- ChimeraX-users - RBVI Mailing Lists

Re: cartoon not displaying in ChimeraX despite complete backbone
by amith ranga 22 Apr '25

22 Apr '25

Dear ChimeraX users, I'm unable to display the cartoon representation for pdb file in ChimeraX, even though the residues and atoms appear complete. The structure contains standard RNA residues (A, G, U) , Each residue includes all expected backbone atoms (P, O5', C5', C4', C3', O3', C1', O4', etc.) as well as complete base atoms and hydrogens. The file was written out from MOE software and I am not sure if this is an issue. Some tips on how to edit the pdb file would be helpful Thanks, amith

4 3

[ISOLDE] Handling Lys-Asp iso-peptide bonds and D-amino acids
by Yang Lee 22 Apr '25

22 Apr '25

Addressing this to Tristan, in all likelihood. Is there a way of parameterising KD isopeptide bonds and D-amino acids? Perhaps a secret three letter code I can rename the residues to make them play nice? Unfortunately, I'm trying to model a peptide that has both of these exotic elements. Cheers, Yang

3 15

Color of unrolled density maps
by Sen, Anindito 21 Apr '25

21 Apr '25

Dear ChimeraX Team, Is there a way we can keep/restore the color of the unrolled helical density maps ? Regards Anindito Sen. Ph.D Microscopy and Imaging Center Texas A&M University 301 Old Main Dr College Station, TX 77843-2257 Office: ILSB Room 1133 <http://microscopy.tamu.edu/>Tel. 979-458-9881 fax: 979-847-8933 http://microscopy.tamu.edu<http://microscopy.tamu.edu/>

2 1

Re: Regarding peptide bond formation using chimeraX
by Tom Goddard 21 Apr '25

21 Apr '25

Hi Harpreet, I'm not sure how you deleted the bond. If you deleted a peptide bond with delete bonds /A:102@C /A:103@N or the equivalent menu Actions / Atoms and Bonds / delete then you could just recreate it with bond /A:102@C /A:103@N I'm not sure why you would do that since there is no need to delete a bond to move the two pieces of the structure. Instead maybe you split the protein into two separate models. In that case you can't simply add a bond between different models, instead you have to combine the models (e.g. command "combine #1,2"). You might get better answers on the ChimeraX mailing list, so I have CC'ed that list. Tom > On Apr 21, 2025, at 4:06 PM, Singh, Harpreet <harpreet.singh2(a)ucsf.edu> wrote: > > Dear Professor Goddard, > > I hope you are doing well. > > I am a Postdoctoral scholar from the Robert M. Stroud lab. I recently deleted a peptide bond from our protein structure to adjust the model for cryo-electron microscopy (cryo-EM) mapping. I am now attempting to reconstruct the peptide bond using the Build Structure tool. However, I am encountering an error message indicating that there are no chain-terminal carbons in the atoms. > > I would appreciate your assistance in resolving this issue. > > Thank you for your time and consideration. > > Best regards, > Harpreet Singh > Postdoctoral Fellow, Stroud lab > Department of Biochemistry and Biophysics > UCSF

1 0

Color of unrolled density maps
by Eric Pettersen 21 Apr '25

21 Apr '25

The original was sent to the wrong address (chimerax-users-bounces)… Dear ChimeraX Team, Is there a way we can keep/restore the color of the unrolled helical density maps ? Regards Anindito Sen. Ph.D Microscopy and Imaging Center Texas A&M University 301 Old Main Dr College Station, TX 77843-2257 Office: ILSB Room 1133 <http://microscopy.tamu.edu/>Tel. 979-458-9881 fax: 979-847-8933 http://microscopy.tamu.edu <http://microscopy.tamu.edu/>

1 0

Quality of sphere representation
by Enrico Martinez 21 Apr '25

21 Apr '25

Dear ChimeraX users! I wonder if there is a special option which would allow me to increase the quality of sphere representation (which are displayed by default for big cryo-em protein complexes loaded in chimeraX) in the same way as it can be done for surfaces using gridSpacing ? Many thanks in advance Enrico

2 1

Concatenating trajectories in ChimeraX
by Alexandra Zahradnikova 20 Apr '25

20 Apr '25

Dear All, I am new in molecular simulation and not very much experienced with ChimeraX. I did not find an easy way to concatenate trajectories (in my case, .xtc files from gromacs). Any suggestions would be welcome. Thanks in advance Sasha ________________________________________________________________________ Alexandra Zahradníková, PhD Department of Cell Cardiology Institute of Experimental Endocrinology Biomedical Research Centre SAS Dúbravská cesta 9 845 05 Bratislava Slovakia Mobile: +421 908 069 796

