March 2021 - ChimeraX-users - RBVI Mailing Lists

Global Diffusion Tensor Models
by Gupta, Arun 17 Mar '21

17 Mar '21

Dear ChimeraX team, I am interested in generating Global diffusion tensor geometry models such as Prolate, Ellipsoid, Oblate or Sphere with overlaid protein PDB or structure of my interest. (As shown in attached pic). I am using diffusion tensor prediction module provided in ROTDIF software (http://gandalf.umd.edu/FushmanLab/pdsw.html) to generate an ellipsoid diffusion tensor of a protein molecule of my interest. Is it possible that I can use ROTDIF generated output (Which is in Pymol output format, please find attached ) to open in ChimeraX with my protein PDB, to render such representative figure ? Thanks!!! Arun Arun Gupta PhD, MRSC Research Fellow Challis & Lewandowski Group Chemistry Department University of Warwick Gibbet Hill Road Coventry CV4 7AL United Kingdom

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Blast Protein not working
by Moradkhan, Tiglath A 16 Mar '21

16 Mar '21

Hi I found what the problem is. I forgot to blast my sequence. But when I run the blastprotein tool I get the following error: ValueError: not enough values to unpack (expected 2, got 1) File "C:\Program Files\ChimeraX 1.1\bin\lib\site-packages\chimerax\blastprotein\pdbinfo.py", line 206, in fetch_info entry, auth_cid = pcid.split('_') See log for complete Python traceback. I would be very grateful for your help. Thank you Tiglath

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Question about modelling
by Moradkhan, Tiglath A 16 Mar '21

16 Mar '21

Hi For some reason when I try to model using ChimeraX it cuts off the first two amino acid residues of the N-terminus. I'm trying to model dimeric sea otter Apo A-I using the pdb structure of 3R2P as a template. The sea otter sequence is: DEPQSPWDRVKDLATVYVDVVKDGGRDYVAQFEASA LGKQLNLKLLDNWDSLSSTVTKLREQIGPVTQEFWDNLEKETEALRQEMSKDLEEVKQKV QPYLDEFQKKWHEEVELYRQKVAPLGAELREGARQKLQELQEKLTPLGEELRDRARTHVD ALRAQLAPYSDQLRERLASRLQALK But the template does not contain the first two amino acid residues. When I model the sea otter protein, it doesn't include the first two amino acids. I'm not sure why it's doing that. I would be very grateful for your help. Thanks Tiglath

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radial coloring cryo map
by Moustafa, Ibrahim M. 15 Mar '21

15 Mar '21

Dear all, I am trying to color a cryoem map radially in ChimeraX (to get something similar to surface color by radius in chimera). I used the following comand: color radial #model However, the map is colored from one side to the other instead of radial coloring starting from the center. I tried to specify the center of the screen as 0,0,0 but that did not help. What is the correct command/options to do radial coloring in ChimeraX? Thanks for help, Ibrahim

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pause/wait read user input in chimerax script
by andrew 13 Mar '21

13 Mar '21

Greetings, I would be grateful for help with a script. I made a .cxc script. Now, I would like to show somebody the steps, one by one as in I download this [return] I select that [return] colour these [return] but I cannot see how to insert a pause/wait or something that waits on keyboard input. I did try to insert a "runscript" and put some lines in a python script that reads from the keyboard, but it looks as if chimerax has redirected the script's stdin. I have a feeling, that if I knew what I was doing, I could put another line in the python script "import chimerax.core" and read until the next newline from the command line. Is there a way to pause after each line in a script ? Many thanks for any advice.

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Placement of markers after translation
by Helge Paternoga 09 Mar '21

09 Mar '21

Dear ChimeraX team, I have a question regarding the placement of markers. I am currently trying to extract densities from cryo-EM maps for figure preparation. Therefore, I am using markers to colour any density that is not part of what I want to extract and then split the map accordingly. I noticed that when I translate a markerset, e. g. by using "view position" with "sameAsModels", new markers are not placed at the cursor position, but instead are transformed according to the translation of the whole markerset. Therefore, to move markers, I have to use the "move marker" command on each marker separately. I would like to know if this behaviour is intented and if it can be switched somehow to place markers at the cursorposition even after translation of the markerset. Ultimately, I would like to re-use defined markersets for extracting (or "cleaning") the same invariant components of my maps. But the current behaviour makes it nearly impossible to add new markers for touch-ups after opening and aligning a markerset. Best, Helge

