Not sure if all the sirs will concur (and it might be a good idea to ask madams also), but the answer is probably no. As far as protonation state goes (guess that is what you are after, not oxidation), a better strategy may be to look into the bond lengths between the appropriate heavy atoms that are affected by it. Make sure that you refine without restraints imposed on a particular bond and see if its length is closer to the one corresponding to protonated or deprotonated state.
Cheers, Ed. On Mon, 2010-11-22 at 23:18 -0600, Kenneth Satyshur wrote: > Sirs: > > We are attempting to refine hydrogens on a ligand (which is 100 % occupied) > and > has ~ 40 heavy atoms (CNO). The data is 1.2 A, 325 AA, 83335 data points in > C2. > We have refined aniso and with H riding along (Rf= 17, R = 15) in CCP4. Can > we individually > refine the protons on the ligand? Let them run free with the others along for > the ride? > Or will they just run away at this > resolution? Can CCP4 even do this? Should we switch to Shelx or Phenix? > It is important to find out what the oxidation state is for the ligand at the > pH > we crystallized the protein and complex. > > thanks >
