UCL London/Protocol/Transformation
From 2009.igem.org
Transformation
- Materials:
- Plasmids DNA
- Competent E.coli
- NZY Medium
- LB buffer
- Ampicllin, Kanamycin, Tetracycline
- Agar Plates
- Eppendorf
- Method 1:
- Add 5µL ice-cold plasmid DNA into the competent E.coli on ice.
- Incubate on ice for 30 min. (minimum) Incubate at 42°C for 45 sec.
- Incubate on ice for 2 min. (minimum)
- Add 300µL of NZYX medium.
- Incubate with shaking at 37°C for 1 hr.
- Spin the incubated E.coli suspension for 3min at maximum speed. (Optional)
- Discard about half of the liquid, and then re-suspend the E.coli solution. (Optional)
- Spread the suspension onto selective agar plates.
- Incubate at 37°C overnight.
- Pick a colony into 2ml selective LB (Add 100µL antibiotic to 50mL LB medium). Incubate 37°C in shaker overnight
- Method 2:
- Using the puch tool, puch out the appropriate DNA. Clean the tool between punches.
- Soak the spots in 5µL of TE that has been warmed to 50ºC for 20 minutes. At this time take the competent cells from the -80º freezer and start defrosting on ice.
- Add 2µL of DNA in TE to 50µL of competent cells (TOP10)
- Allow the DNA and competent cells to sit on ice for 30 minutes
- Heat shock at 42ºC for 60 sec in water bath.
- Recover on ice for 5 min.
- Add 200 µL SOC media.
- Incubate at 37ºC for 2 hr while the tubes are rotating.
- Centrifuge and leave about 100 µL liquid; hence, resuspend the E.coli suspension.
- Plate 250µL on an LB plate with the appropriate antibiotic.