Hi
I know if DNA is free in mixture with proteins it could be percipitated with
Streptomycin sulfate. I have to look for the concentration.
Mahmood
Dalhousie university
Bernard P. Murray, PhD wrote:
> In article <368A090F.767347C0 at uni-molgen.gwdg.de>, Silke Beismann
> <sbeisma at uni-molgen.gwdg.de> wrote:
>> > Hi,
> > I am trying to purify a protein from the amino acid biosynthetic
> > pathway. It should not have anything to do with DNA but it seems that it
> > binds to it. I tried digestion of the crude extract with DNase I and
> > RNase A, precipitation with ammonium sulfate or polyehtylene imine,
> > hydroxyapatite chromatography- but the spectrum still looks like an
> > nucleic acid spectrum. Does anyone know an efficient method to remove
> > the
> > contaminating nucleic acids?
> > Thanks in advance,
> > Silke
>> Just curious. I don't know how the "spectrum" can pick out
> the DNA nature of the protein/complex but is there any way
> that your protein could be modified (eg. ADP-ribosylated
> or a prosthetic group) that would give the impression of
> DNA contamination? Maybe treatment with a DNA kinase
> would help determine if it is really adsorbed DNA
> (should only label if it is really "DNA").
> Bernard
> --
> Bernard P. Murray, PhD
> Dept. Cell. Mol. Pharmacol., UCSF, San Francisco, USA