I am trying to screen my transformant yeast which contain
YEp-based shuttle vector by URA-3 auxotroph test. OK, I have got the
positive clones but when I check their plasmids , I can't found them, by
glass bead extraction and transform back into the E.coli. Can anyone explain
to me why no have E.coli transformant when the auxotroph screen is give
me a positive result? And anyone can tell me where can I get the detail
of this case?
Thank you .