To make frozen stocks of yeast strains:
-Use sterile technique and sterile solutions throughout this method.-
1. Grow a starter culture at 30 with shaking (250 rpm) until
it reaches saturation.
2. In a 1.8 ml cryotube, mix 0.5 ml of the saturated culture
with 0.5 ml of YPD containing 20% glycerol.
3. Flash freeze the tube in liquid nitrogen and store at -80.
4. To use, chip out a few pieces of the frozen stock using a
sterile pipette tip or sterile toothpick and streak onto a plate
containing the appropriate solid media.
5. Allow the yeast to grow at 30 until colonies appear (2-6 days).