- Chimera-users - RBVI Mailing Lists

Opening .py files
by Henry Shook 04 Jan '22

04 Jan '22

Chimera User Support, I'm working on dockprepping the sars-2 main protease and whenever I try and save it as a .py file, I can't open it from sources other than the saved session I wrote. Whenever I try and open it from a dropbox or my finder, I get the message: Error while processing /Users/8642165/Desktop/Research/DC AP Research /[7l0d]DOCKPREPPEDFINAL.py: File "[7l0d]DOCKPREPPEDFINAL.py", line 1 @<TRIPOS>MOLECULE ^ SyntaxError: invalid syntax File "/Applications/Chimera.app/Contents/Resources/share/chimera/__init__.py", line 1325, in _openPython loadFunc(sandboxName, fileName, f) See reply log for Python traceback. Is there any way that I can fix this problem? Thanks, Henry Shook

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Helix Display Artefact
by Sebastian Guettler 28 Dec '21

28 Dec '21

Dear Chimera users, I have a problem with what I think is some sort of a helix display artefact is UCSF Chimera (including the latest release, 1.16). I attach an image. In cartoon display, the helix appears turned inside out for the last turn. It is displayed normally in ChimeraX and PyMol, and the display problem is independent of the secondary structure assignment algorithm (dssp, ksdssp, Stride). Any suggestions on how to solve this issue are welcome. Thank you, Sebastian --------------------------------------------- Sebastian Guettler, PhD Team Leader The Institute of Cancer Research (ICR) Divisions of Structural Biology and Cancer Biology London, UK --------------------------------------------- [cid:image001.jpg@01D7FC0A.1ED3ABA0] The Institute of Cancer Research: Royal Cancer Hospital, a charitable Company Limited by Guarantee, Registered in England under Company No. 534147 with its Registered Office at 123 Old Brompton Road, London SW7 3RP. This e-mail message is confidential and for use by the addressee only. If the message is received by anyone other than the addressee, please return the message to the sender by replying to it and then delete the message from your computer and network.

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Blank screen after MD simulations
by Sri Oruganty 28 Dec '21

28 Dec '21

Hello, I am a senior in high school, and I was interested in learning about proteins and mutations. I download Chimera to run MD simulations on a specific protein, but not all the frames are loading. After the frame number gets to a certain point (i.e. 14) every subsequent frame is completely blank. Why is this happening? Best regards, Srigouri Oruganty Pronouns: She, her, hers sri.oruganty(a)gmail.com (610)-207-6325

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Problem related to the "Near" atom in the "Adjust Torsions" tool of UCSF chimera
by Prathvi Singh 27 Dec '21

27 Dec '21

Hi Elaine, I have one more query. I have a residue (its ID is #0:140.a) in a protein model. I want to change the torsion angle between its backbone N, backbone C-alpha, sidechain C-beta & sidechain C-gamma. In order to do that, I execute the following command: rotation 1 :140.a@CA,140.a@CB The execution activates the torsion & lists it in the "Adjust Torsions" tool. However, I have noticed that the "near" atom in the "Adjust Torsions" tool is sometimes assigned to backbone N & other times is assigned to backbone C. This is messing up my calculations. Is there a way to fix the "near" atom to backbone N so that it does not change to backbone C? Thanks again -- Prathvi Singh, Research Fellow, Department of Biological Sciences & Bioengineering, Indian Institute of Technology, Kanpur-208016

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Move models around independent of each other in Chimera X
by Prathvi Singh 24 Dec '21

24 Dec '21

Hi, First of all, thank a million to the chimera X development team for incorporating the drag & drop feature in chimera X. I really missed it in chimera. However, after opening two models in the same window, I am unable to find a way to move/rotate model-1 in such a way that it does not move/rotate model-2. I could do this in chimera by unchecking the box for model-2 but when I do the same in chimera-X, it doesn't seem to work. Also, I am unable to find a way to disable depth cueing in chimera X. Please help. Thank you -- Prathvi Singh, Research Fellow, Department of Biological Sciences & Bioengineering, Indian Institute of Technology, Kanpur-208016

