Team:Goettingen/protocol Colony

E.coli cracking

Solutions:
     Crack buffer: 100 µl 2 M NaOH (0.16 g/ 2 ml), 50 µl 10% SDS, 0,2 g Glc, add 1 ml H2O
     Crack dye: 150 µl 4 M KCl (0.597 g / 2 ml), 50 µl Loading-dye
1. Pick bacterial colonies to a large size (2-3 mm)
2. Using a sterile tip, transfer a small quantity of the colony to 1.5 ml cup containing 10 µL 10 mM EDTA add 25 µl Crack buffer
3. Incubate the tube at 70 °C 5 minutes
4. Cool down on ice.
5. Add 2 µl Crack dye and incubate 10 min on ice
6. Spin down 10 minutes 14K rpm
7. Run a gel with 25 µl of the supernatant. (Note: it is difficult to apply the mixture because of its viscosity. Loading the mixtures into empty wells rather than the wells filled with buffer and pouring buffer thereafter may give better result.)
8. Under UV-illuminator, plasmid DNA should be visible between E. coli genomic DNA (20-30 kb) and low molecular weight RNAs.

Yeast colony PCR

1. Aliquot 20 µl NaOH (20 mM) into 1.5 ml tubes
2. Pick colonies (use pipet tips) into the NaOH
3. Incubate at 95°C for ~ 45 minutes
4. Centrifuge at max speed for 10 minutes
5. Use 5 µl of supernatant as template in a (50 µl) PCR.

Auto-activity Test

plating the yeast strains transformed with the bait construct onto SC double drop-out plates lacking Trp and His
supplemented with 3-AT (3-5 mM) to suppress the background leakage of the Gal4-dependent promoters
in case of growth on these control plates, the 3-AT concentration can be increased up to 50-100 mM