- ChimeraX-users - RBVI Mailing Lists

Measure volume at multiple threshold levels not function
by Christian Tüting 22 Aug '22

22 Aug '22

Dear ChimeraX-Team, I have an issue with the volume measure tool. I would like to measure the volume at different thresholds. Using the gui mode, I can type the following: volume #1 level 1 measure volume #1 LOG: Enclosed volume for surface (#1.1) = 4.012e+06 volume #1 level 2 measure volume #1 LOG: Enclosed volume for surface (#1.1) = 2.144e+06 So this is functional in principle. But I would like to run this in no gui mode, so the commands are ";" seperated. But, even in gui mode, I got the following: (threshold was set to 1 before executing) volume #1 level 1; measure volume #1 LOG: Enclosed volume for surface (#1.1) = 4.012e+06 volume #1 level 2; measure volume #1 LOG: Enclosed volume for surface (#1.1) = 4.012e+06 So the threshold level is not applied, prior to the measurement of the volume. And this is the same in the no-gui mode. I would like to check the volume at 5 different levels, but I got always the same value when executing: "/usr/libexec/UCSF-ChimeraX-daily/bin/ChimeraX --nogui --cmd 'open cryosparc_P42_J241_002_volume_map_sharp.mrc; volume #1 level 0.5; measure volume #1.1; volume #1 level 0.5; measure volume #1.1; volume #1 level 0.5; measure volume #1.1; volume #1 level 1; measure volume #1.1; volume #1 level 1; measure volume #1.1; volume #1 level 1; measure volume #1.1; volume #1 level 1.5; measure volume #1.1; volume #1 level 1.5; measure volume #1.1; volume #1 level 1.5; measure volume #1.1; volume #1 level 2; measure volume #1.1; volume #1 level 2; measure volume #1.1; volume #1 level 2; measure volume #1.1; volume #1 level 2.5; measure volume #1.1; volume #1 level 2.5; measure volume #1.1; volume #1 level 2.5; measure volume #1.1' --exit" Is there any command, that the threshold level is somehow applied, and the measure volume is executed correctly? The problem is present in UCSF ChimeraX version: 1.4.dev202202240543 and UCSF ChimeraX version: 1.5.dev202207221833 Best Christian

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AlphaFold prediction of complex - results not downloaded
by Erik Werner 22 Aug '22

22 Aug '22

Ladies and Gentlemen, This weekend, I did an AlphaFold prediction run of the human Troponin complex (Troponin C, T and I, UniProt-Ids P63316, P45379, P19429, respectively) via a freshly installed ChimeraX (v 1.4)/Google Colab on macOS Catalina (10.15.7). It completed successfully after 8 hrs (see screenshot below) but I failed to locate the results. According to your tutorial (https://www.youtube.com/watch?v=6lXeCPuTePs and https://www.rbvi.ucsf.edu/chimerax/data/alphafold-dec2021/af_multimer.html) I was expecting the results in a Prediction#-folder within the Downloads folder, but ChimeraX had only saved the UniProt xml files there. Also, the notebook code indicated the download of a "results.zip" folder but that also cannot be found anywhere on the computer. What have I done wrong? Would I have to edit the notebook? Specify a folder, and where? And: can I still recover the results from Google Colab servers? I copied the notebook to my GoogleDrive but was unable to identify a run-id or anything specific to my run. I would really like to get this working as the prediction of complexes is such a fantastic resource! Many thanks for your help, Erik Werner, Berlin /--// //Dr. Erik Werner// //Paulstr. 36// //10557 Berlin// //Germany/

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Re: [chimerax-users] writing names of models as a text file
by Rangarajan, Amith 19 Aug '22

19 Aug '22

Dear Chimerax team, I want to access the names of the models in a individual chimerax session , i am not able to find a way to write them out as a txt file or to the log . please help me find a way to do this. thanks again for all your help, best amith

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Sym #1 command not executing
by John O'Brien 19 Aug '22

19 Aug '22

Hello, I am a new user to ChimeraX, and was doing the examples in the Quick Start Guide as practice. While following the Atomic Structure Commands, the "sym #1" command did not appear to produce the full table of symmetries, as described in the guide. Could you please help me with this? I have attached a screenshot of what I see to this email, hopefully that helps. Best, John O'Brien

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Re: [chimerax-users] Question about Coulombic scale bar in ChimeraX
by Elaine Meng 18 Aug '22

