- ChimeraX-users - RBVI Mailing Lists

distance between centers of mass using python API
by Diego Amaya 08 Sep '21

08 Sep '21

Hello, I'm trying to compute the distance between the centers of mass of two residues using the python API. I tried two different ways : 1. *rc(session, 'define centroid :43 massWeighting true name AA1')rc(session, 'define centroid :35 massWeighting true name AA2')rc(session, 'distance AA1 AA2') * 2. *rc(session, ' measure center :43 mark true name AA1')rc(session, 'measure center :35 mark true name AA2')rc(session, 'distance AA1 AA2')* But I get this error in the third line in both cases : *chimerax.core.errors.UserError: Missing or invalid "objects" argument: invalid objects specifier * What is wrong ? Thanks in advance. -- Diego A. Amaya Ramírez -- *Aviso legal:* El contenido de este mensaje y los archivos adjuntos son confidenciales y de uso exclusivo de la Universidad Nacional de Colombia. Se encuentran dirigidos sólo para el uso del destinatario al cual van enviados. La reproducción, lectura y/o copia se encuentran prohibidas a cualquier persona diferente a este y puede ser ilegal. Si usted lo ha recibido por error, infórmenos y elimínelo de su correo. Los Datos Personales serán tratados conforme a la Ley 1581 de 2012 y a nuestra Política de Datos Personales que podrá consultar en la página web www.unal.edu.co <http://www.unal.edu.co/>.* *Las opiniones, informaciones, conclusiones y cualquier otro tipo de dato contenido en este correo electrónico, no relacionados con la actividad de la Universidad Nacional de Colombia, se entenderá como personales y de ninguna manera son avaladas por la Universidad.

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Question about use of ChimeraX
by Jonathan Choong 07 Sep '21

07 Sep '21

Hi there, Hope you are doing well. I just had a question regarding ChimeraX that I was hoping to get some clarity on. I was wondering whether it was possible to use ChimeraX commands (such as open, run, save) in the system command line without actually opening the application interface? Thanks, hope to hear back from you. Kind regards, Jonathan

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Re: [chimerax-users] [Chimera-users] matchmaker for more than one chain
by Elaine Meng 03 Sep '21

03 Sep '21

Hi Mani, There is a different e-mail address for ChimeraX questions: it is chimerax-users(a)cgl.ucsf.edu CC'd here. Responses below... > On Sep 2, 2021, at 2:22 AM, manikandank via Chimera-users <chimera-users(a)cgl.ucsf.edu> wrote: > > Hi ChimeraX-users, > I have used recently the mmaker cmd to align two pdb each have multiple chains as below. > > mmaker #12/L,M,N to #5/S,A,B matrix blosum-62 showAlignment true > > But the sequence view shows only the alignment of chain L and S. > > 1. I would like to have aligned sequences of all chains used in mmaker alignement. Your command above does not use all the chains for fitting, it only chooses the single pair of chains that gives the best sequence-alignment score to superimpose the two models. The other chains might look superimposed but it is only because they moved along with the ones that were actually used for the fit. To use all three pairs of chains, you need to also use the "pairing ss" option: mmaker #12/L,M,N to #5/S,A,B matrix blosum-62 showAlignment true pair ss Then you would get three pairwise sequence-alignment windows: L/S, M/A, and N/B. matchmaker or mmaker command <https://rbvi.ucsf.edu/chimerax/docs/user/commands/matchmaker.html> pairing options <https://rbvi.ucsf.edu/chimerax/docs/user/commands/matchmaker.html#options> > > 2. Is it possible to open the saved RMSD header values in a file later just to color the pdb? Yes, but with several steps so it may not be that convenient. Probably easier just to save and restore the ChimeraX session (which includes the sequence alignment windows). Also remember if you move the structures relative to each other, the RMSD values will change. However, if you really want to save the RMSD values to file after you showed sequence alignments and header, then you could save them as an attribute file (that could be reopened/applied later): <https://rbvi.ucsf.edu/chimerax/docs/user/commands/save.html#attributes> The attribute name is seq_rmsd as explained here: <https://rbvi.ucsf.edu/chimerax/docs/user/tools/sequenceviewer.html#headers> > > 3. Do mmaker align entire pdb based on selected chains and Can calculate RMSD for all residues in the pdb? For the first question, 3A: yes, depending on the "pairing" option as explained above. For the second question, 3B, I'm not sure what you want. Remember that the main purpose of matchmaker is to superimpose the structures well, and then it happens to also give the RMSD over the positions that it chose to use, which are shown in the pinkish boxes on the sequence alignment. By default it uses fit iteration and discards loops that don't superimpose well in space. Matchmaker only gives the RMSD over the positions it uses. You could tell it to use all positions, but that would change the superposition. If you like the default superposition (that does not use all of the positions), you can use a separate command "rmsd" to measure RMSD over any sets of atoms that you want, without moving the structures or changing the superposition. Or, if you really want to use all of the positions in the sequence alignment for the fitting, you would have to use matchmaker option "cutoff none" ... but that usually does not give the best superposition. cutoff option <https://rbvi.ucsf.edu/chimerax/docs/user/commands/matchmaker.html#cutoffDis…> rmsd command (calculate RMSD in current positions, no fitting) <https://rbvi.ucsf.edu/chimerax/docs/user/commands/rmsd.html> Matchmaker only gives alpha-carbon RMSD. The rmsd command can give RMSD for any sets of atoms that you want, alpha-carbons only, or backbone only, or all atoms, as long as you give equal numbers of atoms from the two structures. However, it can be tricky to specify the correct sets of atoms if the residue numbering or residue types are different between the two structures. So you might want to first use "mmaker" with whichever options give you the best superposition, and then to measure RMSD over all positions in the alignment (which might not be used in the matchmaker fit), use the "rmsd" command afterward. > > 4. I also would like to change the displayed text for the sequence name. Presently it puts the filename as sequence name. > > [similar to 'Edit sequence name' in the sequence viewer in chimera] Sorry, there is no way yet to change the displayed sequence name in ChimeraX. > > Please let me know how this can be done. > thank you very much > with kind regards > Mani. I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco

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bundle dependency not installed
by Lagerwaard, I.M. (Ilse) 02 Sep '21

02 Sep '21

Hello, I'm currently developing a bundle with a dependency on pandas. Even though I included this dependency in my bundle_info.xml file, I get "ModuleNotFoundError: No module named 'pandas'". For now, I have installed pandas on the ChimeraX console via the command prompt. For future distribution, however, it would be nice if it were immediately installed together with the bundle. I would greatly appreciate your help with this issue. Thanks in advance, Ilse

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Re: [chimerax-users] output mmCIF file
by Elaine Meng 02 Sep '21

