November 2022 - ChimeraX-users - RBVI Mailing Lists

ChimeraX 1.5rc running on Nvidia RTX Titan [ubuntu 22.04]
by HONG ZHAN 11 Nov '22

11 Nov '22

Dear, I recently installed a Nvidia RTX Titan GPU card, and ChimeraX 1.5rc, it is a bit wired. I can open the window using intergrated GPU but if I just clicked on Chimerax or try to open it in terminal, it failed to open the program... Is ChimeraX only working on integrated GPU? Also, I cannot install the chimerax using apt install as in the website description, but dpkg -i works... is this the right way to install? many thanks! Hong

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.pdb from Protein Data Bank has more chains than expected
by McClean, Phillip 10 Nov '22

10 Nov '22

Hi Everyone, I downloaded the 7FDL .pdb from the Protein Data Bank. I was expecting just two chains (it is a heteromeric complex), but I found 12 chains in the file (A-L). I was expecting two chains because the manuscript suggested they were just modeling protein fragments of the two protein. It appears that chains that A,C,E,G,I,K are multiple models of one fragment, while chains B,D,F,H,J,L are multiple models of the second fragment. Two questions. Why are multiple structures reported, and how to I visualize just two fragments at the same time, for example A and B. I have attached the .pdb file. Thanks for any advise. Phil McClean

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Density extraction
by Dmitry Semchonok 09 Nov '22

09 Nov '22

Dear colleagues, I have a 3D map of the helix. 1. Do you know how can I extract 1 subunit? 2. Also, if there is no x-ray structure available. Thanks in advance. Kind regards, Dmitry

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Fast Archive Search
by Kazan Ramy 09 Nov '22

09 Nov '22

Greetings to all, How can one search the archive with given keywords? Like for example, Ctrl + F search. I can only find the manual search by subject, thread ... and limited by month. Cheers, Ramy

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Problem with the addcharge command
by svle＠tiscali.it 09 Nov '22

09 Nov '22

Hi all, for Chimerax version 1.4 (2022-06-03) when in the command line I use addcharge or addcharge #1 I receive in the Log panel the following: Unknown command: addcharge or Unknown command: addcharge #1. Where I'm wrong? Thanks. Saverio VOUCHER CONNETTIVITÀ per P.IVA e PMI: internet a canone 0 per 48 mesi. ATTIVA ORA https://casa.tiscali.it/promo/?u=https://promozioni.tiscali.it/voucher_busi…..

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Re: [chimerax-users] [Chimera-users] MD simulation movie in chimeraX
by Elaine Meng 09 Nov '22

09 Nov '22

Hello! For ChimeraX questions you may want to use the other address, chimerax-users(a)cgl.ucsf.edu CC'd here. You can see what formats ChimeraX reads by using command "open formats," or view this User Guide page: <https://rbvi.ucsf.edu/chimerax/docs/user/commands/open.html#formats> <https://rbvi.ucsf.edu/chimerax/docs/user/commands/open.html#trajectory> ChimeraX can read .trr trajectory coordinates, but it cannot read .tpr trajectory topology. If your MD program can output a single PDB snapshot you can use that for the topology. First you would open the PDB file. Then to open the .trr file you would need to use the "open" command and also specify the already-open PDB file with the "structureModel" option. For example, if you open the PDB file as model #1, then something like: open myfile.trr structureModel #1 See details and more examples: <https://rbvi.ucsf.edu/chimerax/docs/user/commands/open.html#traj-options> <https://rbvi.ucsf.edu/chimerax/docs/user/commands/open.html#structureModel> When you open the trajectory in ChimeraX, I believe that a playback slider will automatically appear. However, if it does not you can use "coordset slider" to show it. The "coordset" command can also be used to play the trajectory frames directly (not using the interactive slider): <https://rbvi.ucsf.edu/chimerax/docs/user/commands/coordset.html> I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco > On Nov 8, 2022, at 6:17 PM, Shivam Gupta via Chimera-users <chimera-users(a)cgl.ucsf.edu> wrote: > > Hello Support Team, > > I am a commercial license user of chimeraX. I have .trr and .tpr files from the Gromacs MD simulation. I am not getting any option to create an MD movie. I know how to do it in chimera but couldn't find a similar GUI/option in chimeraX. Literature/tutorial of chimeraX didn't help me much. > > Please help me out by guiding me to generate MD movies. > Please reply to this email inline. > > I am Looking forward to hearing from you. > Thanks > > -- > With Regards > Gupta　Shivam グプタ　シヴァム > E-mail: shivam-gupta(a)pharmafoods.co.jp > Biomedical Department > Pharma Foods International, Kyoto Japan > 株式会社ファーマフーズ > 〒615-8245　京都市西京区御陵大原1-49 > TEL:075-748-9811 > FAX:075-948-9818 > URL: http://www.pharmafoods.co.jp/

