David Singleton wrote:
> I received strain Y190 from ATCC, and streaked it out to single colonies
> as per the instructions that came with the vial. After about 3 days of
> growth, I had appr. 90% white colonies and 10% red colonies (presumably
> due to the ade2 marker in this strain.) When I called to ask "what's up
> with two colony types?" I was told that the white colonies were probably
> ADE2 revertants. Has anyone worked with this strain (reporter for
> two-hybrid, deposited by S. Elledge), and is it really this unstable?
Yes. I am working witht the Y190 from S. Elledge.
Y190 should appear slightly pink or red (because of the ade2-101
and grow to >2 mm in diameter. However, small white colonies will form
at a rate of 1-2% due to spontaenous mutations that eliminate
mitochondrial function. Avoid these white colonies when inoculating
Sang-Chul Nam, Dept. of Biological Sciences, KAIST, Korea