- ChimeraX-users - RBVI Mailing Lists

bond: merging two models within new model
by Enrico Martinez 17 Jul '23

17 Jul '23

Dear Chimera-X users ! I need to fuse two models in the entire construction. Precisely having a water soluble domain with a linker in the first model #1 as well as transmembrane alpha helix segment in the #2 I load the both in chimera-x and then use the bond command with the aim to create a peptide bond between the last residue of the #1 and the first residue of the #2. Here is my command: # select the last residue from the core and the first residue from the TM helix; build join peptide #1:182@C #2:1@N move large The problem is that on the text step I will need to add the membrane in the TM part, but the orientation of the created construction is not optimal. How could I easily modify the mutual orientation between #1 and #2 ? I join the both initial pdbs to this message, in order that my model could be checked :-) Many thanks in advance Enrico

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Re: [Chimera-users] Chimera-X inteprhase of the AlphaFold
by Tom Goddard 17 Jul '23

17 Jul '23

Hi Enrico, The ChimeraX AlphaFold interface does not allow specifying your own structure template. But the ColabFold web server does allow this https://colab.research.google.com/github/sokrypton/ColabFold/blob/main/Alph… using "template mode: custom" on that web page and follow instructions they list on that page for using custom templates https://colab.research.google.com/github/sokrypton/ColabFold/blob/main/Alph… I have tried custom templates with AlphaFold in the past and it has never changed the predicted structure. AlphaFold only uses the template as a first guess at the structure then it does multiple rounds (by default 3 recycles) of creating new models. If AlphaFold is pretty confident about a different conformation than the template it simply replaces the starting structure with the conformation it prefers. Possibly if AlphaFold has low confidence in a prediction a template could bias it to get a different conformation but I've never seen that happen. This is a basic limitation of AlphaFold that it is not designed to optimize an existing structure. The input that dominates the calculation is the sequence and the deep sequence alignment that it computes, not template structures. Possibly AlphaFold could be prodded to predict different conformations by changing the deep sequence alignment to include just the sequences known to fold in the desired conformation and excluding sequences known to fold in a different conformation. Tom > On Jul 13, 2023, at 3:43 AM, Enrico Martinez via Chimera-users <chimera-users(a)cgl.ucsf.edu> wrote: > > Dear Chimera-X users! > > In parallel to the modeller, I am trying to use the Alpha fold > interface with the aim to full model starting from the sequence using > template. > > The problem is that I can not define manually which template I would > like to use for each prediction so the interphase takes its > automatically based on the input sequence and the final prediction is > not very precise. Would it be possible rather to specify a specific > pdb ID additionally to a given sequence ? > > Many thanks in advance > > Enrico > _______________________________________________ > Chimera-users mailing list -- chimera-users(a)cgl.ucsf.edu > To unsubscribe send an email to chimera-users-leave(a)cgl.ucsf.edu > Archives: https://mail.cgl.ucsf.edu/mailman/archives/list/chimera-users@cgl.ucsf.edu/ >

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ChimeraX in Debian v-12
by Stephen P. Molnar 15 Jul '23

15 Jul '23

I would lie to install ChimaeraX on my Debian v-12 desktop. However, he installer requires libffl7 which is not available. Please advise. Thais in advance -- Stephen P. Molnar, Ph.D. https://insilicochemistry.net (614)312-7528 (c) Skype: smolnar1

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Re: [Chimera-users] hiding a model slowly in ChimeraX
by Elaine Meng 14 Jul '23