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side view window : lines are too thin
by Valerie Biou 08 Nov '22

08 Nov '22

Hello, I am a Chimera user slowly adapting to ChimeraX. I find that the moving lines in the Side view window are very thin, almost invisible when a cryoem map is displayed. is there a way to make them thicker ? thanks, kind regards, Valérie

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RMSD Problem
by Timothy JM Clayson 08 Nov '22

08 Nov '22

Hiya, I am currently having a problem when trying to use RMSD on 2 sequences. *I am using the command: * *rmsd #1:149,264 to #2:469,553* (where a.a. on chain 1 are 149-264 and on chain 2 they're 469-553) *It is coming up with the error:* *'Number of atoms from first atom spec (21) differs from number in second (10)'* I was wondering if there is a fix to this problem? Thanks, Tim

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Re: [chimerax-users] Applying symmetry operations to generate an oligomeric model
by Tom Goddard 07 Nov '22

07 Nov '22

Hi Rob, Hopefully you are using ChimeraX, not Chimera -- we have only done maintenance on Chimera for the past 6 years. The ChimeraX commands all work in physical coordinates (Angstroms), not grid index units (pixels), and usually they use scene coordinates, not local model coordinates which makes a difference if you have moved individual models relative to one another in the scene. Your Dn symmetry problems are because the two-fold symmetry that flips one Cn ring to the other stacked Cn ring needs to be aligned on the x-axis. In your map apparently it is not aligned with the x-axis. In general it is helpful to have your map aligned in a standard way if you will be applying symmetry. For dihedral symmetry the z-axis is the cyclic symmetry axis, the origin should be on that cyclic symmetry axis mid-way between the two rings, and the x-axis should be a two-fold symmetry axis. If you don't use standard map orientations for symmetric maps it is going to be very painful to make symmetric copies of atomic models in those maps. Tom > On Nov 6, 2022, at 12:58 PM, Robert Harkness <r.harkness(a)utoronto.ca> wrote: > > Hi Tom, > > Thank you for your detailed response! > > I think I am using an older version of chimera. When I use the center <map> command, I just get one line of output that corresponds to the center of the map in grid coordinates. I have been converting these into angstrom coordinates using the pixel size and applying those in sym. > > Sometimes when I open a model and a map, I have to rotate and translate the model into a reasonable position inside the map and then do a “fit in map” to get the initial placement for sym, so this means that the model’s coordinates will now be different relative to the scene and the map. If I save the fitted model to a new PDB and then re-open it, will it now have the same coordinates of the scene (and map if I haven’t moved the map at all)? I think that way I can use scene coordinates for all maps and models. > > I am finding for other cages I am working on that have Dn symmetry, in some cases they work beautifully if I just fit the model into the portion of the map that corresponds to one unit of the cage, then save that model as a PDB relative to the map, then open it and use sym <model> group <Dn> center <map center in angstrom units> coordinateSystem <map>. In other cases doing this same procedure, the first half of the cage units are made perfectly as sym goes from the initial model around the Cn axis placing copies in the density, but when it flips over the 2-fold axis to do the other half, the model units are out of alignment with the density. So I have been adding the axis option to get it closer but find it requires a little tweaking. I guess the axis command doesn’t always give the perfect axis of rotation because the map is not perfect. Will this also be alleviated by just using everything in scene coordinates? > > Best, > > Rob > >> On Nov 5, 2022, at 7:55 PM, Tom Goddard <goddard(a)sonic.net <mailto:goddard@sonic.net>> wrote: >> >> You don't often get email from goddard(a)sonic.net <mailto:goddard@sonic.net>. Learn why this is important <https://aka.ms/LearnAboutSenderIdentification> >> Hi Rob, >> >> It sounds like you did everything right. Using "measure center #1" where model #1 is the map should give the right