02 Sep '21

> On Aug 31, 2021, at 1:50 PM, Liu, Xiangan <Xiangan.Liu(a)uth.tmc.edu> wrote: > > Hi, > I have issue to output the models I build in pdb formation to mmCIF formation. I did not provide the sequences in orginal pdb files. Could please let me know what is the problem and how to fix it? > Thanks, > Xiangan > ---------- > File "/usr/lib/ucsf-chimerax/lib/python3.8/site-packages/chimerax/mmcif/__init__.py", line 89, in save > mmcif_write.write_mmcif(session, path, **kw) > File "src/mmcif_write.pyx", line 145, in chimerax.mmcif.mmcif_write.write_mmcif > File "src/mmcif_write.pyx", line 149, in chimerax.mmcif.mmcif_write.write_mmcif > File "src/mmcif_write.pyx", line 542, in chimerax.mmcif.mmcif_write.save_structure > KeyError: ('a1', 'RPGMMDSQEFS') > > KeyError: ('a1', 'RPGMMDSQEFS') > > File "src/mmcif_write.pyx", line 542, in chimerax.mmcif.mmcif_write.save_structure Hi Xiangan, We recommend using the chimerax-users(a)cgl.ucsf.edu address for questions (CC'd on this message, so you don't need to do anything this time). The address you used is just for commercial licensing. Actually, if you get a traceback like this, you can usually use ChimeraX menu: Help... Report a Bug instead of sending e-mail. You may need to attach your session file so that we can reproduce the problem. I don't know the answer, so I'm using this address to share your question with the others. Best, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco

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ChineraX saves huge session files
by Dror Noy 31 Aug '21

31 Aug '21

Hi Recently, ChimeraX on my Mac (macOS Catalina) started saving very large session file. Regardless of the size of the pdb file I load - the session file is 124 MB even for small 2-3 MB pdb files. I’d appreciate any help. Thanks Dror

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Region-wise specific sub-coloring of SS elements
by Gupta, Arun 30 Aug '21

30 Aug '21

Dear ChimeraX team, Is there an easier way around by which we can do region-wise specific sub-coloring of secondary structural elements within a large protein instead of using the tedious way of identifying the secondary structural elements and then describing the residue wise specific selection of set of residues related to secondary structure elements? I am aware that we can do coloring of specific secondary structure elements in ChimeraX by following commands for e.g “color helix “darkcyan” targ c”. But, I am looking forward to do coloring, let’ say “all the helices within a protein from residues 1-300 as dark cyan and residues 300-500 as blue” Thanks!!! Arun Arun Gupta PhD, MRSC Research Fellow Challis & Lewandowski Group Chemistry Department University of Warwick Gibbet Hill Road Coventry CV4 7AL United Kingdom

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Adding labels in chimera X?
by rob.gruninger＠gmail.com 27 Aug '21

27 Aug '21

I am trying to figure out how to add labels to a figure in chimeraX. It was easy in the older Chimera using 2d labels but I can’t find a similar function in chimeraX and the website seems to be down so I can’t access documentation. Any direction for how I can do this? I’m wanting to add residue labels to some specific residue (catalytic and substrate binding site residues) I want to point out in a paper Thanks Sent from my iPhone

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ChimeraX site down?
by Jonathan Sheehan 27 Aug '21

27 Aug '21

It might be pointless to send this query to the list (if it runs on the same server), but are you aware of any problems with your webserver right now? I'm trying to get the files for the latest density-fitting tutorial here: www.cgl.ucsf.edu According to this site, I'm not the only one having trouble reaching it: https://www.isitdownrightnow.com/cgl.ucsf.edu.html It claims it's "Down for everyone" and "for more than a week." Thanks! -Jonathan

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Save cropped map visible coordinates
by Isabelle Phan 26 Aug '21

26 Aug '21

Hello, I have 2 maps that I want to combine into a single one. I cropped each map by reducing the box size. I now want to save the map that is displayed. Impossible?! “Save” fails to keep the relative orientation of the display. I get 2 cropped maps that are no longer correctly oriented with respect to each other. "volume add” also fails to preserve the relative orientation. The volume resample sounds like it could be helpful, but I don’t understand how to get the grid values that match the displayed box. I’ve now tried multiple options for over 5 hours solid and am at my wits’ end. Any hints greatly appreciated. Isabelle

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ChimeraX Bundle
by Mirko Plößer 26 Aug '21

26 Aug '21

Dear ChimeraX Team, my name is Mirko Ploesser, I am a Phd student in the Frankgakis group at the BMLS (Buchmann Institue for Molecular Life Sciences) in Frankfurt (Germany) and currently working on a ChimeraX bundle. Thanks to your detailed tutorial on how to develop bundles, I have already made a good progeress in doing so. Currently, however, I am stuck with a problem that I hanve't found a solution to yet. I would be very thankful if you could give me advice on how to progress. The problem is described as follows: I click a set of markers in a volume (tomogram as an EM file) and save the corresponding positions. At those positions I want to load different and smaller volumes (also EM Files). The information about those smaller volumes - position and rotation - I have saved in a different file (a motivelist in also an EM format). Now I am stuck with the problem on how to update the rotation angles when I use the tool "Rotate model" using the right mouse. I know that the corresponding rotation matrix is printed in the log. Is there any way that I can use the information given to the log in my bundle code? Also, since we already have a working version of the bundle in Chimera, I found the module "openModel" very useful. Unfortunately I haven't been able to find an equivalent module in ChimeraX. So I guess there is a different approach to this used in ChimeraX. I would be very happy if you could also help me out in this regard. Thank you very much in advance for your time and effort. I am looking forward to hearing from you soon. Best, Mirko Ploesser

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How to make nucleotides same color?
by Visvaldas K. 25 Aug '21

25 Aug '21

I couldn't find how to change the default coloring of the nucleotides in ChimeraX. I'd like the color of all nucleotides to be blue like in the "old" Chimera: multiple colors distract from the details I am trying to convey. Is it possible? Best regards, Visvaldas

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ChimeraX File Error :: .vdb File Not Recognized
by Olivia Leland 24 Aug '21

24 Aug '21

Hello, I’m trying to upload a .vdb file from the Virus Particle Explorer databank. To my understanding, I should be able to upload a .vdb file for visualization. Every time I try to open said file, however, it returns the error: Is there a setting I haven’t activated in order to upload this file properly? Additionally, I’m unable to connect the software to the internet so I can’t use File>Fetch By ID... (it won’t show up for me) Do you have any suggestions on how to fix this? Best, Olivia Leland (she/her) Doctoral Student || Fraden Lab Martin A. Fisher School of Physics Brandeis University Waltham, MA 02453

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identifying surface residues
by Elaine Meng 23 Aug '21

