Medium data

Search for medium no. = [915].
Unless otherwise stated, sterilize media by autoclaving at 121°C for 15 min.

915   SEMI-SOLID AUTOTROPHIC GROWTH MEDIUM FOR MAGNETOCOCCUS MARINUS

NaCl  16.4     g
MgCl2·6H2O  3.49    g
Na2SO4  2.74    g
KCl  0.47    g
CaCl2·2H2O  0.39    g
NH4Cl  0.3     g
Modified Wolfe's mineral solution (see below)  5.0     ml
Resazurin  0.4     mg
Distilled water  1.0     L
Agarose  2.0     g
Adjust pH to 7.2.
Mix components thoroughly, except agar, and adjust pH to 7.0. Add agarose to the medium and autoclave under a N2 gas atmosphere. After cooling to 50C, add the following solutions to the medium aseptically and anaerobically (autoclaved or *filter-sterilized):
0.5 M Potassium phosphate buffer (pH 7.0)  1.8     ml
40% Na2S2O3·5H2O solution  3.0     ml
Vitamin solution* (see below)  0.5     ml
5% L-Cysteine·HCl·H2O solution  4.0     ml
8% NaHCO3 solution*  2.35    ml
Keep the medium temperature at 50C until the medium is distributed into sterile screw-capped test tubes as described below.
Adjust pH to 7.0 - 7.2 with sterile HCl or NaOH solution. Then, aseptically and anaerobically, add the following solution (autoclaved):
0.01 M FeSO4·5H2Osolution (in 0.02 N HCl)  2.5     ml
Dispense the medium to sterile screw-capped test tubes (typically 12 ml medium into 125 by 15 mm test tubes) under air and cap. Allow to stand until the medium is solidified and a O2-gradient formed (as evidenced by a pink upper oxic zone and a colorless lower anoxic zone). Inoculate cells just below the pink-colorless interface in the medium tube using a syringe.
Modified Wolfe's mineral solution:
Use trace minerals (see Medium No. 151) with final 0.4 g/L Na2MoO4·2H2O, 0.02 g/L CuSO4·5H2O and 0.01 g/L NiCl2·6H2O.
Vitamin solution:
Thiamine·HCl  90.0     mg
myo-Inositol  40.0     mg
Calcium pantothenate  4.0     mg
p-Aminobenzoic acid  5.0     mg
Vitamin B12  5.0     mg
Pyridoxine·HCl  4.0     mg
Nicotinic acid  4.0     mg
Biotin  0.1     mg
Folic acid  2.0     mg
Distilled water  100.0     ml
Comment: The medium tubes can be stocked under a N2 gas atmosphere. In this case, prior to use, fill the head space with air and allow to stand until the O2 gradient is formed.