AT Minimal Medium

Reference: Tempe, 1977, PNAS 74:2848

AT is prepared as 20X buffer and 20X salts solutions that are supplemented with a carbon source.

20X AT Buffer	g/mol	g/L	Final Concentration (1X)
KH₂PO₄	136.1	214	0.079 M
pH to 7.0 w/ NaOH		35 (solids)	0.044 M

20X AT Salts	g/mol	g/L	Final Concentration (1X)
(NH₄)₂SO₄	132.14	40	0.015 M
MgSO₄-7H₂O (anhydrous,1.6)	246.5	3.2	0.6 mM
CaCl₂-2H₂O (anhydrous, 0.151)	147.0	0.2	0.06 mM
FeSO₄-7H₂O	278.0	0.1	0.027 mM
MnSO₄-H₂O	169	0.024	0.0071 mM

1X AT Medium	g/L	Final Concentration (1X)
20X buffer	50mL/L	1X
20X salts	50mL/L	1X
50% glucose or 40% succinate	10mL/L	0.5%
+/- Bacto-agar	15	1.5%

Prepare sterile, autoclaved stocks of 20X salts, 20X buffer and the carbon source. Add the appropriate amounts to either sterile deionized water (AT broth) or molten (55 ^oC) sterile 1.5% agar-water (AT agar); mix gently, but thoroughly.
Iron will precipitate after autoclaving salts to form red iron oxides. (i.e., rust)
After 1X broth made, there is no need to autoclave. So the process of 1X preparation should be sterile. DI should be autoclaved separately.
The sugar (e.g., 50% glucose, 40% succinate) needs to be filtered before storage.