I have tried hard to construct a strain in which a gene of my interest
is under the control of a Gal promotor. I know the gene is essential,
it is toxic when the expression is high. The strategy that I used is
to replace the chromosomal allele by an in vitro constructed 5'UTR-Gal
ORF. Unfortunately, this is not very helpful because that integration
seems to occur somewhere else or the basal expression is high enough
to allow the growth. Although I have used a varieties of combination
of galactose/glucose, galactose/raffinose, colonies grown on these
medium can also grow on glucose containing media.
So I would like to know whether someone in this group has ever encountered
this kind of problem. I would like to hear your suggestions, too.
Institute of Pathology
Case Western Reserve University
2085 Adelbert Rd.
Cleveland, OH 44106
Fax: (216) 368-5484
Phone: (216) 368-5183
e-Mail: SXL29 at PO.CWRU.EDU