Hi Gaoyina, Maybe a stupid suggestion, but did the paper of the negative stain EM explain how the complex was prepared? That would be the first thing I would try.
Further, as Abbas explained, the complex may fall apart during gelfiltration. At least for analytical purposes, you could try to crosslink your dimer with glutardialdehyde and see how it behaves then during gelfiltration. It could also be that you have to co-express both proteins to get the dimer. Best, Herman -----Ursprüngliche Nachricht----- Von: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] Im Auftrag von ??? Gesendet: Dienstag, 18. Juli 2017 04:25 An: CCP4BB@JISCMAIL.AC.UK Betreff: [ccp4bb] suggestions are welcome Hi all , It has been reported the Negative stain EM of a protein A-B complex, but according to my gel filtration results (I purified A and B respectively for incubation) , I found that A could not bind to B, of course I tried different buffer condition with various pH value, even the binding condition only had 50 mm Kcl. Do you have any suggestion or methods that I can try to get the protein A-B complex? Any suggestion is welcome， Thank you all , Best,
