[RASMB] Common contamination in recombinant protein preparation

[Dror Noy]

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