23 Aug '21

On Aug 23, 2021, at 2:54 PM, Brian Yang <by2289(a)columbia.edu> wrote: > > Dear Dr. Meng, > I hope you are doing well. My name is Brian. I am a senior at Columbia University. I am currently doing research at the Columbia University Medical Center. I am contacting you because I have a few questions about using Chimera X. > > I am trying to use Chimera X to identify surface residues on a protein. [...] > > I have been looking through the Chimera API, and I found this method that I think could work: > https://www.cgl.ucsf.edu/chimera/docs/UsersGuide/surfnorm.html > > However, I'm not able to figure out how to do the Attribute Calculator in Chimera X, nor am I able to get the SES area. > > I saw your response in this email chain: > https://www.rbvi.ucsf.edu/pipermail/chimerax-users/2020-September/001484.ht… > > and I have tried it, but this is only for SAS area. > > So my questions are: > Do you think the surfnorm method is appropriate? If so, how would I achieve the Attribute Calculator functionality in Chimera X? If not, could you give me a better approach to remove these surface residues? > > Thank you for your time! > > Kind regards, > Brian Yang > Hi Brian! For asking questions about ChimeraX, we recommend using the address chimerax-users(a)cgl.ucsf.edu (CC'd here so you don't need to do anything this time) unless you are including something that needs to remain private. I edited out some details about your project above just in case. ChimeraX does not calculate solvent-excluded surface area (SESA) nor does it have an Attribute Calculator tool. However, if all you want to do is to identify which residues are on the surface, you could: (1) calculate solvent-accessible surface area (SASA) per residue. Command "measure sasa protein setAttribute true" or something like that. The "protein" part is that so waters, ligands, etc. are not enclosed in the calculated surface. The "setAttribute true" part assigns values to a residue attribute named "area" so that you can do the next step, although it could be omitted since it is already true by default. There are various other options too. <https://rbvi.ucsf.edu/chimerax/docs/user/commands/measure.html#sasa> (2) delete all residues with SASA greater than some value. You wouldn't be normalizing to a percentage exposed since we don't have the values to use for the denominator, but just the raw amount of solvent-accessible area. So you may want to tinker around with what value of the cutoff gives you reasonable results. <https://rbvi.ucsf.edu/chimerax/docs/user/commands/select.html> <https://rbvi.ucsf.edu/chimerax/docs/user/commands/atomspec.html#attributes> Example: open 4hvp measure sasa protein setAttribute true show hide ~protein hide ribbons sel ::area>20 color sel red color ~sel white ~sel ... see what you think, or try some other value... sel ::area>15 color sel red color ~sel white ~sel When you figure out what value you want to use, you could delete those residues, e.g. delete ::area>15 ...or if you're not sure what to use as a single cutoff and may want to process several times at different cutoffs, you can just write out all of the residues and their area values to an "attribute file"... see <https://rbvi.ucsf.edu/chimerax/docs/user/commands/save.html#attributes> However, if you really need a % exposure value normalized to account for different residue sizes, you would need to stick with Chimera, at least for now. I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco

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Labelling w.r.t Residue description
by Gupta, Arun 23 Aug '21

23 Aug '21

Dear ChimeraX team, How can we label the PDB structure in ChimeraX based on the selection as well as "description or residue type". I tried the specific "residues selection" for a PDB structure first and then typed the following command "label @ca residues attr residuename". I could get the residue numbering for the selected residues. But, I failed to get the residue description for the specific selected residues such as "residue 59 should be labelled as His59". Also, I noticed the "size " of the residue numbers "label " is bit small. How can we increase the " font size" ? Please find attached pic. Thanks!!! Arun Arun Gupta PhD, MRSC Research Fellow Challis & Lewandowski Group Chemistry Department University of Warwick Gibbet Hill Road Coventry CV4 7AL United Kingdom

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ChimeraX for Windows 10 Not Starting
by Mason Long 20 Aug '21

20 Aug '21

Hi, We're having problems getting ChimeraX to run on Windows 10 21H1. Each time we try running it, the cursor spins for a second or so and then nothing happens. I checked the Event Viewer and see every time we try running it an error event shows up in the Windows Application Error Event Log. Here's the output that shows up in the log for each of those versions: ---------------------------------------- Faulting application name: ChimeraX.exe, version: 1.2.5.0, time stamp: 0x60ab2a1d Faulting module name: Qt5WebEngineCore.dll, version: 5.15.2.0, time stamp: 0x5fad38ab Exception code: 0x80000003 Fault offset: 0x000000000014baff Faulting process id: 0x2b14 Faulting application start time: 0x01d795f43b7d3176 Faulting application path: C:\Program Files\ChimeraX 1.2.5\bin\ChimeraX.exe Faulting module path: C:\Program Files\ChimeraX 1.2.5\bin\lib\site-packages\PyQt5\Qt\bin\Qt5WebEngineCore.dll Report Id: db7d3af7-6986-47ed-ba27-3ce5e6bfcbae Faulting package full name: Faulting package-relative application ID: ---------------------------------------- Faulting application name: ChimeraX.exe, version: 1.1.0.0, time stamp: 0x5f5afaf7 Faulting module name: Qt5WebEngineCore.dll, version: 5.12.9.0, time stamp: 0x5ee3364a Exception code: 0x80000003 Fault offset: 0x0000000001989fb3 Faulting process id: 0x25d4 Faulting application start time: 0x01d795f5be3a354e Faulting application path: C:\Program Files\ChimeraX 1.1\bin\ChimeraX.exe Faulting module path: C:\Program Files\ChimeraX 1.1\bin\lib\site-packages\PyQt5\Qt\bin\Qt5WebEngineCore.dll Report Id: 5284e8f0-d191-4d3d-a49f-a93dc84117b0 Faulting package full name: Faulting package-relative application ID: ---------------------------------------- Faulting application name: ChimeraX.exe, version: 1.3.0.0, time stamp: 0x611f7fb2 Faulting module name: Qt5WebEngineCore.dll, version: 5.15.2.0, time stamp: 0x5fad38ab Exception code: 0x80000003 Fault offset: 0x000000000014baff Faulting process id: 0x2940 Faulting application start time: 0x01d795f6781afa93 Faulting application path: C:\Program Files\ChimeraX 1.3.dev202108200941\bin\ChimeraX.exe Faulting module path: C:\Program Files\ChimeraX 1.3.dev202108200941\bin\lib\site-packages\PyQt5\Qt\bin\Qt5WebEngineCore.dll Report Id: c07bfcd1-8b63-4e87-9217-a1a77cc449f8 Faulting package full name: Faulting package-relative application ID: ---------------------------------------- As you can see, this happens on both of the most recent production versions of ChimeraX (1.2.5 and 1.1.0.0) as well as on the latest daily build (1.3.dev202108200941) as of 8/20/2021. Please let me know if there's any more information you need from us. Thanks, Mason -- Mason Long Information Technology Consultant ITS Client Technology Natural Resources Building 211C Humboldt State University 1 Harpst St. Arcata, CA 95521 (707) 826-5636 (email only for now) Create a new request for help at http://www.humboldt.edu/ithelp

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Re: [chimerax-users] Automated Fitting of models into maps and saving fits with a correlation score > X
by Tom Goddard 18 Aug '21

