18 July 2013
From 2013.igem.org
TOPO TA cloning was performed for two PCR products, aptamers from SELEX cycle 11: one is with A-overhangs and another is without overhangs.
- Ligation reaction (7ul for 1 tube):
- Fresh PCR product 3ul
- Salt solution 1ul
- Water 2ul
- TOPO Vector 1ul
- Transformation
- Put 2 tubes of JM109 competent cells on ice (100ul each)
- Tap tubes to resuspend cells
- Add 7ul of ligation reaction to each cell tube, tap
- Incubate on ice for 30 min
- Heat-shock at 37degC for 45 seconds
- Immediately put on ice for 2 min
- Add 450ul of SOC medium and incubate at 37degC at 230rpm for 1 hour
- Plating
- Prepare 8 flasks for incubation of transformed cells in LB broth (4 for each PCR product)
- Label: Ampicillin, Kanamycin, Control and Blank
- Add 5ml of LB broth to each flask
- Add to flasks, labeled for Ampicillin, 2.5ul of 50ug/ml Ampicillin
- Add to flasks, labeled for Kanamycin, 0.25ul of 1g/ml Kanamycin
- Add 40ul of 40mg/ml X-gal to each flask
- Add 40ul of 100mM IPTG
- Add 50ul of transformed cells to each except blanks
In addition, we plated cells that contain product with A-overhangs on 2 plates: with ampicillin and with kanamycin. We left everything for incubation overnight.