18 Aug '22

Hi Guipeun, This is the usual situation: The Color Key is not saying that -10 to +10 are the entire range in your structure, it is just showing how the color changes between -10 and +10. You would not change the values on the color key unless you also change the coloring. Any areas of the surface that have values beyond the range just get the same color as that end of the Color Key. I.e., all surface points with values below -10 (all the way down to the minimum for your surface -13.11) are the pure red shown at one end of the Color Key, and all surface points with values above 10 (up to the maximum for your surface +21) are the pure blue color shown at the other end. In between -10 and +10 the color gradually changes, and showing that change is the purpose of the Color Key. The tutorial uses "coulombic" with the default coloring, and the "key true" option in that command shows the values for that default coloring which are red for -10, white for 0, and blue for 10. <https://www.rbvi.ucsf.edu/chimerax/docs/user/tutorials/binding-sites.html#k…> If you used different value/color settings in the command, then the key would appear with those different settings. I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco P.S. it is recommended to send questions to chimerax-users(a)cgl.ucsf.edu (CC'd here) unless you are including data that needs to remain private > On Aug 18, 2022, at 12:14 PM, Guipeun Kang <Guipeun.Kang(a)UTSouthwestern.edu> wrote: > > Dear Dr. Elaine Meng, > > My name is Guipeun Kang, a postdoctoral researcher in Dr. Ryan Hibbs at UT Southwestern medical center. > > I have a silly question about scale bar of Coulombic surface. > > I displayed Coulombic potential of 3eeb, which is an example on ChimeraX tutorial page. > https://www.rbvi.ucsf.edu/chimerax/features.html > > In the Log, Coulombic values are minimum -13.11 and maximum 20.86 for chain A, but the scale bar is ranged from -10 to 10 when I add color key as shown in the instructions. > https://www.rbvi.ucsf.edu/chimerax/docs/user/tutorials/binding-sites.html#k… > > My question is: > When I type command "coulombic protein key true", the range of Coulombic surface of 3eeb is automatically reflected from -10 to 10? Or, should I manually change the scale bar range from -13 to 21 as shown in Log? > > I'm attaching a screenshot of ChimeraX Log and Color Key panel related to my question. > > I really appreciate your help, > Guipeun > > <image.png> > > UT Southwestern > Medical Center > The future of medicine, today.

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How to get back to original view after running resfit
by Rayees Mattoo 18 Aug '22

18 Aug '22

Hi, I am using resfit command. Is there a command or way to go back to the original view? Best, Rayees

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Rotate image on screen by 6 degrees?
by Robert Stroud 15 Aug '22

15 Aug '22

Is there a command that would rotate the image on screen (model and em map) by 6 degrees around the y axis? Im trying to make crossed eye stereo image for a paper, so I can then put the two images together in illustrator - as I see it Chimerax does not do crossed eye stereo, - and in stereo mode the center of rotation is not in the center of the image for me, so that the half images appear windowed differently on left and right? Thank you Robert Stroud stroud(a)msg.ucsf.edu <mailto:stroud@msg.ucsf.edu> 415 987 7535

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command question
by Kwangjun Lee 15 Aug '22

15 Aug '22

Hello, How can I adjust the position of the distance label? I figured out how to adjust the label for the residues. Thanks!

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Alternative locations
by Michael Bruist 15 Aug '22

15 Aug '22

In a demonstration page for students, I wish to show how the presence of the 2’OH on a ribonucleotide creates a clash at the active site of DNA polymerase. We are also trying to see if 2’OH’s create clashes within the primer. I have created a PDB file with deoxyribose as alternative location A and ribose as alternative location B. This works in original Chimera, but I am not getting it to work in ChimeraX. I am not able to specify the alternative atoms by their A and B designations. I do not see alternative locations in the hierarchy under target specification in the documentation. My PDB file is attached. Residues 106-113 have alternate locations included. The command “altlocs change A :113" does not seem to change anything, nor does changing the selection buttons in the Altexplorer. Mike Bruist mbruist(a)sju.edu

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docked UI
by Pranav Shah 13 Aug '22

13 Aug '22

Hi Team, Is there a way to make sure that some UI elements (eg. the chimerax python console) that I have enabled by calling from a custom startup script are pinned into the main window instead of appearing as floating windows? Best, Pranav -- Pranav Shah Postdoctoral Research Fellow. Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, Oxford OX3 7BN, UK

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ISOLDE download
by Jason Mears 12 Aug '22

12 Aug '22

I am trying to download the ISOLDE bundle for my ChimeraX software. I have been unsuccessful thus far. The download starts, but it never completes the download. I have tried a number of times and logged in using my university credentials thinking that this might help. Nothing yet. I am running OS Monterrey (v 12.5). Any advice is appreciated. Thanks. - Jason Mears -- Associate Professor of Pharmacology Graduate Program Director, Pharmacology Center for Mitochondrial Diseases Case Western Reserve Univ SOM 216-368-3348 jason.mears(a)case.edu <mears.jason(a)case.edu>

