Yeast Selective Media and Agar

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  • Minimal SD Base (Clontech 630411)
  • Dropout Supplement (as an example -Leu DO supplement has all the nutrients except leucine)
  • Bacto Agar (if making plates)

Selective yeast media is made so that a particular amino acid or nutrient (typically Leu, Trp, Ura, His or Ade) is missing and must be provided by the yeast strain. Therefore a yeast strain which is auxotrophic for that nutrient can only grow on that selective media if a selective plasmid is provided. See [Wikipedia Article on Auxotrophy]. As an example, BY4742 is auxotrophic for Leu, Lys, His and Ura. Therefore this strain cannot grow on -Leu plates, unless transformed with a plasmid containing the LEU2 gene. In this way transformants can be selected.


  • Weigh out 2.67g/100 mL of Minimal SD Base and 0.069g/100mL of the appropriate dropout supplement.
  • If making plates, add 2g/100mL of bacto-agar
  • Stir to dissolve and check that pH is at 5.8
  • Autoclave for 20 min at 121C using the liquid cycle
  • Unless adding adenine hemisulfate, there is no need to let the media cool, so plates can be poured immediately.
  • Pour plates, let dry and store in the cold room