Hi, I am trying to do IP for a protein. I have added protease inhibitor tablet and PMSF, but my protein always was cleaved. Can I do anything to prevent the cleavage?

We also predicted the structure of this protein and found the cleavage sites likely are in non-structural regions (not in alpha-helix or beita-sheet). If we can't solve the problem during IP experiment, can we do something on the sequence?

The predicted size of the protein is 64KDa. In the picture, we can see two faint bands that are around 60KDa and some bands that are between 35 and 40 KDa. After IP, we only can get the 35-40 KDa bands.