Hi All, I've recently swapped over to expression in the ArcticExpress(DE3) cells for a particularly rock-like protein. I've got soluble expression but I'm having the issue of Cpn60 (the overexpressed chaperonin) piggybacking along with the tagged protein. Google-fu and the CCP4bb archives indicate that this is a known issue but I haven't seen a solution thus far. Does anyone out there have any tricks up their sleeve?
Also in case you were wondering in the various BL21 lines, even at extremely low temperatures and 10 uM IPTG, it expresses well but produces inclusion bodies that are completely insoluble in 8M urea, 6M guanidine, high temperature, high pH, high reducing agent, and a number of detergents so swapping back to another cell line isn't in the cards. Any help would be appreciated. Cheers, Katherine
