Hi there, The way to "fix" or "freeze" an entire section of a protein molecule will depend on the refinement program used. For example, in CNS, I would go to the = atom selection = section in the input file(s) and change the parameters there. You can fix atoms, or apply harmonic restraints. Restraining sufficiently is nearly equivalent to fixing... Other programs, you'd have to look in the respective manuals - am at home and it is difficult for me to access the relevant information for Phenix and Refmac.
Fred. > Message du 17/07/10 02:56 > De : "xinghua qin" > A : CCP4BB@JISCMAIL.AC.UK > Copie à : > Objet : [ccp4bb] how to fix a single helice > > Hi CCP4ers: > Recently I am trying to fix a helice, but found that it is so hard for > me because of the poor resolution(3.2A) and also a unvisible loop near it, > so is there any way to just fix a helice ? can I get it out of the whole > structure to refine it? > > Best regards > > -- > Xinghua Qin > College of Biological Sciences > No.2, Yuan Ming Yuan West Road > Haidian District，Beijing，China，100094 > Tel: +86-10-62732672 >
