Can BL21 E.coli be induced by IPTG? - (Oct/22/2006 )
I am using Qiagen pQE31 plasmid to express my protein in E.coli strain BL21. pQE31 has the lac operon, but it does not contain the lac repressor coding region. So I need to use a E.coli strain which contains the lac repressor coding region in its genome. Will BL21 do this job? I tried once already, but found protein expression both in the "induced" and "non-induced"group. Anybody can give me some suggestion? Thanks a lot!!!
-sure-
QUOTE (sure @ Oct 22 2006, 08:43 PM)
I am using Qiagen pQE31 plasmid to express my protein in E.coli strain BL21. pQE31 has the lac operon, but it does not contain the lac repressor coding region. So I need to use a E.coli strain which contains the lac repressor coding region in its genome. Will BL21 do this job? I tried once already, but found protein expression both in the "induced" and "non-induced"group. Anybody can give me some suggestion? Thanks a lot!!!
which strain of BL21 are you using, BL21 or BL21(DE3)
you need a DE3 lysogen to be able to express(i think)
hope this helps
rich
-Jimmy_september-