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Fwd: Chimera bug report submission
by Eric Pettersen 22 Dec '21

22 Dec '21

> Begin forwarded message: > > From: Kenji Matsui <s214903z(a)st.go.tuat.ac.jp> > Subject: Chimera bug report submission > Date: December 19, 2021 at 11:33:41 PM PST > To: chimera-bugs(a)cgl.ucsf.edu > > The following bug report has been submitted: > Platform: windows_x86_64 > Chimera Version: 1.16 > Description > I would like to see the interaction between the ligand and the protein, but I was not able to display it in the way described in the tutorial. How can I do that? > > Method > select →ligand > > Tool Structure analysis Find H-bond Line length 3.0 Å > > check Relax H-bond ~, Only find, Include intera-molecular, Include intra-residue > > apply →OK > File attachment: osh4,OSW-1220.py

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1.16 release
by Eric Pettersen 20 Dec '21

20 Dec '21

Chimera production release 1.16 is now available <https://www.cgl.ucsf.edu/chimera/download.html>. This will be the last release to support Windows 7. See the release notes <https://www.cgl.ucsf.edu/chimera/docs/relnotes/1.16.html> for what's new. --Eric Eric Pettersen UCSF Computer Graphics Lab

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Re: [Chimera-users] .dae export for ChimeraX
by Tom Goddard 19 Dec '21

