNA (plasmid or ligation product) is added and the EP tube bottom is gently mixed by hand (avoid using the micropipette to mix the contents) and place the EP tube in ice for 25 minutes.
2. Heat at 42 °C for 45 seconds, quickly put it back on the ice and let it stand for 2 minutes. Shaking will reduce the conversion efficiency.
3. Add 700 μl of antibiotic-free sterile medium (2YT or LB) to the tube and mix for 37 minutes at 37 ° C and 200 rpm on the shaker.
4. Centrifuge at 5000 rpm for one minute, and take about 100 μl of supernatant. Gently blow and resuspend the pellet and apply it to 2YT or LB medium containing the corresponding antibiotic.
5. Place the plate upside down in a 37 ° C incubator for overnight incubation.
Attention
1. Competent cells should be slowly thawed in ice. Insert the target DNA within 8 minutes of insertion into ice. Do not leave it in ice for too long. Long-term storage will reduce conversion efficiency.
2. Gently handle and mix the plasmids or ligation products.
3. Conversion of high concentrations of plasmids or high efficiency ligation products can correspondingly reduce the amount of bacteria ultimately used for plating.
