Kinase Assay Question

Wed Feb 22 13:02:19 EST 1995

James Smith writes:

>The Activity is measured in pmol ATP incorperated per minute.  I
>normalise this by dividing by the TOTAL protein concentration of the
>initial cell lysates (mg/ml) as determined by the BioRad assay
>system (OD taken @ 595nm etc).  Ideally, I would prefer to determine the
>protein concentrations of the individual 18% and 45% ammonium sulphate
>cuts but unfortunately the BioRad system doesn't work with ammonium sulphate.
>Does anyone know of any other protein concentration assay system that can
>work in the presence of ammonium sulphate? 

Try the BCA Protein Assay Reagent Kit from Pierce (1-800-874-3723
in the US or 31 1860 19277 in the Netherlands).  They say the
assay is compatible with 3.0% ammonium sulfate (but not with 20%).
If you are using 18% and 45%, this may not be helpful to you.
This protein assay also works in the presence of detergents.

Hope this is of some help.

jma at

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