April 2022 - ChimeraX-users - RBVI Mailing Lists

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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ChimeraX - XMAS pluggin modification questions
by Moya Clark, I.O. de (Isabel) 31 May '22

31 May '22

Good morning, I am a student intern at the Richard Scheltema Laboratory, and I am going to be continuing with the modification of the XMAS bundle submitted to ChimeraX recently. Right now, we are trying to extend the bundle to be able to extract specific distances between specific amino acids for two different proteins but for a molecular dynamics simulation. Either by loading a trajectory coordinates + topology files or by using the “morph” command and then “coordset slider”. So, the idea would be to extract the distances between the alpha carbons, of a set of pre-selected amino acids, in each frame of the simulation. Do you have any suggestions about any modules or methods that I should look into to extract this information in each frame? I saw there is a CooordSets class but I do not know if this would be the right way to go about it. Kind regards, Isabel de Moya Clark

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Selecting atoms outside (or inside) a density map's contour
by Mateusz Dobrychłop 23 May '22

23 May '22

Dear ChimeraX Team, I'm a structural bioinformatician working on my PhD thesis. I've been a long time user of Chimera, and I'm now using ChimeraX to create figures for my dissertation. I genuinely love both programs. Thank you for creating them. I found myself stuck trying to perform one operation in ChimeraX that is very easy to perform in Chimera. What I'm trying to do is select (and color) all atoms of an atomic model, that are located outside of a density map's contour. In Chimera, I was able to just select the model and use the shortcut "ac oa" and that was it. Unfortunately I am not able to find a way to do that in ChimeraX. I even tried to select the atoms in Chimera, then save the selected atoms as a PDB file, and then the inverted selection as a separate PDB file, and then open the two files in ChimeraX and color them separately. This could even work for a full atom representation, but does not work well for ribbon representation. That said, if the solution to my problem could be to somehow transfer the list of atoms that are outside the map from Chimera to ChimeraX, that would work for me as well. I will appreciate any tips and suggestions! Kind regards, Mateusz

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Color by RMSD for nucleic acid
by Rundlet, Emily 03 May '22

03 May '22

Hi ChimeraX developers, Is there a way to color nucleic acids by seq_rmsd? When I use the following, no atoms are colored. mm #1 to #2 matrix Nucleic showAlignment true color byattribute seq_rmsd #2 Thank you in advance for your help! -Emily ________________________________ Email Disclaimer: www.stjude.org/emaildisclaimer Consultation Disclaimer: www.stjude.org/consultationdisclaimer

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Dali server alignment
by HONG ZHAN 02 May '22

02 May '22

Dear all, I am trying to align molecules based on Dali server output. However, I can’t download the superposition results from the Dali server webpage (or anyone know?), but I can generate an alignment file with 2D structural alignment from the Dali server. Is there a way to use matchmaker to superpose molecules based on output alignment from Dali server? How to run structure conservation calculation to color the molecule? If I just give Dali’s alignment file, it still calculate conservation based on sequence not structure. Best, Hong

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Re: [chimerax-users] ChimeraX question
by Tom Goddard 29 Apr '22

29 Apr '22

Hi Ryan, ChimeraX has a "morph" command. Here's an example using it open 2vaa open 2vab matchmaker #2 to #1 morph #1,2 save morph.pdb model #3 allCoordsets true Morphing of course only contains the atoms that are in both structures. So if you have an unbound and a bound state, and the bound tapasin is only in one structure then it will not be included in the morph since there is nothing to morph it to in the unbound state. You can delete chains that the two structures do not have in common before morphing, or you can use the same true option to the morph command "morph #1,2 same true" which will ignore chains which do not appear in both structures. Tom > On Apr 29, 2022, at 9:28 AM, Kissinger, Ryan (NIH/NIAID) [C] <ryan.kissinger(a)nih.gov> wrote: > > Hi Tom, > > I’m trying to create a morph animation in ChimeraX and I am having a lot of trouble finding decent tutorials online. I have pdb entries for unbound MHC1 and Tapasin and bound MHC1 and Tapasin. If possible I would like to morph between the bound and unbound forms. I would like to do this with ribbon and the atomic models. Any advice? > > Best Regards, > > Ryan

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Re: [chimerax-users] ChimeraX crossfade
by Elaine Meng 28 Apr '22

