Dear Lea and Andreas, given the excellent resolution, it might be possible to check the densities to decide if hydrolysis is the more likely cause. If the negative density starts more or less sharply after the C-terminal carboxylate group of the cleaved terminus (i.e. after the peptide nitrogen in the uncleaved part), this would favour cleavage as opposed to flexibility. I have never tried this, but maybe the refinement programs would allow for a refinement of the occupancies of the individual atoms of the last four residues to check if there is a clear drop right after the nitrogen atom.
Best wishes, Norbert ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/webadmin?SUBED1=CCP4BB&A=1
