Some work i've been doing has faced a problem of distinguishing between SD and
YEPD. In my case, addition of amino acids to SD did not help - so it may not be
the same as your mutants. some of the differences between SC/SD and YEPD that i
have come across are :
1. Ion concentrations - SD has higher Ca+2 and Mg+2 but lower K+ levels than
2. Nutrients(?) - many nutrients (eg. some fatty acids) are present in YEPD but
have to be added to SD.
3. pH - i find a consistent difference in the pH between SD and YEPD.
Specifically, with respect to your question, i was wondering if the mutant in
the secretory pathway (?) was extra sensitive to some ion levels - you could try
adding salts back to YEPD to see if your mutants fail to grow on salt-
supplemented YEPD. pH could be tested similarly.
As to the nutrients - i guess they are just too complex to dissect this way. But
initially, just spiking your SD with some YEPD might indicate if something in SD
was toxic to the mutants or if SD was missing some nutrient.
Hope this was helpful
Subject: Mutants that fail to grow on SD but are not defective in a.a
From: roberg at athena.mit.edu at Internet
Date: 10/1/95 12:14 PM
I have made a knockout in a gene that plays a role in the secretory pathway.
rich media the k.o. strain is viable but it is unable to grow on minimal media
(SD). It appears the additional stress of having to synthesize amino acids is
to much for this mutant. I would like to hear from anyone who has had a
experience or who has any insight about differences in yeast physiology due to
growth on SD vs. YPD/SC.