degradation of proteins stored at -80 C ?

Dr Engelbert Buxbaum engelbert_buxbaum at
Tue Oct 22 02:52:00 EST 2002

teerachild at wrote:
> Hi, I'm working on brush border membrane proteins (BBMP)to identify Cry toxin receptor in mosquitoes. I have a problem with BBMP. I stored BBMP proteins at -80 C with the addition of cocktail-protease inhibitors. But after one month or so, when I did western blotting. I saw a cross-reactivity between anti-Cry toxin and SDS-PAGE separated BBMP without any put-in Cry toxin. How could that be? I faced this problem twice. I think I put in high amount of protease inhibitors as defined in the leaflet. Could you guys give any suggestion on my problem? Thanks for all replys.

Has that cross-reactivity been absent immediately after preparation?

Have you tried storing your samples in 50% glycerol without freezing? Or
freezing after addition of cryoprotectants like sucrose?

More information about the Proteins mailing list