M9 Medium – Agar (1L)

• Make 500 mLs of M9 Medium (2X):

• Begin with approx. 400 mLs MilliQ H₂O
• Weigh out and add ingredients with constant stirring:

• KH₂PO₄ 3g
• Na₂HPO₄ 6g
• NaCl 0.5g
• NH₄Cl 1g

• Make 500 mLs of 3% Bacto-Agar:

• Begin with approx. 400 mLs MilliQ H₂O
• Weigh out and add :

• Bacto-Agar 15g

• Autoclave the M9 Medium and Bacto-Agar separately
• Allow to cool in 50˚ water bath
• Add the following to the M9 Medium

• 1M MgSO₄ 1mL
• 0.01M CaCl₂ 10mL

• Mix the equal volumes of M9 Medium and 3% Bacto-Agar
• Add sugars and supplements as required (e.g. 0.2% glucose).

Verified 6/1/2005 by MaryAnn Hartman; Botstein, D., R.W. Davis, J.R. Roth. Advanced Bacterial Genetics, Cold Spring Harbor, 1980.