Medium 155: DOUBLE LAYER AGAR FOR PHAGE PROPAGATION

First layer:
  Nutrient agar                      28 g
  Yeast extract powder                3 g
  Peptone                             5 g  
  Distilled water                  1000 ml
	
Adjust pH to 7.4 +/- 0.2.
Sterilized at 121°C for 15 min.

Second layer (per 1 plate):
  0.7% meat peptone agar (45°C)       2.5 ml 
  bacterial culture*                  0.1 ml
  phage suspenzion                    0.1 ml

*Add sterile solution of CaCl2 (stock solution 
0.02M) to final concentration 0.002M.

  0.7% meat peptone agar:
   Nutrient broth                      13 g
   Yeast extract powder                 3 g
   Peptone                              5 g
   Agar no. 1                           7 g  
   Distilled water                   1000 ml	

Adjust pH to 7.4 +/- 0.2.
Sterilized at 121°C for 15 min.