- ChimeraX-users - RBVI Mailing Lists

Inquiry to docking protein onto lipid bilayer
by Tommy Tong 12 Mar '25

12 Mar '25

Dear ChimeraX experts, Good afternoon. My name is Tommy from San Diego Biomed. I am a beginner to ChimeraX version 1.9. May I ask if it is possible to use ChimeraX to dock a membrane protein into a lipid bilayer? I obtained Phosphotidylcholine bilayer (POPC) structure from CHARMM-GUI webpage https://charmm-gui.org/?doc=archive&lib=lipid_pure, and was wondering if it is possible to “place” a protein into this POPC structure in ChimeraX. Your help and advice on this is greatly appreciated. Thank you. Sincerely, Tommy

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Obtain individual RMSD values
by javisanchezdelrio＠gmail.com 12 Mar '25

12 Mar '25

Hello, I have an issue when applying matchmaker command in ChimeraX. When I execute the command: matchmaker #1 to #2 showAlignment true I obtain the alignment with the bars in the upper layer showing the individual RMSD of each residue. But the results yields the overall RMSD of the alignment (i.e. RMSD between 108 pruned atoms). Is there any way to obtain those individual RMSDs of the alignment as a file or have them printed in the log for post-processing? Thank you in advance

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Dividing a huge model (& map) into smaller chunks
by Alejandro Buschiazzo 12 Mar '25

12 Mar '25

Dear chimeraX developers/users Using version 1.9, I am trying to divide a very big mmcif model (230K + nonH atoms; >130 chains) and corresponding mrc map, into a number of smaller mmcif files (and corresponding cropped maps, covering just those parts). What I’ve tried so far unsuccessfully: I can create dummy atoms with build start atom, at desired x,y,z points, so that I can then use select zone to select a radius and keep parts near each dummy atom. Yet, that is suboptimal: I would largely prefer to keep (build) boxes, and not spheres, ensuring complete recovery and no blind spots. So that each box slightly overlaps with the neighboring one, and systematically covers the whole original map volume. 1. How can I generate a script that will do this "systematic windowing” screening, making boxes of a defined side-length at each step, and keeping the model within? 2. How should I then crop the original map, so that it covers each box (with a small padding on the borders)? 3. How should I stitch back the models, so that I don’t loose any atomic coordinates information? (of course that stitching will be done after I do some refinement work on each boxed model vs map) So sorry for the many questions! I’ve been trying hard to find this kind of strategy, and just can’t seem to succeed…. Thank you very much in advance Alejandro -- Alejandro Buschiazzo, PhD Associate Professor Laboratory of Molecular & Structural Microbiology Institut Pasteur de Montevideo Mataojo 2020 Montevideo 11400 URUGUAY Phone: +598 25220910 ext. 120 Fax: +598 25224185 https://pasteur.uy/en/laboratories/molecular-and-structural-microbiology/

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General ?s - Foldseek (Sequence Plot) and Similar Structures Table
by Emir MALOVIC 11 Mar '25

11 Mar '25

Hello, Quick question: When I load the sequence plot, I receive 2 sequence images separated by a very large black space. When I save the image as a PNG, the black space between the sequence images is retained. Basically, the image is mostly black space. Is there a way to change that or is this a bug? Am I able to somehow copy the Similar Structures table or export it into Excel? A copy/paste function would be ideal and quick. I am using the Chimera 1.10 dev. Please let me know at your earliest convenience! Thank you, Emir

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Suggestion for improvement
by James Raymond 11 Mar '25

11 Mar '25

I love ChimeraX and use it often for my work, e.g. this one <https://www.pnas.org/doi/10.1073/pnas.2421910122>. When using AlphaFold to predict protein structure, the sequence is pasted into the sequence box. It does not allow entering the fasta name ">name" before the sequence.. Allowing a name to be included can avoid much confusion. Presently, the screen shows the output as "best_model" which becomes very confusing when several best models are shown on the screen. James Raymond Univ. Nevada Las Vegas