center of the tetrahedron. When you use that command it reports the center in map grid index units and also in scene coordinates, for example, >> >> measure center #1 <cxcmd:measure center #1>Center of mass grid index for emdb 15560 = (279.52, 279.92, 253.25) >> Center of mass xyz coordinates for emdb 15560 = (289.20, 235.85, 185.32) >> >> >> In the sym command were you use that center to copy your atomic model with tetrahedral symmetry you should use the scene coordinates (the second line of output) not the grid index coordinates. The "sym" command expects scene coordinates for the "center" option and you should not use the "sym" command coordinateSystem option. The coordinateSystem option is used only if the center coordinates are given in the coordinate system of a specific model rather than the whole scene. The models start out with the same coordinate system as the whole scene, but if you move a model in the scene (e.g. when you fit an atomic model into the map) then that model has different local coordinates than the scene. >> >> I see another potential problem in your sym command. The "axis" option is supposed to be a 3-fold symmetry axis of the tetrahedron. You are giving it the symmetry axis of the asymmetric unit trimer which may or may not be a symmetry axis of the tetrahedron. To determine the symmetry axis of the tetrahedron open two copies of the map and rotate one copy by hand using the "Move Model" mouse mode (which moves only the selected model) to roughly align two different trimeric subunits then optimize the alignment with "fitmap #2 in #1", then use measure rotation #2 to #1 and it will report a symmetry axis of the tetrahedron. Another way to go about this is if you density map already has a standard orientation, such as tetrahedron 2-fold symmetry axes along x,y,z then you don't need to specify the axis in the sym command, just use "t,222" in the sym command. Or if it has a symmetry axis along z use "t,z3" with no axis specification. You can probably see if it has a standard symmetry using "measure symmetry #1". >> >> Sorry for the delayed answer. I was at a workshop all last week and did not have time for email. >> >> Tom >> >>> On Nov 3, 2022, at 4:35 AM, Robert Harkness via ChimeraX-users <chimerax-users(a)cgl.ucsf.edu <mailto:chimerax-users@cgl.ucsf.edu>> wrote: >>> >>> Hello, >>> >>> I am trying to generate a model of an oligomeric protein cage that consists of 4 trimers and has tetrahedral symmetry. I am using the asymmetric unit model consisting of one monomer (#0) and a density map (#1) as a starting point. My strategy has been to take the asymmetric unit and fit it into a portion of the map corresponding to one of the monomers within one of the trimer faces of the tetrahedron. Then I generate a copy of that asymmetric unit (#2) and fit it into the map for an adjacent protomer within the same trimer face. This results in the two asymmetric unit models being rotated 120 degrees relative to one another and part of the same trimer. Then I use the measure rotation command to measure the rotation of the second asymmetric unit relative to the first, giving me a rotation matrix and axis parameters. I then do >>> >>> sym #0 (first asymmetric unit) group t,z3 axis <axis from measure rotation> center <axis points from measure rotation> coordinateSystem #1 (the density map) >>> >>> And this generates the right looking trimers, so the 3-fold axis appears to be correct, but the center is off such that only one of the four trimers matches the density map and is placed at the top of the tetrahedron, while the other 3 trimers are off into the void of the scene but placed at the other 3 vertices. I am not sure how to appropriately define the center. My feeling is that it should be the center of the map, taken from the measure center #1 command, but implementing those numbers in sym doesn’t work either. Any thoughts on how these center coordinates are defined/should be measured, or if there is a better approach for doing this would be awesome! >>> >>> Best, >>> >>> Rob >>> >>> _______________________________________________ >>> ChimeraX-users mailing list >>> ChimeraX-users(a)cgl.ucsf.edu <mailto:ChimeraX-users@cgl.ucsf.edu> >>> Manage subscription: >>> https://www.rbvi.ucsf.edu/mailman/listinfo/chimerax-users <https://www.rbvi.ucsf.edu/mailman/listinfo/chimerax-users> >>> >> >

