Toxic genes

[Tim Angelotti]

If this repeats itself, I apologize, but my mail got a little 
funky on me.  I am trying to clone a cDNA in Bluescript and I found that 
all of my clones with the right orientation were very poor in growing and 
that the others all grew well.  Now I take this to mean that it is a 
toxic gene (an extracellular protein with a single TM domain).  Now, why 
does this occur?  Is it because the protein is being produced somehow or 
is it because a cryptic bacterial promoter is being used that is encoding 
a toxic gene product?  Any opinions outh there?  And next, what to do 
about it.  Do I try to use ABLE or TOPP cells from Stratagene that limit 
plasmid levels and hence toxicity?  And last, do I assume that any 
positive clones I receive are screwed up, rearranged?

Tim Angelotti
TU Muenchen
Institute for Pharmacology