In article <1994Jul27.213302.1 at aurora.alaska.edu>, fsajb3 at aurora.alaska.edu
> Anyone have experience with this problem?
> Our lab has been transforming XL1-blue chem comp cells (made competent
> in our lab using FSB protocol) with various pBSIIKS constructs. There has
> been no problem getting transformants, but the colonies grow extremely slow,
> and there is a really long delay before any blue color develops for blue/white
> selection. I checked to make sure we weren't overdosing the plates with
> ampicillin, everthing seemed normal. We are using bluo-gal and 100mM IPTG for
> color selection. Any information is greatly appreciated.
i've had the same problem, but was assured by others in the lab that it's
just a quality of the cells. they always grow slowly. i've encountered
similarly slow growing strains with invitrogen's INVaF' cells. i also
think that color selection in general takes a bit longer than the actual
cell growth does. i usally leave plates @ 37 degrees for 24-36 hrs, then
leave them at room temp for another 12-24. the time at room temp slows
down cell growth but allows for pretty good color development.
you aren't doing anything wrong...it's just the way they work.
as a marginally humorous aside, i just noticed that you're posting from
alaska. i don't know what you consider room temp up there (maybe 5-10 C),
but down here in the heartland it's 24. :)
NOT BIG PANTS!!!
eric c. anderson
anderson at pharmdec.wustl.edu
660 s. euclid box 8103
washington univ. school of medicine
dept of molecular biol. and pharmacology
st. loser, misery 63110