In article <deusebe-0910961556130001 at cherubin.ens.fr>,
deusebe at wotan.ens.fr (Danièle EUSEBE) wrote:
> I have to induce beta-galactosidase in a liquid culture of E.coli Y1089
> lysogen for a lambda gt11 phage containing a beta-galactosidase-fusion
> protein gene.
> I have read in a protocole to use 10 mM IPTG, which seems to me an
> enormous amount, since I have to make a liter scale culture.
> Is this concentration required? What is the minimal efficient
> concentration to fully induce beta-galactosidase synthesis?
> Daniele EUSEBE(Ecole Normale Supérieure-INSERM U293-Paris-France)
> e-mail:deusebe at wotan.ens.fr
For expression of recombinant proteins off a plasmid, I try a range from
35-1000 uM to try to optimize expression; usually I don't need more than
100 uM and get very good expression at 35 uM. 10 mM does seem excessively