Dear Matt,
Based on the follow-up information that you posted, I would be willing to
bet that the color you observe is caused by various Ni complexes formed with
DTT/BME/etc. Dialysis won't necessarily remove these complexes (especially
if protein is part of the complex) and EDTA may not destroy t
Hello Matt,
did you use a nickel (or similar) affinity column in the purification + is
there any beta-mercaptoethanol or DTT in your sample? Nickel can easily
'bleed' off the column and will turn brown when complexed with bME or DTT -
this complex can get quite large and even insoluble if enough
Hi Matt,
I sometimes see a similar thing with my proteins, which definitely don't
possess metal co-factors or prosthetic groups. I found that gel filtration
got rid of it - the browny-yellow stuff came out in the void fraction so I
figured it was aggregated protein. I think it was aggregation via t
you can do a simple wavelength scan at the synchrotron of the protein solution
frozen in a loop.
Best wishes
Kornelius
On Fri, 5 Sep 2008 12:21:29 -0400
Matthew Alan Bratkowski <[EMAIL PROTECTED]> wrote:
> Hello.
>
> I am working with a protein that turns a yellowish-brown color when it is
>
Matthew Alan Bratkowski wrote:
Hello.
I am working with a protein that turns a yellowish-brown color when it is
concentrated to around 2 mg/ml or higher in a small volume (a few hundred
uL). I was wondering if the protein bound a metal or other prosthetic
group that would give it this color? T
>
> I am working with a protein that turns a yellowish-brown color when it is
> concentrated to around 2 mg/ml or higher in a small volume (a few hundred
> uL). I was wondering if the protein bound a metal or other prosthetic
> group that would give it this color? The protein's color somewhat
> r
Hi Matt,
to check, if the color comes from a metal ion, you can get an AAS
analysis done. You need something in the range of 1 mg of well dialyzed
protein (metal free buffer!). We got an analysis done for the most
important metals (Mn, Fe, Co, Ni, Cu, Zn) for ca. 20 Eur per element
from a loca
