Dear All:
I have a general question about protein- protein interactions. I have two
proteins, A and B. A is a disordered protein while B is a well folded protein.
The binding between A and B has been approved by GST-pull down assay
previously. The strange thing is I cannot get them bind if protein A were just
freshly prepared. However, if I kept these two proteins separately for one or
two days at 4 degree and then did the GST-pull down assay again, I can observe
very strong interaction between A and B.
Protein A doesn't contain any cys residue. I have already test certain
chemicals which might affect the interactions, for example, DTT and EDTA. These
chemicals seems to have no effect on the binding.
Although A is a disordered protein, does it need such long time to find its
proper conformation?
Do any people have similar experience? Any suggestions are greatly appreciated.
Thanks,
Dee
