(sending properly this time, rather than just to Rasmus) I don't believe a "color by RMS" option is in ChimeraX right now (I'll suggest it to the developers), but this will align all models then set B-factors for each residue to the RMS CA deviation from the mean position. Could be extended fairly trivially to do all-atom RMS if you wanted to. Change the extension for the attached text file to .py, open your NMR ensemble in ChimeraX, select all the models (typically just "sel #1" should do the trick), then use File/Open and choose color_by_rms.py (or just "open color_by_rms.py" on the command line if it's in your working directory). As long as all models have the same set of residues, it should do the trick. Example image for 2kv5 attached.
Have fun! -- Tristan ________________________________ From: CCP4 bulletin board <CCP4BB@JISCMAIL.AC.UK> on behalf of Harry Powell - CCP4BB <0000193323b1e616-dmarc-requ...@jiscmail.ac.uk> Sent: 26 May 2021 16:04 To: CCP4BB@JISCMAIL.AC.UK <CCP4BB@JISCMAIL.AC.UK> Subject: [ccp4bb] Analysis of NMR ensembles Hi Given that there are plenty of people on this BB who are structural biologists rather than “just” crystallographers, I thought someone here might be able to help. If I have a structure in the PDB (e.g. 2kv5) that is an ensemble of structures that fit the NOEs, is there a tool available that will give me some idea about the bits of the structure that do not vary much (“rigid”) and the bits that are all over the place (“flexible”)? Would superpose or gesamt be a good tool for this? Ideally I’d like something that could add a figure to the B columns in a PDB file so I could see something in QTMG (or PyMol if forced…) or do other useful things with the information. Harry ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB<http://www.jiscmail.ac.uk/CCP4BB>, a mailing list hosted by www.jiscmail.ac.uk<http://www.jiscmail.ac.uk>, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/ ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/
from chimerax.atomic import Residues, Atoms, selected_residues from math import sqrt import numpy models = selected_residues(session).unique_structures from chimerax.core.commands import run run(session, f'match {"|".join(["#"+m.id_string for m in models[1:]])} to #{models[0].id_string}') for residues in zip(*[m.residues for m in models]): residues = Residues(residues) pas = Atoms(residues.principal_atoms) if not len(pas): residues.atoms.bfactors = 0 continue coords = pas.scene_coords avg = numpy.mean(coords, axis=0) deviations = coords-avg distances = numpy.linalg.norm(deviations, axis=0) rms = sqrt(numpy.mean(distances**2)) residues.atoms.bfactors = rms run(session, f'color bfactor sel') ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/