- ChimeraX-users - RBVI Mailing Lists

align peptide to model sequence
by Lagerwaard, I.M. (Ilse) 15 Jun '21

15 Jun '21

Hi everyone, I want to write a script that can align the sequences of peptides to a model sequence and return the identical residues. Because I am new to programming, I could really use some help to get started. Could I use the search() method of the Sequence class for this? And if so, how could I go about this? Kind regards Ilse Lagerwaard

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Mesh resolution/smoothness
by Saren Tasciyan 15 Jun '21

15 Jun '21

Hi, I am trying to generate STL files out of protein models. Often the problem is that the mesh doesn't as smooth as the models (see pics below). I wonder if this is an artifact of rendering in ChimeraX or the mesh is actually hard coded to have certain resolution, which makes it look like this? I tried to find out why and ended up in custom_x3d function but didn't notice anything. Post-export smoothing is an option but I wonder, if that's the optimal approach? Perhaps, smoothing can create collisions between 2 STL models, where a higher resolution export may avoid this. Best, Saren -- Saren Tasciyan /PhD Student / Sixt Group/ Institute of Science and Technology Austria Am Campus 1 3400 Klosterneuburg, Austria

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dual conformation
by Wen-Jin Winston Wu 15 Jun '21

15 Jun '21

Hi, I am trying to use Chimera X to display an amino acid with dual side chain conformations (PDB code: 7a5v) together with its cryoEM density map (EMDataResource: <https://www.emdataresource.org/EMD-11657> EMD-11657). For example, Tyr 66 have two side chain conformations, however using the command below, it only showed one conformation. resfit /a:66 map #1 (a very nice command, by the way) I then used Chimera 1.15 to view the PDB coordinate, and it showed two side chain conformations for Tyr66 (as I saw in PyMol); on the other hand, Chimera X only shows a single conformation. Is there any way to display the two alternative conformations using Chimera X? Thanks a lot for your time, and possible help! Best wishes, Winston ************************* ATOM 495 N ATYR A 66 124.799 162.717 112.222 0.50 11.67 N ATOM 496 N BTYR A 66 125.017 162.760 112.080 0.50 12.99 N ATOM 497 CA ATYR A 66 124.008 162.914 110.998 0.50 12.05 C ATOM 498 CA BTYR A 66 124.035 162.916 111.002 0.50 14.20 C ATOM 499 C ATYR A 66 124.638 164.062 110.190 0.50 11.84 C ATOM 500 C BTYR A 66 124.433 164.115 110.140 0.50 13.40 C ATOM 501 O ATYR A 66 125.008 165.077 110.788 0.50 11.86 O ATOM 502 O BTYR A 66 124.411 165.246 110.660 0.50 14.99 O ATOM 503 CB ATYR A 66 122.562 163.249 111.355 0.50 13.02 C ATOM 504 CB BTYR A 66 122.666 163.125 111.624 0.50 17.22 C ATOM 505 CG ATYR A 66 121.759 162.139 111.997 0.50 14.56 C ATOM 506 CG BTYR A 66 121.542 163.315 110.654 0.50 21.09 C ATOM 507 CD1ATYR A 66 121.860 161.839 113.348 0.50 16.21 C ATOM 508 CD1BTYR A 66 120.718 162.258 110.325 0.50 25.90 C ATOM 509 CD2ATYR A 66 120.832 161.436 111.248 0.50 17.74 C ATOM 510 CD2BTYR A 66 121.189 164.579 110.209 0.50 29.25 C ATOM 511 CE1ATYR A 66 120.974 160.942 113.960 0.50 18.53 C ATOM 512 CE1BTYR A 66 119.590 162.443 109.543 0.50 32.51 C ATOM 513 CE2ATYR A 66 119.990 160.494 111.824 0.50 18.57 C ATOM 514 CE2BTYR A 66 120.067 164.784 109.421 0.50 27.89 C ATOM 515 CZ ATYR A 66 120.076 160.228 113.177 0.50 20.29 C ATOM 516 CZ BTYR A 66 119.252 163.714 109.107 0.50 30.80 C ATOM 517 OH ATYR A 66 119.241 159.287 113.722 0.50 24.21 O ATOM 518 OH BTYR A 66 118.168 163.886 108.291 0.50 39.05

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using pandas
by Lagerwaard, I.M. (Ilse) 11 Jun '21

11 Jun '21

Hello everyone, Is it possible to use the pandas package in ChimeraX? I tried opening a Python script containing the line 'import pandas', but I get the error: 'ModuleNotFoundError: No module named 'pandas''. Kind regards, Ilse

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Independent centres of rotation
by Shahid, Taha (Dr.) 10 Jun '21

10 Jun '21

Hi, Is there a method, even if an indirect one via a long command or a series of commands, to set independent rotation centres for a series of (cryo-EM) maps that would then turn together. This could be easily achieved by 'set independent' in the original Chimera, and is much missed by our group of structural biologists. Kudos otherwise on a wonderful upgrade to the program. Many thanks, Taha

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Re: [chimerax-users] saving multiple .obj files from a morph
by Elaine Meng 09 Jun '21

