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Expression of protein in non target strain but unfortunately no protein expressi - (Dec/30/2008 )

Hi everybody,
Actually I have problem in my experiment I have to do CoTransformation into either TOP10 or DH10B ( because my first plasmid should to express to Arabinose operon and second one for lac operon so according for AraC promoter should just works I think in either TOP10 or DH10B .
But unfortunately my plasmid that expresses for lac operon called PKK223 3 Didn’t significantly express neither in DH10B nor TOP10 (Target strains in my experiment strategy) but I got significant expression in BL21 (DE3). My problem is : I cannot use cotransformation in BL21(DE3) because it will conflicts with Arabinose expression gene .
Please any Idea to help me because really iam in a trouble!



I am not sure if this would help but I remember using a strain by takara wherein i used their chaperone competent cells. The chaperones were induces by arabinose and tetracycline and my transformed gene by IPTG. I don't remember what strain was it but it surely worked in terms of expression, just that my protein still went into the pellet sad.gif.

If u don't find it, write back, I will hunt down teh details for you after i get back to the lab.

All the best


-T C-