Freimoser:Recipes:Yeast:SC Sfree

Remark:

This recipe describes the mixing of a sulfur free SC-medium. All sulfur sources in “normal” SC-medium are replaced by other salts, mostly chlorides. The changes are also indicated. The phosphate source is separate in order to allow mixing of media with different phosphate content. The 20x salt solution, 100x phosphate source and 40% glucose solution were autoclaved. All other solutions were filter sterilized. The described procedure works, but it is possible that there are simpler solutions. But it is not possible to make a stock solution of all trace elements for example.

20x Salt solution, 500 ml

MgCl₂: 16 g (4 mM) NaCl: 1 g (1.7 mM) CaCl₂ x 2 H₂O: 1 g (1 mM)

100 x phosphate source, 100 ml

KH2PO4: 10 g (7.5 mM)

1000x trace element solution 1, 10 ml

Boric acid (H₃BO₃): 0.05 g (8 uM) CuCl₂ x 2 H₂O: 0.004 g (0.25 uM) (replaces CuSO₄) KI (potassium iodide): 0.01 g (0.6 uM) C₄H₁₀O₆Zn (zinc acetate): 0.055 g (2 uM) (replaces ZnSO₄)

Separate solutions:

=MnCl₂ x 4 H₂O (manganese chloride):= 0.04 g in 10 ml (1000x) (2 uM) (replaces MnSO₄)

=Na₂MoO₄ (sodium molybdate):= 0.02 g in 10 ml (1000x) (1 uM)

=FeCl₃ x 6 H₂O (ferric chloride):= 0.02 g in 10 ml (500x) (1.5 uM)

NH₄Cl (ammonium chloride): 2 g in 10 ml (100x, 37.8 mM final conc. In medium)

Additional components:

=Glucose (C₆H₁₂O₆):= 40% (20x)

=MES buffer (2-(N-morpholino)ethanesulfonic acid):= 0.5 M, pH 6 (10x)

YNB 1000x vitamin solution