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Volumes
by Colton Carlson 09 Mar '21

09 Mar '21

Hello, I am just wondering if ChimeraX has added the ability to colour surfaces based on the values of a different surface? That is, input 2 cube files, then colour one cube file based on the values of the other. It is available in the other version of chimera, but the only information I could find on this was from 2018 and said it was not yet implemented in ChimeraX. Thanks a bunch! Colton

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Re: [chimerax-users] ChimeraX - defattr Problems
by Elaine Meng 08 Mar '21

08 Mar '21

Hi Harsh, Sorry, I don't know the answer, so I'm CC'ing the chimerax-users(a)cgl.ucsf.edu list. In general, please use the chimerax-users(a)cgl.ucsf.edu address to ask us questions unless your message contains private data. It allows others to answer or to learn from the answers, serves as a record of our service, and is searchable later. Also, when you get a traceback, it is sometimes better (than sending mail directly) to use the menu: Help... Report a Bug and attach any files needed to reproduce the problem, as well as including a short description of what you did and your e-mail address if you want feedback. That will automatically send us information about platform, version, etc. Thanks, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco > On Mar 6, 2021, at 7:25 PM, Harsh Srivastava <hrs4853(a)rit.edu> wrote: > > Hello Dr. Meng, > > I hope this message finds you well. I am receiving the following error when attempting to load an external attribute file into ChimeraX using the defattr command as follows: > > defattr /Users/harsh/Downloads/attfile.defattr > > 1.1.1.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/chimerax/atomic/attr_registration.py", line 90, in register > type_str(prev_attr_type), type_str(attr_type))) > chimerax.atomic.attr_registration.RegistrationConflict: Registration of attr 'deltaKL' with Residue by defattr command conflicts with previous registration by defattr command due to differing value types (int vs. float) > > chimerax.atomic.attr_registration.RegistrationConflict: Registration of attr 'deltaKL' with Residue by defattr command conflicts with previous registration by defattr command due to differing value types (int vs. float) > > File "/Applications/ChimeraX-1.1.1.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/chimerax/atomic/attr_registration.py", line 90, in register > type_str(prev_attr_type), type_str(attr_type))) > > Below is an excerpt of the attribute file following the rules outlined on the web documentation. It might not be apparent on email, but the format of the values is (tab)(residue)(tab)(value). > > attribute: deltaKL > recipient: residues > :1 0.23 > :2 0.23 > :3 0.23 > :4 0.27 > :5 0.19 > :6 0.06 > :7 0.1 > :8 0.46 > :9 -0.44 > :10 0.15 > :11 0.32 > :12 0.05 > :13 -0.6 > :14 -0.4 > :15 -0.35 > :16 0.2 > :17 0.14 > > I receive the same error consistently where ChimeraX tells me there is a conflict when registering the attribute despite having never registered a deltaKL attribute to the structure. > > Would you kindly be able to advise? > > Kindly, > Harsh > -- > Harsh Srivastava > Rochester Institute of Technology > Bioinformatics and Computational Biology > hrs4853(a)rit.edu > >

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Getting rid of a gap in a helix ribbon
by Luca Pellegrini 08 Mar '21

08 Mar '21

Hi, The cartoon drawing of one helix in my structure has a gap in the middle, where it is drawn as a coil. I would like to draw the whole helix as a continuous ribbon. If I select the two consecutive residues at the gap and type: 'setattr sel res ss_type 1' the gap remains. So it looks like the residues at the gap are already helical, as the C-end and N-end residues of two consecutive helices. This looks trivial to fix but I can’t figure it out at the moment… Thanks for your help. Best wishes, Luca Luca Pellegrini, PhD Department of Biochemistry University of Cambridge Cambridge CB2 1GA UK

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Displaying multiple sequences during alignment
by Y. Mutum 08 Mar '21

08 Mar '21

Hi I have a very quick query. I opened up 3 models - 3cx5, 2qjp and 1zrt in ChimeraX. I was thinking of aligning on one of the chains and looking at the global-sequence-alignment. >>> match #3/C #2/A to #1/C showAlignment true The sequence alignment opens up as pairwise sequence alignement, in 2 separate windows for each of the 2 pairs. Picture attached. Rather, is there a way to get all 3 sequences aligned together, not separately? I tried looking up at other options, but I think I am missing out something somewhere. Thanks Yaikhomba

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ChimeraX-users March 2021