MEDIA FOR ANAEROBIC GROWTH 509 



Solution II 50 ml of 1 M Tris, pH 7.5 



Solution III 1 g K2HPO4 in 50 ml water. 



Solution IV 0,2 g Na2S • 9 H2O in 50 



ml water. 



Solution V 5.5 g of organic carbon 



source (neutralized; e.g., 

 malate) in 50 ml water. 



Autoclave the five solutions separately. Cool and mix in the order 

 indicated. Final pH 7.5, adjusted with cone. HCl. 



GREEN BACTERIA 



Chlorobium thiosidfatophiliim and C. limicola. 



After Larsen, "On the microbiology and biochemistry of the photo- 

 synthetic green sulfur bacteria." Kgl. Norske Videnskab. Selskabs 

 Skrifter, 1953, 1-205. 



Stock cultures: stabs in a medium containing 0.1% NH4CI, 0.1% 

 KH2PO4, 0.05% MgCl2, to 3% NaCl and 2% agar in tap water. The 

 medium is sterilized and allowed to cool to about 45 °C, Separately 

 sterilized solutions of NaHCOs, Na2S, and FeCls are then added asep- 

 tically to give the following final concentrations: 0,2% NaHCOs, 0,1% 

 Na2S • 9 H2O, and 50 /ig % Fe. The pH is adjusted to 7.3 by adding a 

 few drops of a sterile dilute solution of H3PO4. 



Synthetic Liquid Medium 



NH4CI 1.0 g 



KH2PO4 1.0 g 



MgCl2 0.5 g 



NaCl 10.0 g 



NaHC03 2.0 g 



Na2S203 or Na2S • 9 H2O 1.0 g 

 (C. thiosulfatophilnm can use either Na2S or 

 Na2S203 as electron donors, whereas C. limicola 

 utilizes Na2S but not thiosulfate.) 



Na2S • 9 H2O (if Na2S203 is used) 0.1 g 



CaCl2 0,1 g 



Fe (as FeCl3 • 6 H2O) 500.0 fig 



B (as H3BO3) 100.0 ^g 



Zn (as ZnS04 • 7 H2O) 100.0 jUg 



Co (as Co(N03)2 ' 6 H2O) 50.0 /ug 



Cu (as CUSO4 • 5 H2O) 5.0 jug 



Mn (as MnCl2 • 4 H2O) 5.0 /^g 

 Pyrex glass-distilled water to 1000 ml. 

 The pH is adjusted to 7,0-7.5 with H3PO4. 

 Incubation temperature: about 30°C, 



