Transformation of Budding Yeast:

1. Grow up 15 ml culture overnight
2. Harvest cells by centrifuging 5min at 4000 xg at room temperature. Resuspend in ddH₂0. Spin and remove supernatant
3. Transfer to smaller centrifuge tube and pellet cells 5min at 5000-6000rpm
4. Resuspend in 1.5ml buffered lithium solution freshly prepared

1 vol 10 x TE buffer pH 7.5

1 vol 10 x lithium acetate stock solution

8 vol sterile water

5. Incubate 1 hour at 30⁰C
6. Mix 200mg carrier sperm DNA with about 5mg of transforming DNA.
7. Use 200ml of yeast suspension to each microcentrifuge tube.
8. Add 1.2 ml of PEG solution

8 vol 50% PEG

1 vol 10 x TE pH 7.5

1 vol 10 x lithium acetate stock solutions

9. Shake at 30⁰C for 30 minutes
10. Heat shock 15 minutes at 42⁰C.
11. Spin down cells and resuspend yeast in 200ml of 1 x TE buffer and spread on plate.
12. Incubate at 30⁰C till transformants appear.

10 X lithium acetate: 1 M lithium acetate pH 7.5

10 X TE buffer ph 7.5: