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Suitable bacterial reporter vectors - (Aug/11/2009 )

Dear all,

This may be more of a molecular biology question...

I want to use a reporter plasmid to look for activation of a particular gene promoter in E. coli. I plan to clone the promoter sequence for the GOI into a plasmid upstream of a reporter gene (either GFP or beta-gal i havent decided yet).

Please could anyone recommend suitable plasmids for doing this. pUC18 for example could be suitable for a beta-gal reporter but Im not sure of a suitable GFP containing vector that i could use.

What will be the impact of plasmid copy number? - i assume that high copy number would give me a stronger signal upon activation of the promoter?

All the best,



Please see the following attachment.

Hope this helps
Attached File


many thanks!


I think using the pGFPmut3.1 promoter should be suitable ...delete the lac promoter and replace it with your promoter of choice!

If you are going to screen for promoter-activity on agar-plates the higher the copy number the better because you will be able to find high-level expression clones by eye (even without UVlight).