# 830: R2A MEDIUM ## Main sol. 830 0.5 g Yeast extract 0.5 g Proteose peptone (Difco no. 3) 0.5 g Casamino acids 0.5 g Glucose 0.5 g Starch (soluble) 0.3 g Na-pyruvate 0.3 g K2HPO4 0.05 g MgSO4 x 7 H2O 15 g Agar 1000 ml Distilled water 1. Final pH 7.2; adjust with crystalline K2HPO4 or KH2PO4 before adding agar. Add agar, heat medium to boiling to dissolve agar, and autoclave for 15 min at 121°C.