Dear all, I am trying to construct a model with four HIS binding to a copper. I set the distance constraints for ND1--CU as 2.0 angstrom, but the distances between ND1 and CU of the constructed models are around 2.5 angstrom, it seems that the constraints failed. Acctually, when I checked the model, I found that the distances could be around 2.0 angstrom if CU was just moved a little bit. rsr.add(forms.gaussian(group=physical.xy_distance, feature=features.distance(at['ND1:13:X'],at['CU:43:Y']), mean=2.00, stdev=0.05)) rsr.add(forms.gaussian(group=physical.xy_distance, feature=features.distance(at['ND1:14:X'],at['CU:43:Y']), mean=2.00, stdev=0.05)) Could someone tell me what kinds of reasons could result in restraints failure? Thanks very much! All the best, Qinghua |