JM108 Escherichia coli Strains
Alternative name JM108 Escherichia coli Strains,JM108,Escherichia coli
Packing 100ul Storage at -20鈩?glycerol/ -80鈩?/span>
Strains Resistance None of resistance
Culture Medium LB
Condition 37鈩?,under the aerobic conditions
JM108 Escherichia coli Strains Genotype
endA1 recA1 gyrA96 thi-1 relA1 glnV44 Δ(lac-proAB) hsdR17 (rK- mK+)
JM108 Escherichia coli Strains Description
1.Nalidixic acid resistant.
2.Deficient in expression of the lon protease due to IS186 transposon insertion.
JM108 Escherichia coli Strains Protocol
1.Culture the E. coli JM108
Take the single colony of E. coli JM108 from LB plate and inoculated in 3-5ml LB liquid medium.Shaking at 37 鈩?for about 12 hours . JM108 suspension was inoculated in 100 ml LB liquid medium at the ratio of 1:100-1:50, then incubated at 37 鈩?for 2-3 hours until OD600 = 0.5.
2銆?Preparation of competent cells (CaCl2 method)
1. Transfer the culture medium into a centrifuge tube, place it on ice for 10 minutes, and then centrifuge it at 3000g at 4 鈩?for 10 minutes.
2. Discard the supernatant, gently suspend the cells with 10 ml of pre cooled 0.05 mol / L CaCl2 solution, place them on ice for 15-30 minutes, and centrifuge them at 3000g at 4 鈩?for 10 minutes.
3. Discard the supernatant, add 4ml pre cooled 0.05mol/l CaCl2 solution containing 15% glycerol, gently suspend the cells, and place on ice for a few minutes to form the competent cells suspension.
4.Stored at - 70 鈩?for half a year.