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What is the .exe file for ChimeraX Toolbox?
by m.i.bashir＠bham.ac.uk 11 Mar '25

11 Mar '25

Hi all, First time posting here. I'm looking to find the name and location of the file/folder that manages the ChimeraX in-app browser. The way I launch the browser is to go to 'tools' in the top bar, then press 'more tools', and then it brings up the ChimeraX Toolshed Where is the .exe file that controls this in app browser? I am attempting to find the .exe file and black list it, so we can use ChimeraX for an exam Thanks,

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SASA in MDS
by Gabriel López Velázquez 10 Mar '25

10 Mar '25

Dear Elaine, I am sorry; I did not state the subject of my previous email. I would ask for help. How can I calculate SASA as a function of time from the MD simulations in Chimerax? What archives need to perform it? Thanks in advance! Gabriel.

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(no subject)
by Gabriel López Velázquez 10 Mar '25

10 Mar '25

Dear Elaine, I would ask for help. How can I calculate SASA as a function of time from the MD simulations in Chimerax? What archives need to perform it? Thanks in advance! Gabriel.

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Inquiry About Favorable Contacts and Display Methods in ChimeraX
by 田畑　健士郎 07 Mar '25

07 Mar '25

Subject: Inquiry About Favorable Contacts and Display Methods in ChimeraX Dear ChimeraX Developers, My name is Kenshiro Tabata. I hope this email finds you well. I am currently using ChimeraX to analyze the effects of point mutations on protein structure, particularly in cases where a larger side chain (e.g., methionine) is replaced by a smaller one (e.g., valine). In such cases, I expect that interactions with the opposing amino acids may be reduced due to the decreased side-chain volume. To investigate this, I would like to ask for your guidance regarding the interpretation and visualization of favorable contacts. ________________________________ 1) Understanding Favorable Contacts I understand that the contacts command identifies all types of interactions, whereas the clashes command detects only unfavorable interactions. Based on this, I interpreted the positive VDW overlap as indicating unfavorable (repulsive) interactions, while an overlap between 0 and -0.4 represents favorable (attractive) interactions. Could you confirm if this understanding is correct? ________________________________ 2) Best Approach for Displaying Only Favorable Contacts To analyze how the mutation affects interactions, I would like to display only favorable contacts. Below is the approach I have considered: Proposed Approach 1. Retrieve all interactions (favorable, neutral, and unfavorable) using the contacts command contacts overlapCutoff -0.4 saveFile all_contacts.txt 2. Retrieve only neutral and unfavorable interactions contacts overlapCutoff 0 saveFile non_favorable_contacts.txt 3. Compute the difference between these two sets using Python, extract only favorable contacts, and format them into a ChimeraX pseudobond file # File paths all_contacts_path = "all_contacts.txt" non_favorable_contacts_path = "non_favorable_contacts.txt" favorable_contacts_path = "favorable_contacts.pb" # Read files with open(all_contacts_path, "r") as f: all_contacts = set(f.readlines()) with open(non_favorable_contacts_path, "r") as f: non_favorable_contacts = set(f.readlines()) # Extract favorable contacts favorable_contacts = all_contacts - non_favorable_contacts # Convert to ChimeraX pseudobond file format with open(favorable_contacts_path, "w") as f: f.write("; Pseudobond file for favorable contacts\n") f.write("; radius = 0.1\n; color = green\n; dashes = 6\n") for line in favorable_contacts: parts = line.strip().split() if len(parts) >= 4: atom1 = f"/{parts[0]}:{parts[1]}@{parts[2]}" atom2 = f"/{parts[3]}:{parts[4]}@{parts[5]}" f.write(f"{atom1} {atom2}\n") 4. Load the extracted favorable contacts into ChimeraX for visualization open favorable_contacts.pb Would this be an appropriate approach? Alternatively, is there a simpler or more precise way to achieve this in ChimeraX? I appreciate your time and assistance, and I look forward to your advice. Best regards, Kenshiro Tabata

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AI in ChimeraX
by Elaine Meng 07 Mar '25

