[Chimera-users] problem related to open the chimera file by Coot

Dear All, I have fit a PDB file with a MRC by the Chimera. I saved both the fitted PDB file and the fitted MRC file by coot. When I open the fitted PDB file and the fitted MRC file by Chimera at the same time, they still fit perfectly. However when I open the Chimera fitted PDB file and the Chimera fitted MRC file by coot, the protein backbone (and the sidechains) does not fit the MRC file anymore. Will you please tell me what should I do in order to have the Chimera fitted PDB file and the Chimera fitted MRC file still fit in Coot? I am looking forward to getting your reply. Smith