Inclusion body purification - (May/17/2011 )

Hi

I have expressed a protein ( approx 16 KDa ) in E.coli. I use 0.5 mM IPTG for induction and growth conditions are 37 C . It results in over expression and production of inclusion bodies. I tried using Chloramphenicol after overnight induction with 0.2 mM IPTG and growth at 25 C. Chloramphenicol was supposed to shift the equilibrium of the formation of inclusion bodies towards dissociation. But it did not work.

Can anyone provide me with a good protocol for inclusion body purification? The protein I isolate has 9 cystiene residues and has a his tag.

Thanks
Sandy

you can denature and solubilize the protein with a buffer containing 8M urea. then you can purify your his-tagged protein on ni or co resin (in urea buffer), if you want.

then renature (refold) your protein by dialysis against buffer without urea (use small steps to enhance recovery).

by the way, you can try inducing with less iptg (0.1mM or less) and 16C.