# 1369: ECTOTHIORHODOSPIRA MAGNA MEDIUM ## Main sol. 1369 0.5 g KH2PO4 30 g NaCl 0.5 g NH4Cl 0.2 g MgCl2 x 6 H2O 1 g Na-acetate 0.5 g Na2S2O3 0.5 g Na2S x 9 H2O 5 g NaHCO3 5 g Na2CO3 0.1 g Yeast extract 10 µg Vitamin B12 1 ml **Trace elements solution (Pfennig & Lippert,1966)** 1000 ml Distilled water 1. pH 9.0-9.5 2. Prepare the medium without the NaHCO3, Na2S x 9 H2O, Na2CO3 and vitamin B12, under a nitrogen atmosphere. 3. Autoclave and add the vitamin B12 from a filter-sterilised stock solution and the NaHCO3 (autoclaved in sealed, half full vessels), Na2S x 9 H2O, Na2CO3 from sterile stock solutions. The final pH of the medium should be 9.0-9.5. ## Trace elements solution (Pfennig & Lippert,1966) 5 g EDTA 2.2 g FeSO4 x 7 H2O 0.1 g ZnSO4 x 7 H2O 0.03 g MnCl2 x 4 H2O 0.03 g H3BO3 0.2 g CoCl2 x 6 H2O 0.03 g CuCl2 x 2 H2O 0.03 g NiCl2 x 6 H2O 0.03 g Na2MoO4 x 2 H2O 1000 ml Distilled water 1. pH 3.0-4.0