07 Mar '25

On Mar 7, 2025, at 6:01 AM, Veach, Kevin G. <kevin.veach(a)uky.edu> wrote: > > Hi Elaine: > Does Chimera-X use Artificial Intelligence or Large Language Learning Models? > Thank you, > > Kevin > Kevin Veach, Computer Support Specialist II > University of Kentucky, Animal & Food Sciences Dept. Hi Kevin, Please use the chimerax-users(a)cgl.ucsf.edu <mailto:chimerax-users@cgl.ucsf.edu> address CC'd here for general questions about ChimeraX -- I'm not the top expert on all parts of ChimeraX, so you may get better answers from other developers or our user community. Regarding your question, my understanding is that ChimeraX itself does not use these kinds of calculations, but it has tools that interface to web services or other calculations (run outside of ChimeraX) that do use them. The ones that I can think of are AlphaFold/ColabFold and ESMFold: <https://rbvi.ucsf.edu/chimerax/docs/user/tools/alphafold.html> <https://rbvi.ucsf.edu/chimerax/docs/user/tools/alphafold.html#predict> <https://rbvi.ucsf.edu/chimerax/docs/user/tools/esmfold.html> <https://rbvi.ucsf.edu/chimerax/docs/user/tools/esmfold.html#predict> 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

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Creating movie in ChimeraX from YASARA simulation
by ibogdanov 07 Mar '25

07 Mar '25

Hi ! I have the following question - How can I create a movie, when I cannot use the YASARA.sce file from which I converted/extracted xtc.file(the trajectories) when I have all the snapshots(pdb and sim.files) created as separate files during the performed simulation in YASARA...I've uploaded for example the first pdb file of the series and the xtc.file but isn't the saved xtc.file(trajectories) of the whole simulation(for all the structures)? How would you suggest me to solve this problem, if ChimeraX doesn't support sce.files ? Thank you in advance! Kind Regards, Ivan Bogdanov

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Problem installing on OSX
by Thom Hughes 06 Mar '25

06 Mar '25

I apologize for the dumb question, but here it is. I want to install the isolde extension. When I go to more tools, isolde, and click the install button a .whl file downloads correctly. But then nothing happens. I’m running OSX 15.3.1. thanks in advance for any pointers!

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Unable to open the file after downloading ChimeraX
by Guo-Ping Zhou 05 Mar '25

05 Mar '25

Dear Sir/Madam, After downloading ChimeraX, I automatically get the attached .png in the application as a microsoft word file. However, I can't open the Quick Access Toolbar. Could you please tell me how to make it work? Thanks! Guo-Ping Zhou, Rocky Mount Life Sciences Institute, Rocky Mount, NC 27804

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(no subject)
by FRANGIE Christian 05 Mar '25

05 Mar '25

Dear UCSF ChimeraX Support Team, My name is Christian frangieh, I am currently using Chimera X to visualize my AlphaFold simulations, and I want to check when i introduce a mutation and change one residue (amino acid), whether there is a change in the surface accessibility of the residue. Currenlty i am checking this visually by checking whether the residue is exposed to the surface or hidden. Nevertheless, i would like to know how can i do this with a command or by some form of calculation or structural analysis. Can you please help me with this matter? Warm Regards, Christian

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Can not find Structure Minimization in ChimeraX menu
by N.B. Nugroho 04 Mar '25

04 Mar '25

Dear ChimeraX developers I a little bit confuse to find the Structure Minimization menu in ChimeraX. In Chimera 1.16 it located in menu Tools>Structure Editing>Minimize Structure. Could you please guide me for this little problem. Best regards Nuki B Nugroho

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(no subject)
by junjie han 02 Mar '25

02 Mar '25

Hi, I hope you are doing well. May I ask two questions? First one: Why does the connection part between the side chain and backbone, which is circled in a dashed line in ChimeraX, look so abnormal? How can I make it display normally? [cid:437c0c59-2e31-4251-ac9c-eff3f64af0dd] Second one: Is it possible to show the border only for a specific region of protein without hiding other regions? Thanks, Junjie

