Media Recipes

Contents
General Information
YEPD
YEPG
YEPD +G418
Complete Minimal
Dropout
Minimal
MSAC Pre-Sporulation
2% KAc Sporulation
CSM Formulation

In General:

If pouring plates, the volume of the flask containing the media should be at least 2X the volume of the media.  (i.e. autoclave 1 liter of media in a 2 liter flask.)

Autoclave 20-25min at 250°F on the liquid cycle.  Autoclave times may have to be increased if autoclaving many flasks simultaneously.

After autoclaving, swirl the flask to thoroughly mix agar, which tends to be concentrated at the bottom of the flask.

If solutions are added to the media after autoclaving, gently swirl to thoroughly mix the added solution (or a stir bar can be added before autoclaving).

Generally, 1 liter of media should make 35 to 40 100mm diameter plates.

If bubbles are present in the media after pouring the plates, remove the lids and briefly flame the plates to remove the bubbles.  This only removes the bubbles and does not improve sterility.

These recipes are for plates.  The recipes for liquid media are identical except agar is not added.

YEPD (aka YPD)
in 1 liter of H2O dissolve-
    20g dextrose
    20g bacto-peptone
    10g yeast extract
then add-
    20g bacto-agar (for plates)
autoclave

YEPG
in 1 liter of H2O dissolve-
    20g bacto-peptone
    10g yeast extract
then add-
    20g bacto-agar
autoclave

after autoclaving, add 50mls of a sterile 40% galactose solution.

YEPD + G418
in 1 liter of H2O dissolve-
    20g dextrose
    20g bacto-peptone
    10g yeast extract
then add-
    20g bacto-agar
autoclave

after autoclaving, add 400mg G418 (geneticin)
(we use 400mg/liter, however the Calbiochem product data sheet recommends 0.5 - 1g/liter for yeast)

Complete Minimal (aka Synthetic Complete)
in 1 liter of H20 dissolve-
    20g dextrose1
    6.7g yeast nitrogen base without amino acids
    0.79g CSM2 (Qbiogene)
then add-
    20g bacto-agar

Dropout Media
    20g dextrose1
    6.7g yeast nitrogen base without amino acids
    approximately 0.7g CSM2 minus a specific amino acid or nucleotide (for example CSM -URA).
    The exact amount of CSM dropout to add is on  the CMS dropout container.
then add-
    20g bacto-agar

Minimal (aka Synthetic Minimal)
in 1 liter of H20 dissolve-
    20g dextrose
    6.7g yeast nitrogen base without amino acids
then add-
    20g bacto-agar

MSAC Pre-Sporulation
in 1 liter of H20 dissolve-
    20g potassium acetate
    6.7g yeast nitrogen base without amino acids
    0.79g CSM
then add-
    20g bacto-agar

2% KAc Sporulation
in 1 liter of H20 dissolve-
    20g potassium acetate
    10mg/L of essential amino acids and nucleotides (i.e. if a strain is Ura- Leu- add 10mg each of Uracil and Leucine)
then add-
    20g bacto-agar

1Other sugars can be substituted for dextrose at the same concentration.  If using galactose add 50mls of sterile 40% galactose solution after autoclaving.

2CSM contains a mixture of amino acids and nucleotides at the following concentrations.

CSM Formulation - Qbiogene mg/liter
Adenine 10*
Arginine 50
Aspartic Acid 80
Histidine 20
Isoleucine 50
Leucine 100
Lysine 50
Methionine 20**
Phenylalanine 50
Threonine 100**
Tryptophan 50
Tyrosine 50
Uracil 20
Valine 140
Total 790
*Minimum quantity for healthy growth and yet optimized to promote red color in certain adenine auxotrophs

**80mg/liter of Homoserine is substituted for Threonine in mixtures where Methionine is dropped-out