18 Aug '21

Hi Matthias, When opening a script with the forEachFile option you can use $file in the script which will be replaced by the file basename. So in your script use fitsearch #2 in #1 resolution 20 search 1000 cutoff 0.9 save Tomo_fitted_$file_%d.pdb This is described in the forEachFile documentation https://www.rbvi.ucsf.edu/chimerax/docs/user/commands/open.html#forEachFile <https://www.rbvi.ucsf.edu/chimerax/docs/user/commands/open.html#forEachFile> Tom > On Aug 18, 2021, at 7:57 AM, Vorländer,Matthias Kopano <matthias.vorlaender(a)imp.ac.at> wrote: > > Dear Tom, > > Thank you again for the code for saving PDBs above a certain correlation score sing the fitmap command! I am now trying do use this on a large number of input volumes, and it’s working well except that I have a problem with naming the saved PDBs. So, my approach is the following: > > Open ChimeraX_Daily in no-gui mode > Type “open FitPDBinVolume.cxc foreach *.mrc” > The script FitPDBinVolume.cxc is very simple and looks like this: > > open 7apk > open /Volumes/matthias.vorlaender/Scripts/Chimera/fit_search.py > fitsearch #2 in #1 resolution 20 search 1000 cutoff 0.9 save /Volumes/plaschka/shared/data/em/Krios/20210616_endoTHO_tomo/Visualisation/mapping_back_using_imod/test/Tomo_fitted_%d.pdb > > What I would like to achieve is that the fitted PDBs are saved with a base name that matches that of the opened .mrc. Is there an easy way to do that? > > Thanks a lot in advance, > Best, > Matthias > > > From: ChimeraX-users <chimerax-users-bounces(a)cgl.ucsf.edu <mailto:chimerax-users-bounces@cgl.ucsf.edu>> on behalf of "Vorländer,Matthias Kopano via ChimeraX-users" <chimerax-users(a)cgl.ucsf.edu <mailto:chimerax-users@cgl.ucsf.edu>> > Reply to: "Vorländer,Matthias Kopano" <matthias.vorlaender(a)imp.ac.at <mailto:matthias.vorlaender@imp.ac.at>> > Date: Tuesday, 27. July 2021 at 07:40 > To: Tom Goddard <goddard(a)sonic.net <mailto:goddard@sonic.net>> > Cc: "chimerax-users(a)cgl.ucsf.edu <mailto:chimerax-users@cgl.ucsf.edu>" <chimerax-users(a)cgl.ucsf.edu <mailto:chimerax-users@cgl.ucsf.edu>> > Subject: Re: [chimerax-users] Automated Fitting of models into maps and saving fits with a correlation score > X > > Hi Tom, > > Thanks so much, that's amazing! > > To be clear, I am not searching tomograms, I am searching artificial tomograms that contain perfect "molmaps" of my protein of interest, so they are free of noise. Trying this in Chimera gave very good fits when asking for for enough initial placement. > > Thanks a lot for your help, > Best, > Matthias > > Holen Sie sich Outlook für Android <https://aka.ms/AAb9ysg> > > From: Tom Goddard <goddard(a)sonic.net <mailto:goddard@sonic.net>> > Sent: Tuesday, July 27, 2021 12:15:13 AM > To: Vorländer,Matthias Kopano <matthias.vorlaender(a)imp.ac.at <mailto:matthias.vorlaender@imp.ac.at>> > Cc: chimerax-users(a)cgl.ucsf.edu <mailto:chimerax-users@cgl.ucsf.edu> <chimerax-users(a)cgl.ucsf.edu <mailto:chimerax-users@cgl.ucsf.edu>> > Subject: Re: [chimerax-users] Automated Fitting of models into maps and saving fits with a correlation score > X > > Hi Matthias, > > You can run ChimeraX command scripts or Python scripts without a GUI, just start it at the shell with the "--nogui" option, for example > > chimerax --nogui mycommands.cxc > > I made some example Python code that runs fitmap search and saves PDB files for each unique fit with correlation over 0.9. > > https://rbvi.github.io/chimerax-recipes/fit_search/fit_search.html <https://rbvi.github.io/chimerax-recipes/fit_search/fit_search.html> > > I don't expect this to be a good way to search tomograms. It will be very inefficient. Template matching code designed for that problem is likely to work much better. Such code usually uses Fourier space methods to search all translations at once, so it can be much faster and more thorough. Even with that optimization it takes a long time to do the rotational search. > > Tom > > Example search of monomers in 14-mer GroEL. > > > > > > On Jul 25, 2021, at 9:05 AM, Vorländer,Matthias Kopano via ChimeraX-users <chimerax-users(a)cgl.ucsf.edu <mailto:chimerax-users@cgl.ucsf.edu>> wrote: > > Dear all, > > I have a set of 100 “artificial” tomograms, each containing approx 100 copies of a simulated density map of my protein of interest. I would like to fit each tomogram with the PDB of my POI, and save copies for all fits with a correlation score > 90%. Using the fitmap command in Chimera and then manually selecting the fits that meet the criterium works, but takes quiet a long time for a larger amount of data. I wonder if this could be automated, and if somehow would be able me to put together a script (is it possible to execute such tasks in a non-gui way, by submitting it to a cluster so that it could be parallelized?). > > Thanks a lot in advance, > Best, > Matthias > _______________________________________________ > ChimeraX-users mailing list > ChimeraX-users(a)cgl.ucsf.edu <mailto:ChimeraX-users@cgl.ucsf.edu> > Manage subscription: > https://www.rbvi.ucsf.edu/mailman/listinfo/chimerax-users <https://www.rbvi.ucsf.edu/mailman/listinfo/chimerax-users> >

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Re: [chimerax-users] How to adjust chimeraX's loop display style?
by Elaine Meng 17 Aug '21

17 Aug '21

Hi Xiangan, Sorry no, there is no way to smooth the loops (coil) parts of a ribbon or cartoon. Currently only strands can be smoothed. By "smoothed" I mean that the path of the ribbon may not follow the CA atoms exactly, which can cause problems when the sidechains are displayed. In Chimera when the sidechains were displayed with ribbon, you could get unrealistically long or short CA-CB bonds. So in ChimeraX we decided it was more important to have an accurate CA-CB bond length when sidechains are displayed. In the helix and coil (loop) there is no smoothing option so the ribbon is exactly on the CA positions. Strands have a smoothing option turned on by default, because people expect them to be drawn as mostly straight, and if strands are not smoothed, they are very ripply. In ChimeraX when the strands are smoothed but sidechains are shown, the CA atoms that fall off the ribbon are shown with a connecting "tether" instead of stretching or shrinking the CA-CB bond artificially. This is discussed in the "cartoon" help, see the "smooth" for how to adjust strand smoothing and "cartoon tether": <https://rbvi.ucsf.edu/chimerax/docs/user/commands/cartoon.html> <https://rbvi.ucsf.edu/chimerax/docs/user/commands/cartoon.html#tether> I investigated whether I could make a smoother representation with the "shape tube" command, but was unsuccessful. Sorry for the inconvenience -- I'm hoping that explaining the reasons might make it less annoying. :-) Best, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco > On Aug 17, 2021, at 1:12 PM, Liu, Xiangan <Xiangan.Liu(a)uth.tmc.edu> wrote: > > Hi, > ChimeraX's default loop style shows very cursive. I like the way loop shows in chimera. > Is there any way to make chimeraX's loop display straighter? > Thanks, > Xiangan > > <image.png>

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Chimerax for Ubuntu 21.04
by jobiph 17 Aug '21

17 Aug '21

Dear all, thank you for your fast and thorough answers. I reinstalled lifbffi7 and libllvm6.0 and now Chimerax works. Thanks a lot! Kind regards Jonas

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Re: [chimerax-users] Chimerax for Ubuntu 21.04
by Gabriel Goetten 16 Aug '21

16 Aug '21

Hi, I was able to run chimeraX on ubuntu 21.04 by installing the following package https://answers.launchpad.net/ubuntu/hirsute/amd64/libllvm10/1:10.0.1-6 Then you just need to download chimerax of the following version Ubuntu 20.04 (Linux) 64-bit from their website (deb package). Gabriel

1 0

Chimerax for Ubuntu 21.04
by jobiph 16 Aug '21

16 Aug '21

Dear all, is the current version of Chimera for Ubuntu (20.04) compatible with the 21.04 Ubuntu release? If i try to install the 20.04 version a weird dependency error pops up and I can't install the missing library because on the canonical website it states that this library is deprecated. Thank you for your help and kind regards Jonas

4 3

All-numeric residue names
by Tristan Croll 16 Aug '21

16 Aug '21

Was just looking at 2rg6, which happens to have a ligand with an all-numeric 3-character ID (287)... clearly not much thinking went into allowing that. Anyway, does the residue selection syntax have a way to disambiguate residue *number* 287 from residue *name* 287?