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define integer attributes for multiple individual pseudobonds
by hannes.ludewig＠googlemail.com 28 Feb '25

28 Feb '25

Dear developers, I am trying to color pseudobonds by an individual (per-bond) attribute value (integer). I seem to be unable to use .pb files to create individual pseudobonds. And when I am using the pbond command several times providing an individual name for each pseudobond thus creating individual models (#1.1, #1.2, etc) I am unable to assign an attribute and color all pseudobonds according to the corresponding attribute value. What I want to create is similar to the alphafold contacts colored by PAE. Only that the values I am providing aren't PAE and I would like to determine the residue pairs that form each pseudobond. I apologize in case I am overlooking something obvious, but your help and/or clarification would be very much appreciated. Thank you. Best wishes, Hannes

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Disulphide bridges in ISOLDE
by Guillaume Gaullier 28 Feb '25

28 Feb '25

Hello ISOLDE users and Tristan, Is there a distance threshold at which ISOLDE won't let me close a disulphide bridge? I am puzzled, because it seems I can close a disulphide between two Cys about 10 residues apart in sequence and quite far from each other in space. In fact much further apart than a bond length, so the resulting bond looks ridiculously stretched. But it is quickly fixed when running a local simulation, even if it needs to pull the backbone out of density to achieve a reasonable S-S bond length. In the same model, I have two other Cys that follow each other in sequence. When loading the AlphaFold prediction, the two S atoms are close enough (for some reason) that ISOLDE offers to make the disulphide, so I say yes. Later on, wanting to test both options to assess which one is best supported by the map, I can break this disulphide, but once I do there is no way to close it again. In this case, the two S atoms settle about 3.4 Å apart when removing the bond, which is longer than an ideal disulphide, but much shorter than the distance over which ISOLDE still allowed me to form a disulphide in the first case. The documentation doesn't say anything about disulphides (or somehow I missed it). In fact, there seems to be no command to operate on disulphides? Using the menu item does not write anything to the Log, so if there is a command I cannot find what it is and what options it might accept. If someone can help with this, I would appreciate it! Thank you, Guillaume --- Guillaume Gaullier, PhD Researcher, Blikstad group Molecular Biomimetics / Microbial Chemistry Department of Chemistry - Ångström Uppsala University Lägerhyddsvägen 1 752 37 Uppsala Sweden 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

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Assistance Required: Extracting List of Interacting Residues within 4 Å in UCSF Chimera
by Rashmi Aggarwal 27 Feb '25

27 Feb '25

Dear UCSF Chimera Support Team, I hope this message finds you well. I am currently working on analyzing interactions between two molecular structures using UCSF Chimera. I have successfully identified residues that are within a 4 Å distance between the two molecules. However, I am encountering difficulties in obtaining a clear, textual list of these interacting residues, as reading them directly from the visual representation is challenging. Could you please provide guidance on the specific commands or procedures within Chimera that would allow me to: 1. *Select residues* in one molecule that are within 4 Å of the other molecule. 2. *Generate and export a list* of these selected residues for further analysis. I have attempted various selection and reporting commands but have not yet achieved the desired outcome. Detailed instructions or references to relevant documentation would be greatly appreciated. Thank you very much for your assistance. Best regards, Rashmi

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Show side chain, main chain, and cartoon at the same time
by Zhang, Miao 27 Feb '25

27 Feb '25

Dear colleagues I am new to ChimeraX. I am trying to figure out how to show side chain, main chain, and cartoon at the same time in a protein structure. Like the one below made in other software. Could you please help? [cid:image001.png@01D9D154.CE3D4440] Best, - - - - - - - - - - - - - - - - - Miao Zhang Ph.D. Associate Professor Chapman University School of Pharmacy 9401 Jeronimo Rd, Suite 297W Irvine, CA 92618 Phone: 714-516-5478 http://www.chapman.edu/our-faculty/miao-zhang

