Hi All,
I also have a similar observation for proteins purified by Ni-NTA column. After
concentrating the sample eluted from the Ni-NTA column, I see a
brownish-yellowish tinge closer to the bottom of the filter with colorless
buffer on top. This is observed even for non-metal binding and non-FeS cluster
proteins and also for proteins after removal of the His-Tag. This is presumably
arising due to difference in viscosity where the protein gets concentrated
closer to the bottom of the filter.
Cheers,
Shiva
--- On Fri, 9/24/10, sandeep <toskgu...@rediffmail.com> wrote:
From: sandeep <toskgu...@rediffmail.com>
Subject: [ccp4bb] protein turns brown
To: CCP4BB@JISCMAIL.AC.UK
Date: Friday, September 24, 2010, 4:34 AM
Dear all,
I have purified protein from E.coli. expression system. the protein has been
purified with three independant columns. Now during concentration step using
amicon, the protein shows brown colour. what could be the reason.
best regards and Thanks,
sandy
