Protein precipitation - acetone?

[Irit Rappley]

Some people add 1 mg/mL BSA to their sample in order to get the total  
protein concentration high enough for precipitation. Of course, then  
you're left with lots of BSA in your precipitate too....



On Mar 11, 2010, at 9:27 AM, Nikola Wenta wrote:

> Hi Iraz!
> I don't have any clue about acetone precipitation of proteins, but  
> generally, precipitation with saturated Ammonium sulfate solution  
> provides a good means to concentrate proteins and to get them into  
> a save state for short-term storage. Unfortunatelly, you would  
> already need the protein solution to be at > 1 mg/ml in order to  
> get it to precipitate. Thus, in your case this method doesn't seem  
> suitable. You could also try to concentrate the protein with  
> Centricons, but you would rather loose protein to the membrane than  
> concentrate your solution as it is already too diluted. Why not  
> loading maximum volume into biggest possible pockets on a gel with  
> maximum thick spacers? Additionally you could use a acrylamide  
> percentage that "compresses" your protein band, giving you a better  
> signals in WB.
> Best, Niko
>
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> Betreff: Methods Digest, Vol 58, Issue 7
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> Date: Thu, 11 Mar 2010 16:56:05 +0100
> From: "Iraz Toprak Aydin" <iraz.aydin from epfl.ch>
> Subject: Protein precipitation - acetone?
> To: <methods from magpie.bio.indiana.edu>
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>
> Dear all,
>
>
>
> I have to do a western blot, but my protein concentration is very  
> low, and I
> have to run a mini gel. So I was thinking of precipitation the  
> proteins. I
> have never done this before. Does acetone have a bad effect on the  
> blotting?
> Are there any points that I should be careful about?
>
>
>
> Thanks in advance...
>
>
>
> Iraz Toprak Aydin
>
>
>
> EPFL SV ISREC, Station 19
>
> Batiment SV, SV 2540
>
> CH-1015 Lausanne
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> Switzerland
>
>
>
> Tel: +41 21 693 07 36
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>
>
> e-mail:   <mailto:iraz.aydin from epfl.ch> iraz.aydin from epfl.ch
>
>
>
>
>
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Irit Rappley, PhD
The Scripps Research Institute
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10550 N Torrey Pines Rd.
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