28 Apr '22

> On Apr 27, 2022, at 9:43 AM, Daisy Sassoon <DES867(a)student.bham.ac.uk> wrote: > > Hi Elaine, > I hope you are well. > I am currently making an animation using chimeraX and am having some issues using the crossfade command. Crossfade will successfully fade colour changes until I try and record the animation. When using movie record/encode, the crossfade function blacks out the entire screen. I have tried extending the wait times after but this does not change anything. > Do you have any advice? > > My code is shown below: > [... edited out by Elaine ...] > > Many thanks, > Daisy > > Sent from Mail for Windows Hi Daisy, I don't know why it doesn't work for you. I tried your script and for me, the recorded movie looks the same as what is shown interactively. Unless you are including data that needs to remain private, it is best to send questions to chimerax-users(a)cgl.ucsf.edu so that any other experts can respond, or if it is a bug, use Help... Report a Bug instead of sending e-mail. (Report a Bug will still send notifications to the team, including any information you type into the dialog plus other information like what ChimeraX version you are using and on what type of computer. It may be an issue with the graphics on your specific system.) I'm CC-ing chimerax-users(a)cgl.ucsf.edu on this reply but omitting your script in case it needs to remain private. However, here are some specific notes on the script: (1) the "view 3" command causes an error so I had to comment it out of your script to try it (2) there is no reason to "select all" unless you really want a green outline around everything, including the 2D label text (3) although your "crossfade 100" command works fine for me both with and without recording, you could also try using "movie crossfade frames 100" ... however, the results are slightly different. The crossfade command shows movement at the same time as the fade, whereas the movie crossfade command does not show any movement during the color fade. They are both valid commands, just different ones. <https://rbvi.ucsf.edu/chimerax/docs/user/commands/crossfade.html> <https://rbvi.ucsf.edu/chimerax/docs/user/commands/movie.html#crossfade> 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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Apple silicon (M1 chip) native version?
by Jeffrey D. Hartgerink 28 Apr '22

28 Apr '22

Are there any plans for an Apple Silicon (M1 chip) native version of ChimeraX? While things work ok via the Rosetta emulator, it would be great to have the performance from a native app. -------------------------------------- Jeffrey D. Hartgerink, Ph.D. Prof. of Chemistry and Bioengineering Rice University, MS 602 6100 Main Street Houston, TX 77005 jdh(a)rice.edu / 713-348-4142 hartgerink.rice.edu

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Can not save image as tiff format
by 张宁 27 Apr '22

27 Apr '22

Hello ChimeraX group, I want to save the image as tiff format, but it gives me the error "No map chosen to save", could you please help me address this issue? here are two screenshots. Thanks, Ning

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Re: [chimerax-users] [Chimera-users] Questions in ChimeraX comparing with Chimera
by Elaine Meng 27 Apr '22

27 Apr '22

Dear Long Gui, (1) There is no way to open more than one session file in the same instance of ChimeraX, sorry. You can open multiple data files, of course, and have multiple maps, structures, etc. all at the same time, just not from multiple session files. (2) I'm told that the current way to show solid style (also called image style in ChimeraX) planes with zero transparency is to use command volume #2 colormode l8 (the last thing is the letter L except lowercase l and the number 8). See image display options: <https://rbvi.ucsf.edu/chimerax/docs/user/commands/volume.html#dispsolid> Theoretically the following command should also work but currently does not: volume #2 transparency 0 ...although a low almost-zero number should work: volume #2 transparency 0.01 See general display options: <https://rbvi.ucsf.edu/chimerax/docs/user/commands/volume.html#general> I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco > On Apr 27, 2022, at 11:25 AM, Long Gui via Chimera-users <chimera-users(a)cgl.ucsf.edu> wrote: > > Dear Chimera users, > > I have been recently transferring to ChimeraX from the conventional Chimera and I am currently struggling with two features existing in Chimera but not in ChimeraX. > > • How could I combine two or several different ChimeraX files? I have been doing in Chimera as I was opening new chimera files by "Files...Open...", this is a window pop-up as the following and if I click "No", the new Chimera will be added to the cold Chimera as the old one was not closed. However, when I performed the similar operation in ChimeraX, there is no such window and the new ChimeraX would REPLACE the old one. I wonder if there is a way (probably using command to open? but I did not find the correct open options.) to open the new ChimeraX without closing the old one? > <save.png> > • I am also working with tomogram slices and cellular segmentation. Previously, in Chimera I can set this Transparency value to 0 and the Plane of the tomogram will be totally opaque. Now in ChimeraX I have used the command "transparency #2 0" (#2 is the tomogram files) but it still look quite different from my previous images in Chimera. Is there a way to set it up in ChimeraX so it could look similar as before? > <Transparency.png> > > Thanks again and I am very grateful if any advice or help could be provided. > > Long Gui, Ph.D. > Postdoc Researcher, Nicastro Lab > University of Texas Southwestern Medical Center

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ChimeraX-users April 2022