IPTG concentration for induction?

[Nathan Siemers]

Using the (powerful) T7/lac promoter system (novagen vectors) for
driving expression of recombinant proteins in coli, I have found that
induction even at 100 micromolar IPTG is often toxic.  As other people
have mentioned, titrate down in small scale trials.  The clearest way
to determine toxicity due to induction that I have found is to induce
at innoculation of the culture, then follow the growth profile over
6-12 hours.

nathan


-- 
Nathan O. Siemers  Bristol-Myers Squibb Pharmaceutical Research Institute
3005 First Avenue, Seattle, WA 98121  (206) 727-3741   siemers at bms.com