09 Jun '21

On Jun 9, 2021, at 3:38 AM, Brett Murrah <murrahx5(a)att.net> wrote: > I’m trying my best to use the perframe command to save each frame / model out from a morph and slider animation after morphing some pdbs. It is exporting something.. but only 1k files. I’m not sure what I’m doing wrong. Any help? My command is this: > > perframe "save D:/Projects/OBJs/model$1.obj model #3.$1" frames 10 > > PS, I put model #3 because the ID’s for 1 and 2 are the models I used for the morphs. The final morph is #3. If I export each slider frame by hand.. that seems to work. Trying to automate it best I can. > > Thanks you for any help! > Brett Hi Brett, I'm guessing you meant to send this to chimerax-users(a)cgl.ucsf.edu (CC'd here, the recommended address for questions). The morph #3 is a trajectory model. It does not have the frames as submodels #3.1, 3.2, ... so your save command doesn't make sense. I don't know what you mean by "1k files" either... do you mean it makes 10 files but they are too small? You would use "perframe" in combination with "coordset" to replay the existing morph trajectory. E.g. put something like this into a command file (plain text named something.cxc) and then open it in ChimeraX: perframe "save D:/Projects/OBJs/model$1.obj models #3" coordset #3 1,10; wait 10 ~perframe <https://rbvi.ucsf.edu/chimerax/docs/user/commands/coordset.html> <https://rbvi.ucsf.edu/chimerax/docs/user/commands/perframe.html> <https://rbvi.ucsf.edu/chimerax/docs/user/commands/save.html> The reason I say to put it in a command file is to make the commands execute instantly one afer the other. I expected it to work when I entered them all as one long line in the command line (with semicolon separators) but then I got a parsing error, possibly due to a bug. E.g. I tried entering this as one long line (the mail tool may choose to break it up): perframe "save D:/Projects/OBJs/model$1.obj models #3"; coordset #3 1,10; wait 10; ~perframe ... but that gave an "incomplete quoted text" error which I will report as a bug. 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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Change default volume display settings?
by Oliver Clarke 08 Jun '21

08 Jun '21

Hi, Is there any way in ChimeraX to change default volume display settings? For example, I would like to set all volumes to "step 1" by default - in Chimera I can set these defaults in the Volume Viewer menu but I can't see an equivalent in ChimeraX. Sort of related - I wonder if it would be possible to have the option to set default display preferences for molecules or maps? Or more generally, have a script that executes when a file of a particular type is loaded - similar to how the startup commands are executed when ChimeraX is started, but triggered by the opening of a particular filetype and applied to that particular model? Cheers Oli

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Surface Coloring
by Juliana Glavina 07 Jun '21

07 Jun '21

Dear All, I am moving from Chimera to ChimeraX and I am trying to reproduce some of things that I used to do in Chimera. I managed to colour the surface by the kdHydrophobicity scale. However, the coloring is discrete with sharp edges between the residues. I was wondering if it was possible to smooth the edge between two different colors on the surface - similar to mlp but with customized attributes. Thank you very much in advance UCSF ChimeraX version: 1.2.3 (2021-05-13) Ubuntu 20.04 Juliana

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Re: [chimerax-users] Unit cell orientations
by Elaine Meng 04 Jun '21

04 Jun '21

> On Jun 4, 2021, at 10:39 AM, Silva, Chinthaka Mahesh <silva228(a)llnl.gov> wrote: > > Hi Elaine, > Is it possible to orient a unit cell along different axes in ChimeraX? I tried using ‘Unit cell’ option, but not sure if this is the correct place to do it. > Thanks! > -chinthaka Hi Chinthaka, (CC to chimerax-users(a)cgl.ucsf.edu ... please use that address for ChimeraX questions) Sorry, I don't understand the question. You can build the unit cell or a block of multiple unit cells with the Unit Cell tool: <https://rbvi.ucsf.edu/chimerax/docs/user/tools/unitcell.html> The axes of the unit cell are defined in the data... it is not something that you control. Of course, you can rotate it after you build it. Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco

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Consultation about developing plug-ins in ChimeraX
by Chen, Xiang 28 May '21

28 May '21

Dear Sir or Madam, I am a graduate student in the Department of Computer Science at the Memorial University of Newfoundland. I am currently engaged in developing and researching VR applications to visualize biological microstructures. I learned that Chimerax is a relatively mature piece of software, containing many excellent functions and features. So I'd like to know: 1. Is ChimeraX completely open-source and free? I will only use it for research and non-profit purposes. 2. If ChimeraX is open source, is there a description or summary of the structure/principles of the source code? (In order to learn what features are implemented by each code file.) 3. May I develop new plug-ins/bundles/modules based on ChimeraX's VR mode to implement one or more new features/functions? Could you please briefly describe the feasibility of developing it? Best regards, Xiang Chen --- Xiang Chen, M.Sc. # 201992538 Department of Computer Science Memorial University of Newfoundland St. John's, NL, Canada T (709) 219-2960 / E xiangc(a)mun.ca

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