4 4

seeking help
by 张可依 20 Apr '25

20 Apr '25

Dear chimerax, hello, I would like to know if chimerax can draw protein secondary structure topology maps, and if so, can you tell me how to do the drawing?Something like the picture below Your help is of great importance to me and I, with my most sincere hope, look forward to your reply. All the best keyi [cid:494273c0-4f59-4f19-bd4d-5ac989d92136]

2 1

Question about morphing trajectory
by Enrico Martinez 20 Apr '25

20 Apr '25

Dear ChimeraX users ! Using the following command, I generated a 200-frame trajectory that morphs through three selected conformations: morph #2,3,4 core 0.1 frames 200 wrap f rate linear Would it be possible to have the morphing trajectory end on the starting structure (so the full transition path ends on the first snapshot in the morphin trajectory), so that I can create a smoothly looped GIF animation? Many thanks in advance ! Enrico

2 3

Combine PDBs in models instead of changing chainId ?
by Vincent CHAPTAL 18 Apr '25

18 Apr '25

Hi, using "combine #1-3" with 3 models having chain A only, it changes the chain Id to B and C for models #2-3, as described in the doc. Is it possible to combine PDBs as a multimodel PDB, seperated by MODEL keywords in the PDB file? Thank you. Vincent -- Vincent Chaptal, PhD Director of GdR APPICOM Drug Resistance and Membrane Proteins Lab MMSB -UMR5086 7 passage du Vercors 69007 LYON FRANCE +33 4 37 65 29 01 http://www.appicom.cnrs.fr http://mmsb.cnrs.fr/en/

2 2

Request for Academic Use Confirmation Document – ChimeraX Demonstration Class
by Coordenação Farmácia_ 17 Apr '25

17 Apr '25

Dear UCSF ChimeraX Team, My name is Emanuell Santos, I am a pharmacist, Ph.D. in Drug Development Technology, and the coordinator of the Pharmacy program at a private Brazilian college. I also teach Medicinal Chemistry for both Pharmacy and Medical students. I am reaching out to respectfully request your support in including UCSF ChimeraX in a practical session of my Medicinal Chemistry course. The goal is to introduce students to molecular modeling approaches through a demonstrative class where they can also explore some of the software’s functionalities directly. This initiative is aligned with national educational guidelines from our Ministry of Education, which emphasize the inclusion of innovative and technological methodologies in undergraduate teaching. I plan to use the free academic version of ChimeraX solely for educational purposes and without any commercial intent. I kindly ask whether it would be possible to obtain a brief statement or document from UCSF (even if generic) confirming that such use falls within the allowed academic scope. This would be helpful in documenting compliance with institutional and governmental regulations. I greatly appreciate your attention and support, and I look forward to your response. Warm regards, Emanuell Santos Coordinator – Pharmacy Program FACENE/RN -- Prof. Dr. Emanuell dos Santos Silva *Coordenação de Farmácia - FACENE/RN* Por favor, confirmar o recebimento deste e-mail.

2 2

Re: Unable to display GLY in Chimera
by Elaine Meng 15 Apr '25

15 Apr '25

Hello Qiang, I guess you are talking about ChimeraX, not Chimera. They are two different programs. You can just hide all the other glycine atoms. This is not a bug. The suppressBackboneDisplay *allows* you to show both cartoon and backbone atoms at the same time, but you can still hide all the atoms you don't want to show. cartoon suppress false hide :gly show :93 I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Resource for Biocomputing, Visualization, and Informatics Department of Pharmaceutical Chemistry University of California, San Francisco > On Apr 15, 2025, at 9:16 AM, Qiang Liu <liu01301(a)umn.edu> wrote: > > Hi Chimera > > I am a Chimera user and unable to display single GLY as stick and cartoon. I found commend "suppressBackboneDisplay", however this command makes all the GLYs displayed as stick and cartoon. I only want to display GLY93 as stick and cartoon and could you please let me know how to make it happen? Thank you. > > Qiang. > > -- > Qiang Liu, Aldrich Lab > Medicinal Chemistry, College of Pharmacy > University of Minnesota > > 8-115 Weaver-Densford Hall > 308 Harvard St SE > Minneapolis, MN 55455

1 0

How to save the PAE plot as an image in ChimeraX using command line ?
by picasa1983＠gmail.com 14 Apr '25

14 Apr '25

Hi, I am using ChimeraX to visualize AlphaFold models and display the PAE plot with: alphafold pae #1 /path/to/confidences.json I would like to save only the PAE plot (not the 3D structure view) as a .png or .pdf file. What is the correct command to save the PAE plot image in ChimeraX? Thanks a lot!

