Yeast 3-hybrid problem

[Bernhard Mayr]

Yes I streaked untransformed CG1945 and Y190 on -His and -Trp and -Leu
plates: No growth on -Leu or -Trp, on -His w/o 3-AT (as expected) both
strains grow, but when I add 3-AT in the concentration recommended, 
they
stop growing.

> I feel obliged to ask the obvious question - does your host strain
> grow on -His media without transformation with a plasmid?
> (ie. has your yeast stock become contaminated with a HIS strain?)

I did that: I transform both strains with empty (= no insert) bait and
prey vector and they start growing.

> Try a test transformation using a HIS
> plasmid and streak the untransformed and the transformed cells on
> +/- His media.

Just another question: Can high humidity in the incubator have an
effect?

-- 
Bernhard Mayr
The Salk Institute
Peptide Biology Labs
10010 North Torrey Pine Road
La Jolla, CA 92037
USA

Fon +1 858 453 4100 ext 1176
Bernhard