19 Dec '21

Hi Byrne, Thanks for the info about exporting models for iOS. Glad you found a way to export a virus model from ChimeraX suitable for use in iOS apps made with Xcode. The STL format is just a list of triangles, each with 3 vertex (x,y,z) coordinates, used mostly for 3D printing. It does not have vertex normal vectors which are used to give smoother lighting. In the future maybe ChimeraX will directly export Collada (*.dae) files and you will be able to export a usable model without running it through Blender. As I mentioned before we support GLTF but not Collada currently. Our ChimeraX efforts are mostly to help researchers analyze molecular structures so adding this does not have highest priority. Unfortunately there are hundreds of feature requests we do not have time to implement with our limited funding. Tom > On Dec 18, 2021, at 9:34 AM, Byrne Pedit <bpedit(a)comcast.net> wrote: > > Hello again Tom, > > A follow-up follow-up. After extensive testing I have found a useable workflow from ChimeraX to iOS. Of course iOS apps may utilize PDB viewers, this is for folks who may want to incorporate models, in customized ways, into SceneKit for manipulation. > > ChimeraX ––> STL ––(graphics editor)––> DAE ––Xcode––> SCN > > • In Chimera > – reduce polys as much as possible* > – export individual elements, e.g. chains, if you want individual control (materials, etc) > • In a graphics editor: > – eliminate polygonal faceting of STL files > - Blender, check Auto Smooth in addition to toggling on Smooth Shading > - Cinema 4D, add a phong tag > – recenter if desired, add additional elements > > *You might want to add surfaces to your reducing file-size tutorial. In the model below, the spike's resolution was set to 7, gridSpacing 3. You also need to click Hide for Atoms and Cartoons; otherwise they will severely bloat the file even though not seen. The entire file size of this SARS-CoV-2 model, as used by iOS, is 1.2 Mb (all but one of the spikes are all clones). > > Thanks again for the help, > > Byrne > > > > > > >> On Dec 3, 2021, at 11:00 PM, Tom Goddard <goddard(a)sonic.net <mailto:goddard@sonic.net>> wrote: >> >> Hi Byrne, >> >> Thanks! So Blender can convert GLTF to Collada. The ChimeraX GLTF is binary and Collada is all text, so no surprise that the file size is much larger. If we add Collada support it would be produced directly from the ChimeraX scene, not converting from GLTF. But we have hundreds of new feature requests so I don't think Collada output is likely to be added soon, unless a funded project needs it. >> >> Tom >> >>> On Dec 3, 2021, at 9:48 AM, Byrne Pedit <bpedit(a)comcast.net <mailto:bpedit@comcast.net>> wrote: >>> >>> Hi Tom, >>> >>> A follow-up for future reference. Blender, the one recommendation I found on StackOverflow, is indeed capable of converting GLTF to DAE. But the conversion bloats the files by as much as 10x! In addition, the hierarchy is only partially preserved. I tried an on-line converter with even less satisfactory results. So I think this pathway is a bust. This might serve as a fair warning for ChimeraX developers to avoid an internal conversion from GLTF if introducing a DAE export option. >>> >>> >>> Byrne >>> >>> >>> >>> >>>> On Dec 2, 2021, at 2:22 PM, Tom Goddard <goddard(a)sonic.net <mailto:goddard@sonic.net>> wrote: >>>> >>>> Hi Byrne, >>>> >>>> I agree, OBJ and STL are very limited compared to Collada and GLTF. OBJ is supported by almost every 3D model program and STL is commonly used for 3D printing (single color) which is why they are in ChimeraX. GLTF is definitely the best option in ChimeraX for your case. >>>> >>>> There appear to be lots of programs that convert GLTF to Collada and the other direction too. But I have not tried any of them so don't have any recommendation. Let us know if you find one that works well -- other ChimeraX users may have the same need. >>>> >>>> A major stumbling block exporting 3D models from ChimeraX (or Chimera) is that they use vertex colors, while most of the non-biology 3D model world uses texture colors, and will simply ignore vertex colors losing all your color information. That example I linked to in the last email describes a relatively new ChimeraX feature to export texture colors (for limited cases, e.g. discrete colors only). >>>> >>>> Another common problem exporting molecular models for use in other software is that the file size and number of triangles is too large for the application that you want to use them in, often tens of millions of triangles or hundreds of Mbytes to Gbytes in size. The example also shows how to tell ChimeraX to limit the number of triangles. >>>> >>>> https://www.rbvi.ucsf.edu/chimerax/data/texture-may2021/export_3d.html <https://www.rbvi.ucsf.edu/chimerax/data/texture-may2021/export_3d.html> >>>> >>>> Tom >>>> >>>> Model from gltf export from linked ChimeraX example >>>> >>>> <spike.png> >>>> >>>> >>>>> On Dec 2, 2021, at 2:04 PM, Byrne Pedit <bpedit(a)comcast.net <mailto:bpedit@comcast.net>> wrote: >>>>> >>>>> Hello Tom, >>>>> >>>>> Thanks for the response. I tried the GLTF export, not recognizable by Xcode (the development platform for iOS and Mac OS). The only ChimeraX file options I’ve found to be openable are OBJ and STL. These are, however, problematic and unusable. >>>>> >>>>> But your hint of using GLTF as an intermediary offers an avenue for exploration, it’s not a format I’ve used. I see it supports scene graph hierarchy, absent with OBJ and STL( exported from ChimeraX anyway) so this is promising. Now to find a converter. >>>>> >>>>> The GLTF export link is informative, it may help further refine my approach. Interestingly, the molecule you’ve chosen for demo purposes appears to be the one, or a variant thereof, I’ve been testing with! >>>>> >>>>> Thanks again, >>>>> >>>>> Byrne >>>>> >>>>> >>>>>> On Dec 2, 2021, at 12:30 PM, Tom Goddard <goddard(a)sonic.net <mailto:goddard@sonic.net>> wrote: >>>>>> >>>>>> Hi Byrne, >>>>>> >>>>>> We have long been interested in adding Collada format export of scenes from ChimeraX. Here is the feature request for that >>>>>> >>>>>> https://www.rbvi.ucsf.edu/trac/ChimeraX/ticket/485 <https://www.rbvi.ucsf.edu/trac/ChimeraX/ticket/485> >>>>>> >>>>>> But our scene export in ChimeraX has focused on GLTF format, as that has been the most requested. Here is an example showing GLTF export from ChimeraX (including texture colors). >>>>>> >>>>>> https://www.rbvi.ucsf.edu/chimerax/data/texture-may2021/export_3d.html <https://www.rbvi.ucsf.edu/chimerax/data/texture-may2021/export_3d.html> >>>>>> >>>>>> ChimeraX also exports OBJ, STL, X3D, VTK as shown in the save command docs >>>>>> >>>>>> https://rbvi.ucsf.edu/chimerax/docs/user/commands/save.html#formats <https://rbvi.ucsf.edu/chimerax/docs/user/commands/save.html#formats> >>>>>> >>>>>> Can you make use of GLTF files? If not, a quick solution might be to convert ChimeraX GLTF files to Collada with third-party software. >>>>>> >>>>>> Tom >>>>>> >>>>>>> On Dec 2, 2021, at 10:41 AM, Byrne Pedit via Chimera-users <chimera-users(a)cgl.ucsf.edu <mailto:chimera-users@cgl.ucsf.edu>> wrote: >>>>>>> >>>>>>> ChimeraX is awesome and definitely superior to the original but for the inability to export as .dae (Collada). Is that possibly on the to-do list? This is important for those of us (just me?) writing interactive molecular apps for devices. It is the only satisfactory path I’ve found between a PDB file and SCNNodes/Scenes in iOS. (See the iOS app ‘BioMole’, free, if interested in an application.) >>>>>>> _______________________________________________ >>>>>>> Chimera-users mailing list: Chimera-users(a)cgl.ucsf.edu <mailto:Chimera-users@cgl.ucsf.edu> >>>>>>> Manage subscription: https://plato.cgl.ucsf.edu/mailman/listinfo/chimera-users <https://plato.cgl.ucsf.edu/mailman/listinfo/chimera-users> >>>>>>> >>>>>> >>>>> >>>> >>> >> >

