Yeast extract 0.50 g, Proteose Peptone (Difco no. 3) 0.50 g, Casamino acids 0.50 g, Glucose 0.50 g, Soluble starch 0.50 g, Na-pyruvate 0.30 g, K2HPO4 0.30 g, MgSO4 x 7 H2O 0.05 g, Na2CO3 5.0 g, Agar 15.00 g, Distilled water 1000.00 ml 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.