3 3

Coulombic color combined surface
by W. C. 13 Aug '21

13 Aug '21

ChimeraX has no way to color ONE continous surface formed by combining multiple chains with coulombic or hydrophobic. It always color each chain surface separatly . Even though I generated a surface of combined chains by "surface enclose" command, ChimeraX still colors each chian seperately. In Chimera (not ChimearX), I could use surfcat to combine chains, generate one surface for combind chains, and color the surface as one continous. However, that could color large set of molecules. So please make ChimeraX can do the same.

3 3

(no subject)
by Haaris Ahsan Safdari 12 Aug '21

12 Aug '21

Rrg together with the university international realty of

1 0

Morphing with ligands
by Volodymyr Dvornyk 10 Aug '21

10 Aug '21

Dear Colleagues, Tried to do morphing of the following structures: 6rdc, 6rep, and 6rd9. All three have the same ligands: ADP, ATP, Mg, and Zn. However, the resulting model lacks all of them. Any thoughts and/or suggestions? Thank you. Volodymyr ________________________________ DISCLAIMER: This electronic mail transmission contains confidential information intended only for the person(s) named. Any use, distribution, copying or disclosure by any other person is strictly prohibited. If you received this transmission in error, please notify the sender by reply e-mail and then destroy the message. Opinions, conclusions, and other information in this message that do not relate to the official business of Alfaisal University shall understand to be neither given nor endorsed by Alfaisal University. The contents of any attachment to this e-mail may contain software viruses, which could damage your own computer system. While "Alfaisal University" has taken every reasonable precaution to minimize this risk, we cannot accept liability for any damage which you sustain as a result of software viruses. You should carry out your own virus checks before opening the attachment.

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Trying to open .py files on Windows gives cPickle error
by Carnes, Jason 09 Aug '21

09 Aug '21

Hello, I am collaborating with someone using ChimeraX on a Mac. Their only option to save modified files results in a .py file extension. When I try to open .py files on my Windows install of ChimeraX I get an error: "ModuleNotFoundError: No module named 'cPickle'" Is there a way to manually install cPickle on my Windows computer that will allow me to open the .py files, or are Mac & PC not compatible? Thanks, Jason Jason Carnes, PhD Research Scientist IV | Center for Global Infectious Disease Research Seattle Children's Research Institute 206-884-3137 OFFICE CONFIDENTIALITY NOTICE: This e-mail, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information protected by law. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message.

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Difficulties Visualizing Isosurfaces from Cube File - Nathan Wood
by Nathan Wood 09 Aug '21

09 Aug '21

Dear ChimeraX I was having difficulty attempting to visualize computationally generated electrostatic potential isosurfaces originating from a Gaussian *.cube file. I tried to open the cube file from the shell only for it to incompletely visualize. I can provide an image if necessary. I found the following correspondence concerning cube files and isosurfaces, but unfortunately I am unable to resolve the issues of the cube file visualizing. https://www.rbvi.ucsf.edu/pipermail/chimerax-users/2021-April/002126.html <https://www.rbvi.ucsf.edu/pipermail/chimerax-users/2021-April/002126.html> https://www.rbvi.ucsf.edu/pipermail/chimerax-users/2020-May/001110.html <https://www.rbvi.ucsf.edu/pipermail/chimerax-users/2020-May/001110.html> I was curious if anyone has had experience with cubefiles. Any assistance would be greatly appreciated, Very Respectfully, Nathan Wood

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Superimpose
by Wisoot Chanit 08 Aug '21

08 Aug '21

Dear ChimeraX team, I am having a quesition. I am going to superimpose 2 monomers of P domain of norovirus GII.3 into a template PDB 6if5, but the template showed that information of its chains are missing. What should I do to make a dimer into 6if5. This is different from PDB 3mfg, which was a templete I used for my previous paper. Thank you. Jay

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Re: [chimerax-users] Saving 300dpi high resolution images with ChimeraX
by Elaine Meng 04 Aug '21

04 Aug '21

Hi Nada, ChimeraX questions should be sent to chimerax-users(a)cgl.ucsf.edu (CC'd here so you don't need to do anything this time). ChimeraX does not set the dpi. You just figure out the number of pixels you need and then save in pixels. I.e. if you want 3 inches wide at 600 dpi then you know you need 1800 pixel width, e.g. save myfile.png width 1800 If you open the resulting image file in just about any general image application like Photoshop, Gimp, or Mac Preview (etc.) then you can set the "resolution" or "dpi", but it's really the number of pixels you save in the first place that matters. 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 4, 2021, at 10:04 AM, Bejar, Nada <nbejar(a)houstonmethodist.org> wrote: > > Hello, > I am Nada, a postdoctoral fellow at Houston Methodist. > > I saw your name in this thread. https://www.rbvi.ucsf.edu/pipermail/chimerax-users/2020-January/000816.html > I tried your suggestion, but any number I put on width would still give me a 96dpi. > > I switched to the old Chimera and I can change the unit to print unit and that resolves the issues, but I have all my work done on ChimeraX. > > I do need to make figures today and help would be much much appreciated. > > Nada Bejar, Ph. D. > Postdoctoral Fellow > Kiss RNA Lab > Houston Methodist Research Institute > 6670 Bertner Avenue > Houston, TX 77030 USA

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Re: [chimerax-users] Error in ChimeraX application installation linux ubuntu
by Elaine Meng 04 Aug '21