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Drag select blanks view window
by Daniel Asarnow 10 Aug '22

10 Aug '22

In ChimeraX 1.3 and now 1.4 releases, I have an issue where control-click dragging to select causes the 3D viewer frame to black out. Everything else functions normally, including the select itself, although it is very difficult to use since the structure can't be seen. The select box *is* visible, but it's magenta instead of green. Afterwards things go back to normal if something was box selected, but if nothing was boxed then the 3D viewer remains blacked out until an interaction like moving the models/camera takes place. I'm on a 2021 M1 MacBook Pro with macOS 12.4. I was wondering if others have experienced this and if it's an M1 issue as this is the only machine I've seen exhibit the problem. Best, -da

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Distance between two residues
by Kwangjun Lee 07 Aug '22

07 Aug '22

Hello, Do you have a command that measures the distance between two residues? For example, I have a dimer model, and I want to measure the distance between /A:100 and /B:200 Thanks! Kwangjun Lee Ph.D. Candidate Department of Biomedical Sciences Florida State University College of Medicine 1115 W. Call Street Tallahassee, FL 32306 Tel: (850) 491-6985 Email: kwangjun.lee(a)med.fsu.edu<mailto:hyojeong.yong@med.fsu.edu>

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maps not on same grid in new ChimeraX?
by Moritz, Michelle 06 Aug '22

06 Aug '22

Hello, I recently updated my ChimeraX to version1.4(2022-06-03). It seems that now when I open cryoEM maps they are not always opening on the same grid, although they have the same box and pixel size. As I recall, in previous versions of Chimera, maps with the same box and pixel size would open in a coordinated, overlapping fashion, and they would move together when manipulated. Is there a preference that I need to set in the latest version in order for this to happen? Thanks for your help, Michelle

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Find Residues From Specified Residue Numbers Help
by Myers, Jonathan 05 Aug '22

05 Aug '22

Dear ChimeraX Users, I'm learning how to use the Python API and I found the set of ChimeraX recipes and am trying to use the code featured on the "Find Residues From Specified Residue Numbers" page. I've run into the following issue: NameError: name 'structure' is not defined. I'm not sure what I should be using as an input for the "structure.residues" argument so I have not changed that input. What "structure" should I be specifying? Any help would be greatly appreciated. Shosholoza, Jonathan Myers

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Color by Chemical Shift Perturbations
by Nadun Chanaka Karunatilleke R Wasala Mudiyanselage Vihare 05 Aug '22

05 Aug '22

Hi admin, I am trying to color the protein surface based on the chemical shift perturbations. As mentioned in the example published on March 15th, 2021, I was able to color the surface. However, I needed to add 6 levels, and I failed to do so. It was possible to define the levels and colors in chimera but I failed to do so in chimerax. Is there a way to solve this? Thank you Nadun Nadun Karunatilleke Ph.D. Candidate Dr. James Choy's Lab Department of Biochemistry Schulich School of Medicine & Dentistry Western University London, Ontario, Canada N6A 5C1

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Use different distances for several marker sets
by SHIQING LIAO 04 Aug '22

04 Aug '22

Dear community, I'm wondering if there is any way for me to color a volume density with different distances from several marker sets. Thank you for your help! Best, Shiqing

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Time-efficient python code for obtaining coordinates of atoms
by Shubham Devesh Ramgoolam 03 Aug '22

03 Aug '22

Hi all, I hope you are doing well. I am looking for a time-efficient way of obtaining the coordinates of specified residues. I cannot use the command getcrd as I need these coordinates in a python script for defining geometric objects (getcrd prints the output to the log). My attempt at this consisted of selecting all of the specified residues via run(session, ‘sel ...’), accessing that selection using selected_residues(session), and then, extracting the coordinates using .atoms.coords. The issue here is that run(session, ‘sel ...’) slows down if there are lots of specified residues. I tried bypassing the command ‘sel’ by first importing AtomSpecArg from chimerax.core.commands.atomspec and then using AtomSpecArg.parse('my residue_ID', session)[0].evaluate(session).atoms[0]. However, this is even slower. Regards, Shubham Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows

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Error message
by Kwangjun Lee 03 Aug '22