4 5

B-strand arrowheads
by Lee Bardwell 13 Apr '25

13 Apr '25

Hi Elaine and team, I’ve noticed an issue that sometimes happens when I change some residues to a beta strand, e.g. setattr /A:149-151 res ss_type 1. Sometimes an arrowhead is not placed at the end of the strand. Am I doing something wrong? Or is there a way to force an arrowhead? Thank you! _________________________________ Lee Bardwell, Ph.D. Professor and Vice-Chair, Dept. of Developmental & Cell Biology Charlie Dunlop School of Biological Sciences University of California, Irvine __________________________________

2 1

Removing distance label from distance monitor
by Elaine Meng 13 Apr '25

13 Apr '25

> On Apr 12, 2025, at 2:01 AM, Yu GUO 郭宇 <guoyu60(a)westlake.edu.cn> wrote: > > Dear UCSF Chimera(X) team, > > I am using ChimeraX 1.9. As shown in the picture below, I labelled the atomic distance 1.52 A. I want to retain the dashed line but to remove the number "1.52". How can I realize this? > > Thank you! Next time, please send your questions to chimerax-users(a)cgl.ucsf.edu <mailto:chimerax-users@cgl.ucsf.edu> (CC'd here) --- if you send it to me only it may not get answered. I changed the subject line to describe the current topic. If you have distance monitors displayed there are several ways to hide the number labels. One way is command ~label pseudobonds If you just wanted to draw dashed lines and not show any distances, it may be a waste of time to use the "distance" command or Distances tool. Instead you can just use command "pbond" available in ChimeraX 1.8 or later, see <https://rbvi.ucsf.edu/chimerax/docs/user/commands/pbond.html> I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Resource for Biocomputing, Visualization, and Informatics Department of Pharmaceutical Chemistry University of California, San Francisco

1 0

SwissDock dock4 in ChimeraX not recognized
by Nadia Elghobashi-Meinhardt 12 Apr '25

12 Apr '25

Dear all, When I try to open a SwissDock .dock4 file in ChimeraX, the swissdock format is not recognized. The chimeraX forum advises using "format swissdock" when opening the file, but I am getting 'invalid "format" argument'. Does anybody have a solution to this problem? Many thanks, Nadia -- Dr. Nadia Elghobashi-Meinhardt <https://people.ucd.ie/nadia.elghobashi-meinhardt> Assistant Professor (Ad Astra Fellow) School of Chemistry University College Dublin Belfield, Dublin 4, Ireland Tel: +353 1 716 2044

2 2

Features of Chimera X
by Ogbuehi, Ulochukwu 09 Apr '25

09 Apr '25

Greetings, I had a couple questions about the usability of ChimeraX. 1. Is there a way I can insert a variant sequence, and it produce the structure that I would like modelled. Or would I have to strictly use a generated PDB file of my variant for ChimeraX to model the structure. 1. I was able to upload and model my WT protein structure in ChimeraX from the AlphaFold WT PDB file I downloaded; however, I am not able to generate a PDB file for my variants and would like to know if there is a feature that allows me to insert my aa sequence into ChimeraX to model the variant structure? Or maybe even a feature that allows you to generate a PDB file using an aa sequence. 1. Would I need the WT PDB file to be uploaded and modelled in ChimeraX first prior to adding in my aa sequence, granted that I am even able to insert an aa sequence directly into ChimeraX? Kindest Regards, Bethel Ogbuehi

2 1

Refinement in ISOLDE failing
by Firdous Tarique 09 Apr '25

09 Apr '25

Dear everyone I am trying to refine my protein using ISOLDE in ChimeraX which is failing with the following error. "At least one residue in your model does not match any templates in the MD forcefield. This may be due to missing or superfluous atoms, or an unusual residue that has not yet been parameterised. Launching the unparameterised residue widget to help sort this out." The protein contains two heme molecules and Ca ions which obviously is the reason why it is failing. Once these molecules are deleted it runs fine. My question is how to add that specific MD force field for these molecules in order to run the ISOLDE in ChimeraX. Any input would be appreciated. Firdous

1 1

Re: issues with writing models as pdb files
by arangarajan＠initialtx.com 08 Apr '25

08 Apr '25

Hi everyone, I noticed that sometimes when i write pdb of one model or a selection , it does not open in other programs.( MOE,Pymol). One of the errors i noticed recently was that th pdb file was written as a multi model pdb file ( each of the 70 residues in the protein were separate models) , i cleaned it using notepad++ by removing the model lines and it was opening correctly. i was told that it might be related to using split command. i use split often and it might be the case. can some one please explain how using split can lead to this? and if so what is best way to fix it? should i perhaps run some version of combine command on the model prior to writing it out as pdb file. thanks again, best amith