04 Aug '21

Hi Vanessa, Please send ChimeraX questions to chimerax-users(a)cgl.ucsf.edu (CC'd here, so no need to do anything this time). Since I don't know the answer, I kept waiting for somebody else to answer your question... and didn't notice until now that you had sent it to only me. Thanks, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco > On Aug 1, 2021, at 1:51 AM, Vanessa Roy <vanessaroy(a)mail.tau.ac.il> wrote: > > Dear ChimeraX development team, > > We encountered issues while installing ChimeraX on our server and wanted to ask whether you could help us understand what the problem is? We haven't yet found a solution to our problem. > Here is the output after installation: > > # /home/apps/chimerax-1.2.5-rc-2021.05.24/bin/ChimeraX > X11 connection rejected because of wrong authentication. > qt.qpa.xcb: could not connect to display localhost:10.0 > qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found. > This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem. > > Available platform plugins are: eglfs, linuxfb, minimal, minimalegl, offscreen, vnc, wayland-egl, wayland, wayland-xcomposite-egl, wayland-xcomposite-glx, xcb. > > Fatal Python error: Aborted > > Current thread 0x00007f479c05d740 (most recent call first): > File "/home/apps/chimerax-1.1/lib/python3.7/site-packages/chimerax/ui/gui.py", line 119 in __init__ > File "/home/apps/chimerax-1.1/lib/python3.7/site-packages/ChimeraX_main.py", line 500 in init > File "/home/apps/chimerax-1.1/lib/python3.7/site-packages/ChimeraX_main.py", line 919 in <module> > File "/home/apps/chimerax-1.1/lib/python3.7/runpy.py", line 85 in _run_code > File "/home/apps/chimerax-1.1/lib/python3.7/runpy.py", line 193 in _run_module_as_main > Aborted (core dumped) > > We would greatly appreciate your advice on how to solve this issue. > > Many thanks for your help! > > Best, > Vanessa > -- > Vanessa Roy > Gil Ast Lab > Department of Human Molecular Genetics and Biochemistry > Sackler Faculty of Medicine | Tel Aviv University

4 3

Maps comparison
by Dmitry Semchonok 04 Aug '21

04 Aug '21

Dear colleagues, I have 2 cryo-em maps of different resolutions. What will be the correct strategy to compare them and what are the tools and steps? Thank you Sincerely, Dmitry

2 1

C-alphas rendered as dots
by Pranav Shah 03 Aug '21

03 Aug '21

Hi Team, I am working with a huge model (and a correspondingly huge map), which makes the handling on my GPU accelerated desktop an agonisingly frustrating experience. In order to speed up simple (rigid-body) fitting of the map and model, I decided to use the -C-alpha trace of the pdb. However, the pdb gets rendered as a bunch of disconnected dots whereas the same pdb in Chimera is rendered correctly with all things. Is this a normal behaviour for ChimeraX? I could use Chimera, but I prefer the way ChiemraX handles large maps as compared to Chimera. In the absence of a quick fix, would there be a way to increase the size of the atoms? 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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Showing C-alphas
by Casey 30 Jul '21

30 Jul '21

I am trying to show a single sphere at c-alpha carbons for some point mutants that i designed. When I use the command: show /a:473,476,477 atoms I can see all the atoms in chain A for residues 473, 476, 477. Using: show /a:473,476,477@cb atoms I can show "two spheres" for the c-alpha and c-beta carbon. When I use: show /a:473,476,477@ca atoms nothing happens and i don't see any spheres. If I show the full atom and then do: hide /a:473,476,477@ca* atoms Just the c-alpha sphere gets hidden. Why is it that i can't just show the c-alpha spheres? Unfortunately for my figure i make silhouettes of my model and so i can't just hide the other atoms by making them fully transparent

2 1

Re: [chimerax-users] Automating Map segment
by Tom Goddard 30 Jul '21

30 Jul '21

To group by connectivity looks like you need to add d._group_con.value = True To figure out this stuff you would need to look at the Segger user interface code, it is in the ChimeraX distribution (under site-packages/chimerax/segger/segment_dialog.py) or on GitHub https://github.com/tomgoddard/segger/blob/master/Segger/src/segment_dialog.… <https://github.com/tomgoddard/segger/blob/master/Segger/src/segment_dialog.…> Tom > On Jul 30, 2021, at 10:42 AM, Sam W Marchant <smarchant(a)UCSD.EDU> wrote: > > Thanks so much im trying to group by connectivity and I am having trouble finding the right line of code to add that ability. Any thoughts? > >> On Jul 29, 2021, at 3:56 PM, Tom Goddard <goddard(a)sonic.net <mailto:goddard@sonic.net>> wrote: >> >> Hi Sam, >> >> I did an initial port of Segger from Chimera to ChimeraX (also called Segment Map) but that code was written by Greg Pintilie and he has not worked the ChimeraX version so there is no new command to run it in a script. It would probably not be too hard to write some Python to run it. The Chimera script mentioned in the mailing list is attached to my message about it. >> >> https://plato.cgl.ucsf.edu/pipermail/chimera-users/2017-October/013979.html <https://urldefense.proofpoint.com/v2/url?u=https-3A__plato.cgl.ucsf.edu_pip…> >> >> That won't work in ChimeraX, but here I attach the equivalent for ChimeraX. >> >> Segger was developed to segment molecules in EM maps, so I have doubts that it will do much good for your light microscopy. But you can decide that by running it by hand on some time steps and see if you like the result. >> >> Here is a different approach we used to quantify protrusions of crawling neutrophils in light sheet microscopy by placing markers that might be of interest. >> >> https://www.cgl.ucsf.edu/chimera/data/protrusion-sep2015/protrusions.html <https://urldefense.proofpoint.com/v2/url?u=https-3A__www.cgl.ucsf.edu_chime…> >> >> Tom >> >> >> >>> On Jul 29, 2021, at 3:24 PM, Sam W Marchant via ChimeraX-users <chimerax-users(a)cgl.ucsf.edu <mailto:chimerax-users@cgl.ucsf.edu>> wrote: >>> >>> Hi, >>> I am looking to apply the Map Segmenting to multiple time series of light sheet imaging and so I was wondering if there is either a command or a python function to automate the process. It looks here <https://urldefense.proofpoint.com/v2/url?u=http-3A__plato.cgl.ucsf.edu_pipe…> that you said it was going to be added to ChimeraX but I cannot find any info on how to do it. If not you mentioned a script in this answer, could you potentially send that to me? >>> Thanks, >>> Sam Marchant. >>> _______________________________________________ >>> ChimeraX-users mailing list >>> ChimeraX-users(a)cgl.ucsf.edu <mailto:ChimeraX-users@cgl.ucsf.edu> >>> Manage subscription: >>> https://www.rbvi.ucsf.edu/mailman/listinfo/chimerax-users <https://urldefense.proofpoint.com/v2/url?u=https-3A__plato.cgl.ucsf.edu_mai…> >> >> <segscript.py> >

1 0

How to Align Chromosome Models with Different Number of Atoms?
by Cardiff Jiang 30 Jul '21

30 Jul '21

Dear ChimeraX User List, How can I compare two chromosome 3D models (PDB files) that have different numbers of "atoms"? Matchmaker tool reports, "Reference and/or match model contains no nucleic or amino acid chains. Use the command-line 'align' command to superimpose small molecules/ligands." align #1 toAtoms #2 reports, "Unequal number of atoms to pair, 49 and 63." align #1 toAtoms #2 matchNumbering true reports, "Pairing dropped 49 atoms and 63 reference atoms. No atoms paired for alignment." align #1:1-40 to #2:1-40 reports, "No atoms paired for alignment." How should I compare two chromosome 3D models below? Thank you. [image: image.png] Best regards, Zichen "Cardiff" Jiang

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Automating Map segment
by Sam W Marchant 29 Jul '21

29 Jul '21

Hi, I am looking to apply the Map Segmenting to multiple time series of light sheet imaging and so I was wondering if there is either a command or a python function to automate the process. It looks here<http://plato.cgl.ucsf.edu/pipermail/chimera-users/2017-October/013980.html> that you said it was going to be added to ChimeraX but I cannot find any info on how to do it. If not you mentioned a script in this answer, could you potentially send that to me? Thanks, Sam Marchant.

