January 2023 - ChimeraX-users - RBVI Mailing Lists

Surface dust command in the .cxc script
by 李泽 24 Feb '25

24 Feb '25

Hi all: I'm trying to use the .cxc script to run the software, I found that the "surface dust" command has never been executed in it. Have anyone met the same problem? Any suggestions. Thank you all. Best, Ze

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Get color code of a custom color
by Ahmad Khalifa 11 Feb '25

11 Feb '25

I created a custom color that I want to use in a different session. is there a way to do that besides trying to match colors by eye? Regards.

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Double and Triple Bond Stick Style
by Smith, Chase 05 Feb '25

05 Feb '25

Dear ChimeraX, I was just wondering why there is no way to represent a double or triple bond in either the ligands or the protein amino acids when viewing as a Stick or Ball-and-Stick representation? I sometimes use Chimera or ChimeraX to make visuals for my lectures, and the students often have difficulty in understanding due to the absence of the multiple bonds. I would love to have the ability to represent the double or triple bonds with multiple lines between the atoms. Thank you, Chase Smith ... ChaseSmith, PhD Chair, Department of Pharmaceutical Sciences & Associate Professor of Medicinal Chemistry School of Pharmacy MCPHS University 19 Foster Street | WorcesterMA01608 T 508.373.5717F 508.890.5618C 978.855.7203 chase.smith(a)mcphs.edu www.mcphs.edu MCPHS University Confidentiality Note: This e-mail, and any attachment to it, is intended to be confidential and might be legally privileged. It is intended solely for the use of the addressee. If you are not the intended recipient, you are hereby notified that reading, copying, disseminating or distributing this email is strictly prohibited. If you have received this e-mail in error, please immediately return it to the sender and delete it from your system. Thank you.

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Quest 2 Support?
by Blaine Hewitt 27 Dec '24

27 Dec '24

Hello, my name is Blaine Hewitt. Now I know that you have stated previously that you have no intention of bringing support to the Oculus Quest. Which is completely understandable since I know that not only would you have to develop around a completely new Operating System but another CPU architecture and much much more I assume. But with the soon release of the Oculus Quest 2 and it's new XR 2 chip-set makes a pretty good argument for it. As this would allow for much easier use in education (as is what I am attempting to do with it). I think it will be even easier now to push updates with SideQuest <https://sidequestvr.com/> being relatively simple to setup. I know that another (Naome <https://blog.matryx.ai/nanome-on-quest-public-beta-is-now-available-b546321…>) program is already available on the platform. But I do like your program a lot more since it is able to be used for free unlike Nanome Pricing <https://nanome.ai/pricing/> which is... as to say unappealing to public schools (such as mine). I was was also thinking (sorry if I am becoming annoying at this point) that if you do make a version of the Quest that you could make that GitHub branch available to the public. As for example while I may not be great at understanding complex protein structures I can help to make the whole experience more user friendly. Anyways if you read this far thank you for taking time from your day to read this. If you want to know who I am, my name is Blaine I am in my senior year of High School (Waynecsd <https://wh.waynecsd.org/>). I have to do a project by the end of the year where I have to present an area of study I want to pursue and I decided to research the effects of VR on the human's ability to learn and retain information. Budget..... None

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ISOLDE and secondary structure restraints
by Guido Hansen 17 Nov '23

17 Nov '23

Hi all, I just started model building in cryoEM maps and get great results using ISOLDE on AlphaFold2-derived initial models. I have a question which is mainly directed to Tristan I guess: Is is possible to use the command line/script to apply secondary structure restraints in ISOLDE? I would like to restrain the initial secondary structure assignment from Alphafold especially at resolution worse than 3.5 A. At the moment I select each and every residue range assigned to helix, parallel or antiparallel beta-strand one after the other and turn on the corresponding restrains in the ISOLDE GUI. Is there a better way via command line of script? Cheers, Guido -- PD Dr. Guido Hansen Group Leader UNIVERSITÄT ZU LÜBECK INSTITUT FÜR BIOCHEMIE Tel +49 451 3101 3122 Fax +49 451 3101 3104 E-Mail hansen(a)biochem.uni-luebeck.de www.biochem.uni-luebeck.de [1] Ratzeburger Allee 160 23562 Lübeck Links: ------ [1] http://www.biochem.uni-luebeck.de

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Feature request: replace residues in model with residues from other model
by Vorländer,Matthias Kopano 17 Nov '23

17 Nov '23

Dear ChimeraX team, Thanks a lot for developing the amazing tool that is ChimeraX! I use it extensively for model building, and would like to request a functionality to replace a residue selection in one model from residues in another model (similar to what is possible in coot via the replace fragment functionality). I am aware that this currently possible by a combination of delete, combine, and changechains, but it would be great if this could be shortcutted. Many thanks in advance, Matthias

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Trajectory smoothing
by Shubham Devesh Ramgoolam 16 May '23

16 May '23

Hi all, Does chimeraX has a command for trajectory smoothing? Based on previous similar questions, I know a script was written for trajectory smoothing in chimera/chimeraX. However, I cannot not access this script because it is not found on the server anymore. Shubham Sent from Mail<https://go.microsoft.com/fwlink/?LinkId=550986> for Windows

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Multi-chain single macromolecule .pdb file read as two molecules
by Lenye Dlamini 31 Jan '23