03 Aug '22

Hello, I was trying to find residues within the dimerization interface. I have watched the video https://www.youtube.com/watch?v=TMcjEecFHaI&t=17s [https://i.ytimg.com/vi/TMcjEecFHaI/maxresdefault.jpg]<https://www.youtube.com/watch?v=TMcjEecFHaI&t=17s> Evaluating AlphaFold protein-protein binding with ChimeraX<https://www.youtube.com/watch?v=TMcjEecFHaI&t=17s> We show how to display AlphaFold predicted aligned error for residues at the binding interface between two proteins, encapsulin and ferritin, using ChimeraX.... www.youtube.com and follow the instructions but I got an error message and it seems others have the same issue with me. Is it a bug or did I do something wrong?? Thanks! Kwangjun Lee Ph.D. Candidate Department of Biomedical Sciences Florida State University College of Medicine 1115 W. Call Street Tallahassee, FL 32306 Tel: (850) 491-6985 Email: kwangjun.lee(a)med.fsu.edu<mailto:hyojeong.yong@med.fsu.edu>

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ChimeraX change chain IDs tool not available
by Rish, Anthony 02 Aug '22

02 Aug '22

Hello, I created a protein model with 9 separate chains and fit it to my experimental cryo-EM map. However, once I saved the new model, relative to the map, the chains were renamed to 1.1/A, 1.2/A… 1.9/A. This is no good since all chains now are labeled as A in the PDB file and programs like PyMol can’t tell the difference between the chains. I checked the ChimeraX user guide and there is supposed to be a tool for this exact problem called change chain IDs under the Tools->Structure Editing tabs, using the command changechains, but the tool is nowhere to be found. I’m running the current build of ChimeraX as of 8/2/22. How can I change the chain IDs of my model? Thanks, Anthony

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Sorting the required molecules in cvc file
by Dmitry Semchonok 02 Aug '22

02 Aug '22

Dear colleagues, I would like to find out about the possibilities. I have a model that contains apart from the other data, the pigment molecules – chlorophylls, carotenoids etc. Is there a way sort certain types of molecules in a *.cvc file by chimeraX so that the following information will be shown? Mol,Label,Element,X,Y,Z CHL,n 606,NC,267.342,151.989,253.363 CHL,n 606,MG,266.202,151.941,255.073 CHL,n 607,NB,275.512,153.952,252.428 CLA,n 610,MG,273.005,139.807,270.918 CLA,n 611,NB,288.916,127.885,266.725 Thank you! Kind regards, Dmitry

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Superposing protein structures
by Alicia Gardiol 02 Aug '22

02 Aug '22

We have experimental protein structures in PDB, and Alpha Fold predicted structures. Which is the best software to superpose these structures using a MAC computer. - Two different predicted proteins (predicted 1 to predicted 2) and - Same protein predicted and experimental (predicted 1 to experimental 1) Thank you and best wishes. Alicia Gardiol, PhD

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Re: [chimerax-users] Model panel for multi-state objects of dimeric protein
by Elaine Meng 01 Aug '22

01 Aug '22

Hi Enrico, I haven't figured out why this doesn't work on your example (omitted since mailing to the list): close #1 & ~ #1.5 However, this works: delete #1 & ~ #1.5 Also if you didn't have other models (#2 etc.) that you were trying to keep you could just use delete ~#1.5 I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco > On Aug 1, 2022, at 6:39 AM, Enrico Martinez <jmsstarlight(a)gmail.com> wrote: > > Hello Elaine, > I just faced the same problem that has been indicated in this topic > Thi time I am dealing with the monomeric multi-model complex obtained > from docking. > Here is the example of a pdb file consisted of 80+ docking poses. To > keep only the 1.5 sub-modeli've tried to use > close #1 & ~ #1.5 > but this produced nothing, while for other pdbs it works fine. Could > you tell me what's wrong with it? > Many thanks in advance > Cheers > Enrico

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Reduce figure size for export for publication
by Fossati, Andrea 01 Aug '22

01 Aug '22

Hi, How to best export figure at high-ish resolution to then add it to an already made illustrator panel? After some googling seems vector-based export is not possible so what is the recommended format and which resolution is best for 3x3 inch illustrator panel? At the moment I am exporting as TIFF with transparent background and size 5000 and supersampled 4 times to keep high res but the file has like 15Mb per structure which is not feasible/handy to modify. What is the suggested solution for paper figures? Best, Andrea Fossati, Ph.D Krogan Lab

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How to estimate 2dlabels fading?
by Edoardo D Imprima 01 Aug '22

01 Aug '22

Hi, Could you please explain more how the frames option works when changing 2dlabels? Let’s say I have 100 frames and I wish to have an arrow to appear at frame 10 for 5 frames? Many thanks in advance, Edoardo ------------------------------------------------------ Dr. Edoardo D'Imprima Postdoctoral fellow Structural and Computational Biology Unit EMBL Heidelberg - Mahamid Group Meyerhofstraße 1 69117 Heidelberg Germany Phone: +49 6221 387-8531

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