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Selection command for atoms in different models
by Woodbrey Anne 14 Dec '21

14 Dec '21

Hi, Is there a way to select residues from 2 different models using a single line of command? For example, I want to select residues 230 and 260 of Model 0 and residues 232 and 262 of Model 1. I then want to display the side chains, color magenta, then color by heteroatom. This is what my current (annoying) workflow is: select #0:230,260 Actions --> Color --> Magenta Actions --> Color --> By heteroatom select #1:232,262 Actions --> Color --> Magenta Actions --> Color --> By heteroatom I know I can do the following instead: disp #0:230,260 color magenta #0:230,260 color byhet #0:230,260 Repeat for #1:232,262 ...but it doesn't really save any time. I want to select all 4 residues at once without having to ctrl + shift + click on them all. Please tell me there's a way! Thank you, Annie

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calculating radius of gyration
by Elaine Meng 14 Dec '21

14 Dec '21

> On Dec 14, 2021, at 11:10 AM, Simon.Chapman <simon.chapman(a)open.ac.uk> wrote: > > Hello again Elaine. All going very well with Chimera, and I've introduced the software to some more of mt students. > > But, is there a way to plot radius of gyration from the simualtion data? I would have thought somehow the RMSD over time should allow that? > > Best wishes Hi Simon, Thanks for introducing others to Chimera! I'm not the expert on this topic, so I had to consult with others to answer this question. Just as a reminder, it's recommended to send questions to chimera-users(a)cgl.ucsf.edu (CC'd here) unless what you are sending needs to remain private. I don't know everything (surprise!) or I might not understand your question as well as somebody else does. RMSD compares different sets of coordinates, so I don't think that gets you anything like the radius of gyration of a single set of coordinates. There are some scripts to calculate radius of gyration on the Chimera Python Scripts page: <https://plato.cgl.ucsf.edu/trac/chimera/wiki/Scripts> 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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