31 Jan '23

Hello, I have a homo-oligomeric model that I've refined using phenix and the ISOLDE tool in ChimeraX that's read during deposition as 2 separate molecules, a larger 14mer and a smaller tetramer. It's read as one molecule in Coot, Chimera and Pymol but read as two distinct molecules in ChimeraX exactly like the deposition. I found this curious and thought that perhaps you might have some idea of what's wrong with the file. There is nothing that appears obviously incorrect to me in the text of the .pdb file, all TER cards follow the chains and all amino acids and their identifiers are in sequence and correct. I'd appreciate any ideas you may have and I'm happy to send the file to you if you prefer. Thank you, Kind regards, Lenye Dlamini Disclaimer - University of Cape Town This email is subject to UCT policies and email disclaimer published on our website at http://www.uct.ac.za/main/email-disclaimer or obtainable from +27 21 650 9111. If this email is not related to the business of UCT, it is sent by the sender in an individual capacity. Please report security incidents or abuse via https://csirt.uct.ac.za/page/report-an-incident.php.

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Fwd: EMDB-SFF segmentation file: application of transform 0 for image-to-physical projection
by Eric Pettersen 31 Jan '23

31 Jan '23

> Begin forwarded message: > > From: Tom Goddard <goddard(a)sonic.net> > Subject: Re: [chimerax-users] EMDB-SFF segmentation file: application of transform 0 for image-to-physical projection > Date: January 30, 2023 at 11:54:02 AM PST > To: Paul Korir > Cc: Martin Schorb > > Hi Paul, > > ChimeraX does not specify what distance units the open models use. For atomic structures and cryoEM map it is usually Angstroms. For light microscopy images it is often microns. For medical image scans (MRI, CAT) it is I think meters. The file formats for the data define the physical distance units, not ChimeraX. So if EMDB SFF provides a segmentation for say an MRC or CCP4 density map file the scaling of that density map in the ChimeraX graphics is taken from the file header which has a field "cell dimensions in Angstroms". If a segmentation of that density map is made that is say a bounding surface it might use x,y,z coordinates in Angstroms or it might use grid index units when it writes out a file, that would depend on the segmentation file format and the software that is writing the segmentation. In ChimeraX it always tries to scale the data into physical units so that different data sets, like an atomic structure and 3D image data have the correct relative scale. So ChimeraX never displays images using grid index units. > > So from what you say about EMDB SFF the first transform goes from grid index units to physical units and ChimeraX should apply that transformation to the segmentation data so that it has the same scaling as the map data that the segmentation was derived from. I see there is a function in the ChimeraX EMDB SFF file reader called "guess_scale_and_shift" that is trying to figure out what transform to apply, but it is just a hack and looks for any non-identity transform. > > https://github.com/RBVI/ChimeraX/blob/da72f2cd9b23c0c35a66122b7edc453d593ea… <https://github.com/RBVI/ChimeraX/blob/da72f2cd9b23c0c35a66122b7edc453d593ea…> > > And another comment in the code suggests it is doing that hack because it was needed for EMDB SFF test data EMDB 1547. > > If I understand you correctly ChimeraX should instead always apply the first transform from transforms_list. I can make that change. The main thing will be to test it on pairs of EMDB SFF segmentations and corresponding maps to make sure it produces the correct alignment. > > Tom > > >> On Jan 30, 2023, at 2:20 AM, Paul Korir via ChimeraX-users <chimerax-users(a)cgl.ucsf.edu> wrote: >> >> Hi Tom/ChimeraX admin, >> >> Just to clarify: what are the units of physical space in ChimeraX: Å or nm? >> >> Kind regards, >> >> Paul K. Korir, PhD >> 3D Visualisation Lead >> CS3DB >> EMBL-EBI >> >> On 30/01/2023 08:51, Paul Korir wrote: >>> Hi Tom, >>> >>> To the best of my understanding, ChimeraX displays images and associated segmentations in physical space not image space. However, segmentations are performed in image space. EMDB-SFF uses the first transform in the transforms_list field (with id=0) as the image-to-physical transform. (https://emdb-empiar.github.io/EMDB-SFF/v0.8.0.dev1/segmentation_da_xsd.html… <https://emdb-empiar.github.io/EMDB-SFF/v0.8.0.dev1/segmentation_da_xsd.html…>) >>> >>> I've tested with two files having the same segmentation but different values for transform 0 and they render the same. >>> >>> Could you please implement this feature in ChimeraX? >>> >>> Kind regards, >>> >>> -- >>> Paul K. Korir, PhD >>> 3D Visualisation Lead >>> CS3DB >>> EMBL-EBI >>> >> _______________________________________________ >> ChimeraX-users mailing list >> ChimeraX-users(a)cgl.ucsf.edu >> Manage subscription: >> https://www.rbvi.ucsf.edu/mailman/listinfo/chimerax-users >

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EMDB-SFF segmentation file: application of transform 0 for image-to-physical projection
by Paul Korir 30 Jan '23

30 Jan '23

Hi Tom, To the best of my understanding, ChimeraX displays images and associated segmentations in physical space not image space. However, segmentations are performed in image space. EMDB-SFF uses the first transform in the transforms_list field (with id=0) as the image-to-physical transform. (https://emdb-empiar.github.io/EMDB-SFF/v0.8.0.dev1/segmentation_da_xsd.html… <https://emdb-empiar.github.io/EMDB-SFF/v0.8.0.dev1/segmentation_da_xsd.html…>) I've tested with two files having the same segmentation but different values for transform 0 and they render the same. Could you please implement this feature in ChimeraX? Kind regards, -- Paul K. Korir, PhD 3D Visualisation Lead CS3DB EMBL-EBI

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