June 2025 - ChimeraX-users - RBVI Mailing Lists

Q-Score not shown in output file
by Thu Nguyen 05 Jun '25

05 Jun '25

Hi, I am trying to calculate the Q-score of this density map and structure pair using the Q-Score plugin <https://cxtoolshed.rbvi.ucsf.edu/apps/chimeraxqscore> in ChimeraX and save the score to the output file. I loaded the 2 files to ChimeraX and used this command "qscore #2 toVolume #1 useGui false pointsPerShell 8 shellRadiusStep 0.100 maxShellRadius 2.00 referenceGaussianSigma 0.60 logDetails false outputFile /Desktop/q_score.txt" However, the output file is empty and I got the error message in ChimeraX. When I removed the outputFile option, it worked as normal and gave me the average score of .32. Do you know why it happened like this and what I should do to fix it? Thank you very much. Best regards, Thu

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Select all truncated amino acids in model (though ISOLDE?)
by Vorländer,Matthias Kopano 05 Jun '25

05 Jun '25

Hi everyone, Is it possible to create a selector or python script to identify/match all truncated amino acids in a model? If not possible directly in ChimeraX, could ISOLDE offer a solution through matching to residue template “TRUNC_CB”? Thanks in advance, Matthias

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Using measure area command
by jillian.baker＠som.umaryland.edu 04 Jun '25

04 Jun '25

Dear ChimeraX community, I am trying to use the 'measure area' command to measure the area using three atoms (essentially trying to calculate the area of a triangle). I have come up with the script of "measure area #2/b:44@o,97@ca,57@hz3" with 2 being model ID, b being the chain, and then the numbers being residues and the atoms are followed by the "@" symbol. I don't quite get an error here, but I get back "No surfaces specified." I can't seem to figure out away to specify a surface or use a different command to calculate the between these three points. Any help with this would be greatly appreciated. Thanks, Jill

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Align molecule to axes
by Alexander Lee 03 Jun '25

03 Jun '25

Dear ChimeraX community, I have an optimized benzene ring that's floating in space. Is there a way to align that ring to one of the axes' planes so that 2 of the 3 cartesian coordinates read 0,0? Ex: C1 0.00 0.00 z1 C2 0.00 0.00 z2 C3 0.00 0.00 z3 etc Regards, Alex

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Shading from N-terminus to C-terminus?
by Nick Matzke 02 Jun '25

02 Jun '25

Dear ChimeraX list, Thanks so much for this amazing software! I have a kind of obscure question for which I could not find an answer on Google. I've got the FliPQR-FlhB structure, from here: https://www.rcsb.org/structure/6S3L This has 5 copies FliP 1 copy FliR 4 copies FliQ 1 copy FlhB I opened it and am using ribbon view. I've colored the chains by protein type with these commands: color /a,b,c,d,e purple color /f red color /g,h,i,j green color /k yellow Now, I'd like to have each chain shaded from N-terminus to C-terminus, e.g. dark red to light red, or something like that. (I see the rainbow option, but this creates a very complex view if all 11 chains are each an roygbiv rainbow.) Almost as good, is there a way to easily label the N-terminus and C-terminus of each chain? Any suggestions! Thanks so much, Cheers, Nick

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ChimeraX support: Alphafold contacts
by Anthony Newcombe 02 Jun '25

02 Jun '25

Hello I have a commercial license of ChimeraX, I have a question you may be able to help with I have used Structure prediction > Alphafold to predict structures and interactions between 2 proteins and this returned the best_model.pdb But I would like to identify contacts within 8 angstroms, as shown in the Youtube video: https://www.youtube.com/watch?v=TMcjEecFHaI&list=WL&index=26'm typing the command: alphafold contacts /A to /B distance 8 But receive the error: 'Structure best_model.pdb #1 does not have PAE data opened' Do I need to open something? If you can help that would be much appreciated Many thanks Tony Anthony Newcombe PhD Applied Biopharm Consulting Ltd Cork, Ireland http://www.appliedbiopharm.com<http://www.appliedbiopharm.com/> IE: +353 (0)87 3634486 [cid:image001.png@01DBD2E1.AD97E890] Applied Biopharm Consulting Limited is a company located in the Republic of Ireland Reg. No: 747251, VAT No: IE4188817RH. Registered office: Brook Lodge, Lisnacunna, Ballinascarthy, Clonakilty, Cork, Ireland P85 C832. This message is confidential and intended solely for the recipient(s). If you are not the intended recipient, any use, disclosure, copying or distribution of this message or its attachments is strictly prohibited. Please notify the sender immediately by replying to this email and delete the message, its attachments and any copies.

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Comparing Maps
by Abhilash Padavannil 02 Jun '25

02 Jun '25

Hello, I have five different cryoEM maps coming from similar samples. The maps are at different resolutions. I want to compare the density at the region of interest across these maps. How do I normalize the maps say to the first map to make accurate analysis. I know I could scale them using vop scale, but I am wondering which of the parameters I should use. Thanks in advance for your suggestions. Abhilash.

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