# 479: METHANOHALOPHILUS MEDIUM ## Main sol. 479 87 g NaCl 1.5 g KCl 6 g MgCl2 x 6 H2O 0.4 g CaCl2 x 2 H2O 1 g NH4Cl 0.4 g K2HPO4 x 3 H2O 10 ml **Modified Wolin's mineral solution** 2 g Yeast extract (OXOID) 2 g Trypticase peptone (BD BBL) 0.5 ml Sodium resazurin (0.1% w/v) 1.5 g Na2CO3 2 g Trimethylamine-HCl 0.2 g 2-Mercaptoethanesulfonate (coenzyme M) 0.25 g Na2S x 9 H2O 1000 ml Distilled water 1. Dissolve ingredients except carbonate, trimethylamine, coenzyme M and sulfide. Sparge medium with 80% N2 and 20% CO2 gas mixture for 30 - 45 min to make it anoxic, then dispense under same gas atmosphere into anoxic Hungate-type tubes or serum vials and autoclave. Add trimethylamine, coenzyme M and sulfide from sterile anoxic stock solutions prepared under 100% N2 gas and carbonate from a sterile anoxic stock solution prepared under 80% N2 and 20% CO2 gas mixture. Adjust pH of complete medium to 7.0 - 7.2, if necessary. ## Modified Wolin's mineral solution 1.5 g Nitrilotriacetic acid 3 g MgSO4 x 7 H2O 0.5 g MnSO4 x H2O 1 g NaCl 0.1 g FeSO4 x 7 H2O 0.18 g CoSO4 x 7 H2O 0.1 g CaCl2 x 2 H2O 0.18 g ZnSO4 x 7 H2O 0.01 g CuSO4 x 5 H2O 0.02 g AlK(SO4)2 x 12 H2O 0.01 g H3BO3 0.01 g Na2MoO4 x 2 H2O 0.03 g NiCl2 x 6 H2O 0.3 mg Na2SeO3 x 5 H2O 0.4 mg Na2WO4 x 2 H2O 1000 ml Distilled water 1. First dissolve nitrilotriacetic acid and adjust pH to 6.5 with KOH, then add minerals. Adjust final to pH 7.0 with KOH.