2 1

Re: [chimerax-users] command line way for inverting selection
by Rangarajan, Amith 29 Jul '21

29 Jul '21

Hi, I am looking for a way to invert selection without reaching for the tool bar. I would like to know if there is a way to invert selection via the select command ( or some other command) thanks a lot, Amith

3 3

ATOM has no alt loc B
by James Loy 28 Jul '21

28 Jul '21

Hi folks- I'm trying to add hydrogens to an mmCIF file (5byl) using the addh command. However, every time I try, I encounter the following error: Traceback (most recent call last): File "/usr/lib/ucsf-chimerax/lib/python3.8/site-packages/ChimeraX_main.py", line 712, in init run(sess, cmd) File "/usr/lib/ucsf-chimerax/lib/python3.8/site-packages/chimerax/core/commands/run.py", line 36, in run results = command.run(text, log=log, return_json=return_json) File "/usr/lib/ucsf-chimerax/lib/python3.8/site-packages/chimerax/core/commands/cli.py", line 2852, in run result = ci.function(session, **kw_args) File "/usr/lib/ucsf-chimerax/lib/python3.8/site-packages/chimerax/addh/cmd.py", line 63, in cmd_addh add_h_func(session, structures, template=template, in_isolation=in_isolation, **prot_schemes) File "/usr/lib/ucsf-chimerax/lib/python3.8/site-packages/chimerax/addh/cmd.py", line 170, in hbond_add_hydrogens add_hydrogens(session, atoms, type_info_for_atom, naming_schemas, hydrogen_totals, File "/usr/lib/ucsf-chimerax/lib/python3.8/site-packages/chimerax/addh/hbond.py", line 214, in add_hydrogens _attach_hydrogens(atom, altloc_hpos_info, bonding_info) File "/usr/lib/ucsf-chimerax/lib/python3.8/site-packages/chimerax/addh/hbond.py", line 895, in _attach_hydrogens add_altloc_hyds(atom, altloc_hpos_info, invert, bonding_info, total_hydrogens, naming_schema) File "/usr/lib/ucsf-chimerax/lib/python3.8/site-packages/chimerax/addh/cmd.py", line 862, in add_altloc_hyds h = new_hydrogen(atom, i+1, total_hydrogens, naming_schema, File "/usr/lib/ucsf-chimerax/lib/python3.8/site-packages/chimerax/addh/cmd.py", line 882, in new_hydrogen metal_pos = metal.get_alt_loc_coord(alt_loc) File "atomic_cpp/cymol.pyx", line 587, in chimerax.atomic.cymol.CyAtom.get_alt_loc_coord ValueError: Atom /A MG 702 MG has no alt loc B I'm using ucsf-chimerax_1.2.5-1_amd64.deb installed on Ubuntu 20.04. I've done some digging, and I cannot figure out what is going on. Any help would be appreciated. Thanks in advance! -James -- James Loy, Ph. D. 614.915.9792 LinkedIn <https://www.linkedin.com/in/james-m-loy-ph-d-ba2256a/>

3 4

The PDB code for the demo picture on the website
by BAOCHENG LIU 28 Jul '21

28 Jul '21

Hi chimerax group, I am a postdoc in UCLA using chimerax. Thanks for providing all scientists this powerful software that makes life easier. I have a question here when I was learning the cartoon/ribbon style command line. So, I saw the 4 demo pictures on the website https://www.rbvi.ucsf.edu/chimerax/docs/user/commands/cartoon.html#style and just realized the structure just looks similar to one of my structures. Could you please tell me the PDB code for that structure so I can compare it with mine in detail? Hope it is released. Thank you. Best regards, Baocheng

2 1

resfit command for nuclei acid
by Wen-Jin Winston Wu 27 Jul '21

27 Jul '21

Hi Tom, I have just tried to use the "resfit" command ChimeraX Does the nice command of "resfit" in ChimeraX support inspection on nuclei acid? It seems that it only support protein residues as with the command " resfit #1/D:DT map #3", it returned with the message that "None of the 9 specified residues have backbone atoms N, CA and C". I have not checked out the daily build version yet, but thought that I can ask first. Thanks, Best wishes, Winston

2 2

Custom colour for atoms with bfactor==0
by Lorena Zuzic 27 Jul '21

27 Jul '21

Hi, I wanted to know if there is a way of colouring my structure by bfactor, but with an additional condition where all bfactor==0 atoms are coloured in grey. Currently, I am using a white to red gradient for my B-factors: color bfactor range -2.2, 2.2 In this case, bfactor==0 values are coloured white. However, I would like them to be grey and outside the gradient (as they represent an unmapped portion of the protein). Thanks! Lorena

2 2

create mask from "shapes"
by Roberto Marabini 27 Jul '21

27 Jul '21

Hi, It is possible to create a mask from a shape?. For example from the result of "*shape icosahedron".* If the command does not exist I guess I may create it as follows * the input would be the 3D map to be masked and the shape to be used as mask * request all the (varray, tarray) from the shape. * from varray,tarray build the triangles that define the surface of the shape * for each triangle create the normal vector * multiply each normal vector by the position of each voxel (dot product) * keep those voxels that have negative dot products for all the triangles. thanks for the help

2 2

Automated Fitting of models into maps and saving fits with a correlation score > X
by Vorländer,Matthias Kopano 26 Jul '21

26 Jul '21

Dear all, I have a set of 100 “artificial” tomograms, each containing approx 100 copies of a simulated density map of my protein of interest. I would like to fit each tomogram with the PDB of my POI, and save copies for all fits with a correlation score > 90%. Using the fitmap command in Chimera and then manually selecting the fits that meet the criterium works, but takes quiet a long time for a larger amount of data. I wonder if this could be automated, and if somehow would be able me to put together a script (is it possible to execute such tasks in a non-gui way, by submitting it to a cluster so that it could be parallelized?). Thanks a lot in advance, Best, Matthias

2 2

unexpected behavior of build start
by Alexis Rohou 26 Jul '21

26 Jul '21

Hi ChimeraX team, I'm running into unexpected behavior when using the build tool. Here's what I'm doing: - open map --> model #1 - open PDB --> model #2 - fit #2 in #1 (the PDB moves by ~20 Å at this step) - cofr centerOfView showPivot true - move the view around so that the pivot axes intersect where I want to place a new atom - build start atom #2 expected result: a new H atom is created exactly at the center of view (where the pivot axes intersect) actual result: the new H atom is created some distance away; I think the vector from where the new H atom is built to the cofr is the same vector as the PDB model was displaced by the fitting into the map (my second step, above), but I haven't checked that carefully. Is this what is expected? It confused me :) Is there a command I can use to move the atom to the correct location after it's been created? Interestingly, if I add a H atom into a new model, then it appears where I expect it, at the cofr: - build start atom "custom built" This is with 1.2.5 (2021-05-24) Cheers, Alexis