3 4

Can't open ChimeraX on my Win11
by kangkang042＠126.com 07 Apr '25

07 Apr '25

About 2 weeks ago, it worked fine. Today when I click the ChimeraX startup, nothing happened. I reinstalled the lastest version v1.9, nothing changed. Run ChimeraX-console.exe in cmd, it shows these information: NOTE: Traceback (most recent call last): File "<frozen runpy>", line 198, in _run_module_as_main File "<frozen runpy>", line 88, in _run_code File "E:\chimeraX\installation\bin\Lib\site- packages\chimerax\core\\__main__.py", line 1217, in <module> exit_code = init(sys.argv) ^^^^^^^^^^^^^^ File "E:\chimeraX\installation\bin\Lib\site- packages\chimerax\core\\__main__.py", line 653, in init sess = session.Session( ^^^^^^^^^^^^^^^^ File "E:\chimeraX\installation\bin\Lib\site- packages\chimerax\core\session.py", line 551, in __init__ from chimerax.graphics.gsession import register_graphics_session_save File "E:\chimeraX\installation\bin\Lib\site- packages\chimerax\graphics\\__init__.py", line 37, in <module> import chimerax.arrays File "E:\chimeraX\installation\bin\Lib\site- packages\chimerax\arrays\\__init__.py", line 24, in <module> from ._pyarrays import get_lib, get_include, load_libarrays File "E:\chimeraX\installation\bin\Lib\site- packages\chimerax\arrays\\_pyarrays.py", line 40, in <module> from . import _arrays ImportError: DLL load failed while importing _arrays: 找不到指定的模块。 BUG: ImportError: DLL load failed while importing _arrays: 找不到指定的模块。 File "E:\chimeraX\installation\bin\Lib\site- packages\chimerax\arrays\\_pyarrays.py", line 40, in from . import _arrays _See log for complete Python traceback._ My PC: Win11 Pro Workstation 26100.3624

2 3

How to browse inspect ligands?
by Guillaume Gaullier 04 Apr '25

04 Apr '25

Hello ChimeraX team, These days I look a lot a structures of photosystems, which contain large numbers of ligands: chlorophylls, carotenoids, etc. each by the dozens, adding up easily to more than 100 ligands. Is there any tool to browse through all ligands systematically? Ideally something similar to the sequence viewer, but for ligands. Or a way to generate a list with chain IDs and "residue" numbers reported, and clicking rows in the list would select the corresponding ligand. I looked for something like this, but couldn't find anything. Thank you in advance, Guillaume När du har kontakt med oss på Uppsala universitet med e-post så innebär det att vi behandlar dina personuppgifter. För att läsa mer om hur vi gör det kan du läsa här: http://www.uu.se/om-uu/dataskydd-personuppgifter/ E-mailing Uppsala University means that we will process your personal data. For more information on how this is performed, please read here: http://www.uu.se/en/about-uu/data-protection-policy

4 5

saving cloned structures on chimerax inquiry
by Joel Gallardo 03 Apr '25

03 Apr '25

to whom it may concern, i have mapped out a mol2file onto a structure found in a .mrc file. and then i ran this command to multiply the mol2 structure: sym #2 h,0.357979,132.83196,72,-40 coord #1 center 119.04,119.04,119.04 it multiplied it as intended which is good but now i want to save those multiplied mol2 files into a sperate mol2 files. i tried this command: save multiplied_structures.mol2 format mol2 models #2 but this only saves a single mol2 structure into the new mol2 file. i want all 72 molecules in one mol2 file. can you give me some advice as to how i may be able to do this? my ultimate goal is to take that mol2 file and do an md simulation. Best, Joel Gallardo (Graduate student in chemistry)

2 3

Keeping track of H-bonds in trajectories
by Alexandra Zahradnikova 02 Apr '25

02 Apr '25

Hello, I am new in molecular simulation and not very much experienced with ChimeraX. Is there a way to keep track of H-bonds between two specific residues (they can form one or more H-bonds) during the course of the trajectories (in my case, .xtc files from gromacs)? Thanks in advance Sasha ________________________________________________________________________ Alexandra Zahradníková, PhD Department of Cell Cardiology Institute of Experimental Endocrinology Biomedical Research Centre SAS Dúbravská cesta 9 845 05 Bratislava Slovakia Mobile: +421 908 069 796

2 2

Create new attributes
by javisanchezdelrio＠gmail.com 31 Mar '25

31 Mar '25

Hello! I am trying to create a new attribute in a cif file called align_rmsd. For the example, assume I want all atoms to have this attribute equal to 5. For this, I am opening the file in ChimeraX and applying the following command: setattr atoms align_rmsd 5.0 create true type float With the following result: Assigning align_rmsd attribute to 145 items However, when I do "save new.cif" I don't see any new attribute in the loop _atom_site.align_rmsd nor any value equal to 5. How can I store this values in a new cif file so that I see the values equal to 5? Thank you in advance! Javier

3 2

Downloading ISOLDE
by Ashley Gutierrez 28 Mar '25

28 Mar '25

Hi there, I am having a bit trouble downloading the ISOLDE bundle. While I can download the .whl to my computer, it will not open in ChimeraX. Please let me know if I am missing some commands in between, I am new to this system. Thank you (:

2 1