[RASMB] Common contamination in recombinant protein preparation

[Carlos Ramos]

Dear Dror,
I first had this problem while working with apomyoglobin and have seen many
researchers with the same problem. Nucleic acids contaminate protein
purification, contribute to UV absorption and create artifacts in protein
concentration determination. It is one of the main causes of
misinterpretation of circular dichroism spectra.
Please see the references below for how a possible way to deal with the
problem:
Hope they help you.
Regards,
Carlos Ramos

-Ribeiro-Jr, E.A., Ramos, C.H.I. (2004). *Origin of the anomalous circular
dichroism spectra of many apomyoglobin mutants.* *Anal. Biochem*. *329*,
300-306.

-Correa, D.H.A., Ramos, C.H.I. (2009) The use of circular dichroism
spectroscopy to study protein folding, form and function. *African J.
Biochem. **Res.* 3, 164-173.

On Mon, May 31, 2010 at 3:51 AM, Dror Noy <dror.noy at weizmann.ac.il> wrote:

> Not exactly AUC related but there's a chance to find here a few people who
> work with proteins and do care about their UV absorption properties:
> We make a variety of native and artificial recombinant proteins and often
> encounter a situation where the apparently pure fraction according to
> SDS-PAGE gels has its UV absorption peak blue shifted from the expected ~280
> nm  toward 260 nm. This seems to be a general problem and usually happens
> when proteins are purified from inclusion bodies. We suspect DNA
> contamination but so far we were unable to get rid of it. I'd be very
> grateful for tips from people who experienced this phenomenon and were able
> to solve it.
> Thanks,
> Dror Noy
> _______________________________________________
> RASMB mailing list
> RASMB at rasmb.bbri.org
> http://rasmb.bbri.org/cgi-bin/mailman/listinfo/rasmb
>



-- 
Carlos Ramos
Instituto de Quimica UNICAMP
Sala: 19-3521-3144
Lab: 19-3521-3036
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://list.rasmb.org/pipermail/rasmb-rasmb.org/attachments/20100531/8a823514/attachment.htm>