# 829b: THERMODESULFOBACTERIUM HYDROGENIPHILUM MEDIUM ## Main sol. 829b 30 g Sea Salt (SIGMA) 1 g NH4Cl 0.35 g KH2PO4 1.95 g MES [2-(N-morpholino) ethane sulfonic acid] 1 ml **Trace element solution SL-10** 1 ml **Selenite-tungstate solution** 0.5 ml Sodium resazurin (0.1% w/v) 0.5 g Na2CO3 0.5 g Yeast extract 1 ml **Seven vitamins solution** 1 ml **Growth-stimulating factors** 1 ml **Na-dithionite solution (5% w/v)** 1000 ml Distilled water 1. Dissolve ingredients (except carbonate, yeast extract, vitamins, growth-stimulating factors and Na-dithionite), boil medium for 1 min, then cool to room temperature under 80% H2 and 20% CO2 gas atmosphere. Adjust pH to 6.0 and dispense medium under same gas atmosphere into anoxic Hungate-type tubes or serum vials to 30% of their volume and autoclave. Add yeast extract, vitamins, and growth-stimulating factors from sterile anoxic stock solutions prepared under 100% N2 gas atmosphere and carbonate and Na-dithionite from sterile anoxic stock solution prepared under 80% N2 and 20% CO2 gas mixture. Vitamins and Na-dithionite are sterilized by filtration. Adjust pH of the complete medium to 6.5, if necessary. 2. After inoculation use 2 bar overpressure of sterile 80% H2 and 20% CO2 gas mixture. ## Trace element solution SL-10 10 ml HCl (25%) 1.5 g FeCl2 x 4 H2O 70 mg ZnCl2 100 mg MnCl2 x 4 H2O 6 mg H3BO3 190 mg CoCl2 x 6 H2O 2 mg CuCl2 x 2 H2O 24 mg NiCl2 x 6 H2O 36 mg Na2MoO4 x 2 H2O 990 ml Distilled water 1. First dissolve FeCl2 in the HCl, then dilute in water, add and dissolve the other salts. Finally make up to 1000.00 ml. ## Selenite-tungstate solution 0.5 g NaOH 3 mg Na2SeO3 x 5 H2O 4 mg Na2WO4 x 2 H2O 1000 ml Distilled water ## Seven vitamins solution 100 mg Vitamin B12 80 mg p-Aminobenzoic acid 20 mg D-(+)-biotin 200 mg Nicotinic acid 100 mg Calcium pantothenate 300 mg Pyridoxine hydrochloride 200 mg Thiamine-HCl x 2 H2O 1000 ml Distilled water ## Growth-stimulating factors 5 g Isobutyric acid 5 g Valeric acid 5 g 2-Methylbutyric acid 5 g 3-Methylbutyric acid 2 g Caproic acid 6 g Succinic acid 1000 ml Distilled water 1. Dissolve ingredients, adjust pH to 9.0 with NaOH, then autoclave under 100% N2 gas. ## Na-dithionite solution (5% w/v) 50 g NaHCO3 50 g Na2S2O4 1000 ml Distilled water 1. Dissolve NaHCO3 in water and make the solution anoxic by sparging with 80% N2 and 20% CO2 gas mixture. Then dissolve the Na-dithionite and filter sterilize the solution into anoxic Hungate tubes. Store the prepared solution in the dark and refrigerated. Prepare only small amounts of stock solution, as Na-dithionite decomposes rapidly.