# 1583: MEDIUM FOR AMMONIA OXIDIZING BACTERIA (STRAINS FROM SOIL)


## Main sol. 1583

535	mg	NH4Cl	
54	mg	KH2PO4	
74	mg	KCl	
49	mg	MgSO4 x 7 H2O	
147	mg	CaCl2 x 2 H2O	
584	mg	NaCl	
1	ml	**Trace element solution**	
2	ml	**Cresol red solution 0.5 g/L**	
1000	ml	Distilled water	

1. Autoclave, subsequently adjust pH of the medium to about 7.8 by addition of sterile 10% NaHCO3 (medium is turning from yellow to pink).
2. Important: During growth, add NaHCO3 to readjust pH as soon as pH indicator changes to yellow. For stock cultures, 5 g l-1 CaCO3 (will stay as a precipitate) or 4.8 g l-1 HEPES may be added to keep pH neutral for a longer time.
3. Aeration must be adjusted according to the density and activity of the culture. At low cell concentrations (which is the case most of the time) cells are sensitive to strong aeration (don't shake the cultures).


## Trace element solution

975	ml	Distilled water	
25	ml	HCl, 1M	
45	mg	MnSO4 x 4 H2O	
49	mg	H3BO3	
43	mg	ZnSO4 x 7 H2O	
37	mg	(NH4)6Mo7O24 x 4 H2O	
973	mg	FeSO4 x 7 H2O	
25	mg	CuSO4 x 5 H2O	


## Cresol red solution 0.5 g/L

50	mg	Cresol red	
100	ml	Distilled water