Yeast Growth Media
Selecting the Right One
There are a wide variety of yeast media formulations available. The choice should be made based on the type and strain of yeast, the type of desired growth, and of course the details of the work being done. Agar can be added to media for a solid growth substrate.
Yeast Nitrogen Base (YNB) formulations are a blend of YNB and a carbon source such as dextrose, galactose, or raffinose. To make the desired synthetic defined medium, ammonium sulfate and selected amino acids and nucleosides are added. These are often called drop-out media because depending on the auxotroph being studied, one or more components is "dropped out". These media are useful for confirming a strain's phenotype, selecting yeast transformants, and culturing the organism.
YPD medium is composed of peptone, dextrose, and yeast extract. As it is an undefined, complete medium, it is not suitable for studying auxotrophs but can be used for growing most Saccharomyces cerevisiae strains. YPDA is the same formulation as YPD, but supplemented with adenine hemisulfate supplement. The adenine is added to provide faster growth, higher saturation densities, and the absence of red/pink color in ade1 and ade2 mutants. YEP medium is YPD without the dextrose, so the carbon source can be chosen by the user.
Schizosaccharomyces pombe prefers slightly different conditions. YE Medium is made with yeast extract and dextrose. This medium inhibits sporulation and conjugation in S. pombe. YES is YE with amino acid and nucleoside supplements, for a complete S. pombe growth medium.
Edinburgh Minimal Medium is an S. pombe medium containing glucose, salts, vitamins, and minerals, also used for vegetative growth. With low glucose, it is used for yeast transformations. With minimal glutamate it is used for sporulating diploids.
Drop out media
Yeast Nitrogen Base (with or without AS, amino acids, other amendments)- Table 1
Drop out base (yeast nitrogen base + ammonium sulfate + carbohydrate)- Table 2
Drop out mix complete (without YNB, with all amino acids, with or without other amendments)- Table 3
Custom drop out mix (without YNB, without one or more amino acids or nucleosides of your choice)- Table 4