# 81: MINERAL MEDIUM FOR CHEMOLITHOTROPHIC GROWTH (H-3)


## Main sol. 81

50	ml	**Solution A**	
920	ml	**Solution B**	
20	ml	**Solution C**	
5	ml	**Standard vitamin solution**	

1. Solutions A, B, C are autoclaved separately for 15 min at 121°C, cooled down to 50°C and then mixed aseptically with 5.0 ml filter-sterilized standard vitamin solution (see below).The final pH of this medium should be 6.8 without adjustment.
2. For chemolithotrophic growth incubate the culture under an atmosphere of 2% (v/v) O2, 10% CO2, 60% H2 and 28% N2. For heterotrophic growth supplement the mineral medium with an appropriate carbon source (0.2% carbohydrate or 0.1% organic acid). For growth on nitrogen-free medium, omit NH4Cl and incubate the culture under an atmosphere of 2% (v/v) O2, 10% CO2, 10% H2 and 78% N2 or heterotrophically under 2% (v/v) O2 and 98% N2. For more details see Ref. 1515 and Ref. 3363.


## Solution A

2.3	g	KH2PO4	
2.9	g	Na2HPO4 x 2 H2O	
50	ml	Distilled water	


## Solution B

1	g	NH4Cl	
0.5	g	MgSO4 x 7 H2O	
0.01	g	CaCl2 x 2 H2O	
5	mg	MnCl2 x 4 H2O	
5	mg	NaVO3 x H2O	
5	ml	**Trace element solution SL-6**	
915	ml	Distilled water	
20	g	Agar, if required	


## Solution C

0.05	g	Ferric ammonium citrate	
20	ml	Distilled water	


## Standard vitamin solution

10	mg	Riboflavin	
50	mg	Thiamine-HCl x 2 H2O	
50	mg	Nicotinic acid	
50	mg	Pyridoxine hydrochloride	
50	mg	Calcium pantothenate	
0.1	mg	Biotin	
0.2	mg	Folic acid	
1	mg	Vitamin B12	
100	ml	Distilled water	


## Trace element solution SL-6

0.1	g	ZnSO4 x 7 H2O	
0.03	g	MnCl2 x 4 H2O	
0.3	g	H3BO3	
0.2	g	CoCl2 x 6 H2O	
0.01	g	CuCl2 x 2 H2O	
0.02	g	NiCl2 x 6 H2O	
0.03	g	Na2MoO4 x 2 H2O	
1000	ml	Distilled water