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error saving session in v 1.5
by Yoda Muppet 07 Nov '22

07 Nov '22

Greetings. We're having an issue savings session with ChimeraX 1.5. Trying to save a session file results in the following error: [save] (help: user/commands/save.html) /data/processed/staggers/cryofib- tryps/process/YTAT9-1 lamella4 0206 def -5 110e tilt-7/full seg session.cxs [save /data/processed/staggers/cryofib- tryps/process/YTAT9 - 1 lamella4 0206 def -5 110e tilt-7/full seg session.cxs] (cxcmd: save /data/processed/staggers/cryofib- tryps/process/YTAT9 - 1 lamella4 0206 def -5 110e tilt-7/full seg session.cxs) Traceback (most recent call last) : File "/opt/cryoem/chimerax-2022.10.28/lib/python3.9/site- packages/chimerax/core/session.py", line 285, in process data = sm. take snapshot (obj session, self.-state flags) File "/opt/cryoem/chimerax-2022.10.28/lib/python3.9/site- packages/chimerax/log/tool.py", line 542, in take snapshot "contents': self.page source, AttributeError: *Log' object has no attribute 'page source' The above exception was the direct cause of the following exception: Traceback (most recent call last) : File "/opt/cryoem/chimerax-2022.10.28/lib/python3.9/site- packages/chimerax/core/session.py", line 262, in discovery self.processed[key] = self.process (obj, parents) File "/opt/cryoem/chimerax-2022.10.28/lib/python3.9/site- packages/chimerax/core/session.py", line 290, in process raise RuntimeError (msg) from e RuntimeError: Error while saving session data for "tools' -> ‹chimerax.core. tools. Tools object at 0x7f90efeb0310> => <chimerax.log. tool. Log object at 0x7f90ee2b3c10> During handling of the above exception, another exception occurred: Traceback (most recent call last) : File "/opt/cryoem/chimerax-2022.10.28/lib/python3.9/site- packages/chimerax/core/session.py", line 896, in save session. save (output, version=version, include maps=include maps) File "/opt/cryoem/chimerax-2022.10.28/lib/python3.9/site- packages/chimerax/core/session.py" line 625, in save mgr.discovery(self. state containers) File "/opt/cryoem/chimerax-2022.10.28/lib/python3.9/site- packages/chimerax/core/session.py", line 266, in discovery raise ValueError ("error processing: %S: %S" % ( obj stack(parents, obj), e)) ValueError: error processing: "tools' <chimerax.core. tools. Tools object at 0x7 f90efeb0310> <chimerax.log. tool.Log object at 0x7f90ee2b3c10>: Error while saving session data for 'tools' -> <chimerax.core. tools. Tools object at 0x7f90efeb0310> <chimerax.log. tool. Log object at 0x7f90ee2b3c10> BUG: ValueError: error processing: 'tools' for "tools => -> ->: Error while saving session data File "/opt/cryoem/chimerax-2022.10.28/lib/python3.9/site- packages/chimerax/core/session.py" line 266, in discovery raise ValueError ("error processing: %S: %5" % (obj stack(parents, obj), e)) See log for complete Python traceback.

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