Hello same topic well discussed here.

https://www.google.com/amp/s/www.researchgate.net/post/Separating_mbp_tag_from_cleaved_protein/amp

Good luck!

I would be concerned abut doing the amylose bead binding step without removing the ammonium sulfate because the high ionic strength of the ammonium sulfate might favor hydrophobic binding interactions with the resin rather than specific affinity interactions. If you want to avoid the delay of dialysis, you could resuspend the ammonium sulfate pellet in buffer and pass it through a PD-10 desalting column to get out most of the residual ammonium sulfate. Alternatively, you could just dilute the resuspended pellet with low-salt buffer sufficiently to get the residual ammonium sulfate concentration down to a low level.

I do plan to dilute. As of now I think I will dialyze if I have time, or dilute sufficiently. If I need my solution to precipitate protein to be 30% ammonium sulfate and I take off the supernantant and resuspend pellet in a buffer with no salt is the best assumption that the pellet is at 30%? Assume the highest concentration of ammonium sulfate possible? Based on what I could find online it seems the protein precipitates to exclude water and ammonium sulfate. Adam B Shapiro

There will be some ammonium sulfate left in the pellet, no matter how careful you are to remove all the supernatant. If the pellet is dissolved in a minimal volume of the buffer, the residual ammonium sulfate concentration could be quite high.

Thank you, I ended up taking the pellet from the ammonium sulfate step and resuspending in buffer with no ammonium sulfate to dilute the concentration. I then performed a dialysis step to remove any residual ammonium sulfate. After this step I was able to get binding to amylose beads.