Inofficial medium: This medium was provided by external sources and is possibly not curated by experts.

Culture medium recipe

1 The culture medium consists of two layers to create opposing gradients of O2 and Fe(II). The top layer is the semisolid mineral salts medium and the bottom layer serves as the iron source.
Compound Amount Unit Conc. [g/L] Conc. [mM]
FeS solution 50 ml - -
Modified Wolfe's mineral solution 50 ml - -
Agarose 1 g 10 15.86
Equipment needed: Autoclave
Compound Amount Unit Conc. [g/L] Conc. [mM]
Modified Wolfe's mineral solution 100.000 ml - -
Trace minerals (see Medium No. 197 1.000 ml - -
MES 0.195 g 1.931 9.889
NaHCO3 0.042 g 0.416 4.95
Agarose 0.150 g 1.485 2.356
1 Adjust pH to 6.2.
2 Autoclave both layer solutions. Shortly after autoclaving, pipette the bottom layer into each culture vessel (typically 0.75 ml in 10 ml glass vials, use pipette tips that have been cut to enlarge the opening). The bottom layer is allowed to cool for at least 30 min to ensure its solidification. Cool the top layer to 35 - 40C, add 1 ml Trace vitamins (see Medium No. 197) and adjust pH to 6.1 - 6.4 by bubbling with sterile CO2 gas. Slowly overlay the top layer onto the solidified bottom layer (3.75 ml in the 10 ml vial). Allow to solidify the top layer a minimum of 3 hr to a maximum of overnight. To inoculate, 10 �l of the inoculum is drown into a pipette tip and inject just above the bottom layer. Seal vials with butyl rubber stoppers and replace the gas phase with a N2-CO2-O2 (8:1:1, v/v) gas mixture.
Solution occurs in 1 other media (first defined in Medium J628).
Compound Amount Unit Conc. [g/L] Conc. [mM]
FeSO4 x 7 H2O 46.2 g 154 553.927
Na2S x 9 H2O 39.6 g 132 549.583
Distilled water 300.0 ml - -
1 Prewarm distilled water at 50C in a beaker with a stir bar. While rapidly starring the water, add FeSO4 x 7H2O, followed immediately by Na2S x 9H2O. A thick black precipitate will form instantly. Stir continuously for 2 to 3 min. Remove the mixture to a narrow-mouthed glass bottle (500 ml) that can be tightly stopped. The bottle is filled to the top with distilled water and capped. Allow to settle for several hours, decant and replace the overlaying water. Repeat this procedure at least five times to wash the FeS precipitate. Check pH to be close to neutral. To stock the FeS solution, fill the bottle with distilled water and cap. Remove the overlaying water when prepare the bottom layer.
Solution occurs in 3 other media (first defined in Medium J628).
Compound Amount Unit Conc. [g/L] Conc. [mM]
NH4Cl 1.00 g 1 18.695
MgSO4 x 7 H2O 0.20 g 0.2 0.811
CaCl2 x 2 H2O 0.10 g 0.1 0.68
KH2PO4 0.05 g 0.05 0.367
Distilled water 1000.00 ml - -


Last modified: 22.02.22
Source: JCM
Taxonomic range:  Bacteria
Medium type: Defined medium
Final pH: 6.2
Equipment needed: Autoclave
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Associated strains

All strains for this medium: 3

Cultivation metadata from 3 strains BacDive

phyla 1 3 strains
oxygen microaerophile 1 strain
temperature mesophilic 3 strains