Hi Weijun, you can get a kit from Takara (chaperone kit #3340) which has five different chaperone plasmids (combinations of various chaperone). It worked for me assofar that I could express huge amounts of the chaperones, but my target protein was either not expressed at all any more (seems as if E. coli was all busy expressing chaperons) or still insoluble ;-( And unfortunately the structures of the chaperones were all solved already ;-)
If disulfides might be the problem - try expression into the periplasma (some pET vectors encode leader sequences for that). Otherwise try other expression systems (baculovirus, mammalian....) All the best, Petra > Dear All, > > I got enclusion body in many cases when I tried to express human > proteins in E coli. I would like some suggestions on how to go about > it. I would also like to try co-expression of GroEL/GroES or > DnaJ/DnaK, and would like to know where to get the plasmids. > > Any help or comments would be appreciated. > Weijun > -- Petra Verdino, PhD Research Associate The Scripps Research Institute, BCC206 10550 North Torrey Pines Road CA 92037 La Jolla, USA tel:1-858-784-2294 fax:1-858-784-2980
