|Reagent/Final Vol||400 ml||800 ml||1600 ml|
|Tryptone||8 g||16 g||32 g|
|Yeast||2 g||4 g||8 g|
|NaCl||0.2 g||0.4 g||0.8 g|
|0.25 M KCl (add after dissolving the foregoing)||4 ml||8 ml||16 ml|
pH 7.0 with 5 N NaOH. Autoclave. Add 2 mls filter sterilized 2M MgCl2 to each 400 ml.