YPAD

Bacto-peptone, 20 g

bacto-yeast extract, 10 g

glucose, 20 g

Adenine sulfate, 40 mg

Bacto-agar, 20 g

Distilled H₂O, 1000 ml

YPAD is a complex medium used for the preparation of slants. The adenine is added to inhibit the reversion of ade1 and ade2 mutants.

Dissolve the medium in a boiling-water bath. Dispense 1.5-ml portions with an automatic pipettor into 1-dram vials. Screw on caps loosely and autoclave the vials. After autoclaving, incline the rack so that the agar is just below the neck of the vial. Tighten the caps after 1-2 days.