Dear Pascal, There can be a number of reasons for this. Maybe fos-cholines are not very well suited for your membrane proteins of interest? - have you checked for activity or aggregation and compared to other detergents? If the detergent is optimal you may consider moving/extending the tag or changing it to the other terminus. Also: do you have enough column material? Have you tried to mix the resin and protein in batch instead of passing it on the column? Have you tried to recycle the load during binding?
Poul On 13/07/2010, at 00.59, Pascal Egea wrote: > Dear All, > > I apologize for the not strictly crystallography-related query. > I am currently purifying several membrane proteins solubilized in > fos-cholines detergents and I consistently observe a significant loss of > protein at the binding step (done in absence of imidazole). Has anyone else > experience the same quite systematic (so far in my hands) problem with this > class of detergents. > I would appreciate any comments or advices from biochemists that face(d) the > same situation. > > Thanks in advance > > > -- > Pascal F. Egea, PhD > Assistant Professor > UCLA, David Geffen School of Medicine > Department of Biological Chemistry > 314 Biomedical Sciences Research Building > office (310)-983-3515 > lab (310)-983-3516 > email pe...@mednet.ucla.edu >