2 2

question
by 王镐锋 26 Jul '21

26 Jul '21

Dear guys, Sorry to disturb you guys. When I use the UCSF ChimeraX, I try to define the second structure for part of model. I type the command like "dssp (#1 & sel) energy cutoff 0.5 minheliexlen 3", it works for the whole model instead of what I choose specially. Could you please help me? Thanks so much! Best, Haofeng Wang Ph.D student Tianjin University, China

2 3

measure volume in ChimeraX
by Andrew Blyth 24 Jul '21

24 Jul '21

Hi, I am having trouble getting the ‘measure volume’ and ‘measure area’ command to work in chimera. I have been trying the command: measure volume #3/A:457 for the structure that I have been using, however, nothing happens when I execute this command. Could you please provide me with an example command that will work for measuring the volume or area of a residue? Thanks, Andrew Blyth PhD Candidate Medical Biochemistry - Flinders University Room 6E109 Flinders Medical Centre | South Australia 5001, Australia Phone: +61 8 8204 5098 | E: andrew.blyth(a)flinders.edu.au<mailto:andrew.blyth@flinders.edu.au>

2 1

Model missing residues in Chimera X
by He, Amy 23 Jul '21

23 Jul '21

Dear Chimera X community, I’m a new user of Chimera X and I have a question about the built-in Modeller function in Chimera X Previously in Chimera 2, we use the “Model/Refine Loop” function to model missing residues in the experimental structure, before any further calculation or simulations. The “Model/Refine Loop” function uses Modeller and the function provides modeled, complete structures in which the non-missing residues do not move. In Chimera X, a similar function is “Modeller Comparative” but it works differently. The “Modeller Comparative” performs a modeling for the full structure with the given sequence. Is possible in Chimera X to model the missing residues, without moving the existent residues? Thank you for your kind advice in advance! Thanks, Amy -- Amy He Chemistry Graduate Teaching Assistant Hadad Research Group Ohio State University he.1768(a)osu.edu<mailto:he.1768@osu.edu>

2 2

How to access ChimeraX remotely from macbook (OS mojave)?
by Rayees Mattoo 22 Jul '21

22 Jul '21

Hi, I am trying to access ChimeraX remotley using my mac book pro. The ChimeraX is installed on linux machine. Upon launching, the chimeraX GUI appears and suddenly disappears with the following error message: "ChimeraX requires OpenGL graphics version 3.3. Your computer graphics driver provided version 1.4, Try updating your graphics driver". My mac currently has macOS mojave version 10.14.6 and it seems it does not have OpenGL graphics version 3.3 required to display chimeraX remotely. Is there any way out to fix the problem? Not sure if updating my macbook to Catalina or BigSur is going to help! Best Rayees

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Re: [chimerax-users] How to access ChimeraX remotely from macbook (OS mojave)?
by Tom Goddard 22 Jul '21

22 Jul '21

Hi Rayees, Mac Air graphics is pretty slow for running ISOLDE. But Tristan Croll who develops ISOLDE added a nice option "Sim Fidelity" to the ISOLDE panel in the middle -- by default it is set to "High" and setting it to "Quick" will make the simulations run much faster. Here is what Tristan told me about what it does: "The latest ISOLDE release has new “sim fidelity” radio buttons on the “Sim settings” tab. The “quick” mode (no implicit solvent, nonbonded cutoff tightened to 9 Å) runs about 4x faster on my MacBook Air and still gives reasonable results in good density. Still not *fast*, but I think definitely usable." This is in ISOLDE 1.2.2. If you need to update ISOLDE use ChimeraX menu Tools / More Tools.... If this is still too slow, I'm afraid it is a limitation. You have to use faster hardware. The realtime dynamics simulations used by ISOLDE need fast graphics - the molecular dynamics is done with OpenMM using OpenCL or CUDA GPU accelerated computation. CUDA is fastest and needs Nvidia graphics and the CUDA driver installed -- Macs don't support Nvidia gpus. The macOS OpenCL implementation is very slow, almost as slow as just running on the CPU. Tristan has ISOLDE benchmarks on different hardware here https://isolde.cimr.cam.ac.uk/performance-benchmarks/ Tom > On Jul 22, 2021, at 6:03 PM, Rayees Mattoo <rmattoo(a)stanford.edu> wrote: > > Hi Tom, > Thanks for responding. Actually, I wanted to run ISOLDE from chimeraX and already tried it running on Mac with my 500KDa protein complex. It was very slow, wanted to try on linux machine and ran into the OpenGL problem. Do you have any suggestions how to run ISOLDE faster on mac? > > Best > Rayees > From: Tom Goddard <goddard(a)sonic.net> > Sent: Thursday, July 22, 2021 5:32 PM > To: Rayees Mattoo <rmattoo(a)stanford.edu> > Cc: chimerax-users(a)cgl.ucsf.edu <chimerax-users(a)cgl.ucsf.edu>; chimerax-bugs(a)cgl.ucsf.edu <chimerax-bugs(a)cgl.ucsf.edu> > Subject: Re: [chimerax-users] How to access ChimeraX remotely from macbook (OS mojave)? > > Hi Rayees, > > I guess you have X Windows (XQuartz) running on your Mac and are hoping that X remote display from Linux to the Mac will work with ChimeraX. Unfortunately X Windows remote display of 3D OpenGL graphics has not worked reliably since the days Silicon Graphics computers in the 1990s. It is possible to get it to work between two Linux machines with identical OpenGL drivers. But it would be a near miracle if the XQuartz implementation of X Windows on Mac could handle the OpenGL from a Linux machine. > > The sensible approach is to run ChimeraX directly on your MacBook Pro. We don't recommend remote display even when it works because rendering speed is likely to be poor. > > Tom > > >> On Jul 22, 2021, at 1:31 PM, Rayees Mattoo via ChimeraX-users <chimerax-users(a)cgl.ucsf.edu <mailto:chimerax-users@cgl.ucsf.edu>> wrote: >> >> Hi, >> I am trying to access ChimeraX remotley using my mac book pro. The ChimeraX is installed on linux machine. Upon launching, the chimeraX GUI appears and suddenly disappears with the following error message: "ChimeraX requires OpenGL graphics version 3.3. Your computer graphics driver provided version 1.4, Try updating your graphics driver". >> My mac currently has macOS mojave version 10.14.6 and it seems it does not have OpenGL graphics version 3.3 required to display chimeraX remotely. Is there any way out to fix the problem? Not sure if updating my macbook to Catalina or BigSur is going to help! >> >> Best >> Rayees >> >> >> _______________________________________________ >> ChimeraX-users mailing list >> ChimeraX-users(a)cgl.ucsf.edu <mailto:ChimeraX-users@cgl.ucsf.edu> >> Manage subscription: >> https://www.rbvi.ucsf.edu/mailman/listinfo/chimerax-users <https://www.rbvi.ucsf.edu/mailman/listinfo/chimerax-users>

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Re: [chimerax-users] python loop with ChimeraX
by Rangarajan, Amith 21 Jul '21

21 Jul '21

Hi, I am new to chimeraX , i want to loop through a set of biological assemblies measuring SASA of selecting residues and write them to a file. I need some help with starting on this .How to include this into the .cxc script? is there a example somewhere? please share your tips and suggestions, thanks everyone ! warm regards, Amith

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