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