I've got a problem:
after around two weeks of fusion protein expression (protein-Cterminus-Thrombin_tag-EGFP-6xHis_tag) I see 2 bands on a gel (instead of one band). These bands correspond to the protein and GFP tag (last one is fluorescent on the gel).
In my elution buffer I have protease inhibitor, 1M imidazole, 50 mM TRIS-HCl(pH 7.6), and 500 mM NaCl.
Why does it happens?
Sorry if it's already has been discussed before, but I didn't find it yet.
Thank you for your suggestions,
Edited by 6xHis_tag, 04 September 2012 - 06:50 AM.