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Cannot click popup windows in ChimeraX WSL installation
by Jobichen 26 Feb '25

26 Feb '25

Hi All,I am unable to click on any popup windows in my chimeraX installation. For eg: colour menu, once popped up, unable to click on any options.Ubuntu 22.04.5 LTS installed under WSL in Dell laptop. ChimeraX ver 1.9Error messages:NOTE: available bundle cache has not been initialized yetmalloc(): unsorted double linked list corruptedAborted (core dumped) Any suggestions.Thank you.Jobi

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Rotation using left mouse button
by y.v.hazendonk＠nki.nl 26 Feb '25

26 Feb '25

Hello, In my work with ChimeraX I have to rotate my proteins quite a lot to get a good look at different residues and helices. My problem is that very often when I am rotating my protein using the left mouse button, another piece of my protein will glide across my screen in the foreground, at which point the axis of rotation will lock onto this other piece. Is there a way to disable this unwanted locking? I am fine with these pieces floating across the foreground, as long as my axis of rotation doesn't suddenly lock onto them. I want the rotational axis to stay where it was when I started rotating. I look forward to your reply on how to fix this issue. Thank you in advance. With kind regards, Yorick van Hazendonk

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Communicate between multiple ChimeraX instances
by Roden Deng Luo 25 Feb '25

25 Feb '25

Hi, I wonder if there is a way to synchronize two or more ChimeraX instances/sessions. For example, sync the camera. The meeting command ( https://www.rbvi.ucsf.edu/chimerax/docs/user/commands/meeting.html) a great command I just got to know, is very close to what I am looking for. Only I will have different data in different instances, and toggles to enable and disable what features to be synced. If it is not currently implemented, how should I approach it as a developer? Many thanks, Roden -- This message and its contents, including attachments are intended solely for the original recipient. If you are not the intended recipient or have received this message in error, please notify me immediately and delete this message from your computer system. Any unauthorized use or distribution is prohibited. Please consider the environment before printing this email.

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Measure angle between domains in chimeraX
by junjie han 24 Feb '25

24 Feb '25

Hi Elaine, I hope this email finds you well. May I ask how to measure the angle between two domains from one molecule or two different molecules in ChimeraX. Here are some examples below. Example 1: [cid:ee5ac0af-a9be-4e98-bb7c-e555c8f183c2] How to calculate these angles (54°, 38°)？ Example 2: [cid:24512415-5303-4be2-8f61-a4fd6acdc0ee] How to calculate this angle (75°) ? Example 3: [cid:f3ed355d-a961-4647-8a3c-b39ab3875cb8] How can I measure the rotation angle between A and B, or between two specific regions of these two molecules in ChimeraX? If I need to calculate the rotation angles of two molecules relative to a specific molecule, how can I define a shared axis for calculating the rotation angles? The rotation axes are different when I use the command “measure rotation A toModel B” to calculate the rotation angles, which is not an ideal way to compare them in parallel. Thank you in advance for your any suggestions. Very appreciated, Junjie

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Trouble Morphing 2 Proteins
by Andrew Mejia Garnica 24 Feb '25

24 Feb '25

Hello, I have been using ChimeraX with a mac book from 2020 with a 1.1 GHz Dual-Core Intel Core i3, Intel Iris Plus Graphics 1536 MB and 8 GB of RAM. Everything seems to be working fine until I try to do a morph. Both proteins have been super positioned by matchmaker. I can only complete 5 frames out of the 60 with the command, morph #1,2 wrap true frames 60. However, I am not able to look through the frames, record or press play. I have tried it with the tutorial proteins as well and got stuck. The proteins that I am trying to morph will be attached to this email. I would like to ask if you could do a morphing for me or redirect me to be able to. I would also like to ask if it is a Graphis problem as I was also unsuccess full using a Dell laptop with a , 11th Gen Intel(R) Core(TM) i5-1135G7 @ 2.40GHZ, 16GB of RAM, 64-bit operating system, x64-based processor. Thank you for your time and I hope to hear from you soon. Best, Andrew

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