14 Jul '23

Hi Andy! I added "in ChimeraX" to the subject line to make it more obvious to the Chimera users. We recommend sending ChimeraX questions to chimerax-users(a)cgl.ucsf.edu (CC'd here so you don't need to re-send) instead of chimera-users so that people don't get confused between the two programs - thanks! Here are some thoughts on how to do it in ChimeraX: (1) is anything in the view moving (rotation, translation, conformational change) while this model fades? If not, you can simply use "crossfade" or if you are recording a movie anyway, better to use "movie crossfade", in the script between where the model is shown and where it is hidden. <https://rbvi.ucsf.edu/chimerax/docs/user/commands/crossfade.html> <https://rbvi.ucsf.edu/chimerax/docs/user/commands/movie.html#crossfade> (2) if you want motions of the view or of individual models at the same time as the fading, then crossfade won't work. Instead you have to do something fancier. Instead of hiding the model you could try gradually changing its transparency from 0% to 100% over some number of frames. This requires combining the "transparency" command with a "perframe" command to iterate over different transparency levels, since you don't want to have to put in 100 (or more) transparency commands. For example, if the model is currently completely opaque (0% transparent) then you can make it completely transparent (100% transparent) over 240 image frames with something like roll y 0.1 perframe 'transparency #7 $1 target abcsp' range 0,100 frames 240; wait 240; ~perframe The "roll" command is only included above as an example so you can see how this fading works during motions. See the help pages for "transparency" and "perframe": <https://rbvi.ucsf.edu/chimerax/docs/user/commands/transparency.html> However, it will require experimentation with how you specify the other commands for the motion (view, turn, roll, zoom, coordset, etc.) in your command script to make this fading happen at the same time as those motions. Even experts don't get their movie scripts right on the first try; I usually have to change and re-run my script several times. I don't even add the movie-recording commands until after I get all the motions and display changes right. Carrying on from the example above, you can stop the roll and make the model opaque again with something like stop transparency #7 0 target abcsp You stay safe too! I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco > On Jul 14, 2023, at 3:09 PM, Sen, Anindito via Chimera-users <chimera-users(a)cgl.ucsf.edu> wrote: > > Dear Chimera X team, > > Is there a way I can hide one of the models in a ChimeraX session slowly (like fading it off) while making a movie. > > typically I use > > hide #7 model > > Stay safe & Regards > > Anindito Sen. Ph.D > > Microscopy and Imaging Center > Texas A&M University > 301 Old Main Dr > College Station, TX 77843-2257 > > Office: ILSB Room 1133 > Tel. 979-458-9881 > fax: 979-847-8933 > http://microscopy.tamu.edu

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getting RSCC validation scores
by Das, Abhinaba 14 Jul '23

14 Jul '23

Hi ChimeraX community: I’m trying to get real space correlation coefficient value of map-model fit as done in this paper from DiMaio’s group https://elifesciences.org/articles/17219 (Table 2, RSCC validation map column). It is possible to do so in Chimera but I’m not sure how. Although the alternative might be the Map-Q & Q-score plugin in chimera (or Model-Map Q score in ChimeraX) from Greg Pintilie which “uses a real-space correlation approach to assess the resolvability of each model atom in the map” (-http://doi.org/10.1038/s41592-020-01051-w), I would like to get the RSCC values. Is it possible to obtain those values? Thanks in advance for any advice. -abhi

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installation problem with MacOS
by Fabienne Charbit-Henrion 13 Jul '23

13 Jul '23

Hello! I tried to install Chimera X on my Macbook (2016), with MacOS Sierra, but i have this message: [image: image.png][image: image.jpeg] "Image damaged" is there an older release I should install? I tried 1.6 and 1.5 i SO hope it will work!! thanks a lot for your help Fabienne CHARBIT-HENRION

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Re: [Chimera-users] Chimera-X inteprhase of the AlphaFold
by Elaine Meng 13 Jul '23

13 Jul '23

Hello, Since this is a ChimeraX question it should go to chimerax-users(a)cgl.ucsf.edu instead of chimera-users(a)cgl.ucsf.edu (we don't want to confuse the Chimera users). But since the answer is short I will try to give it now: sorry, there is no ChimeraX option to control which template(s) the alphafold calculation uses. There is an option "Use PDB templates when predicting structures" but that is only to control whether it uses any templates or not. Default is off, do not use any templates. <https://rbvi.ucsf.edu/chimerax/docs/user/tools/alphafold.html#options> I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco > On Jul 13, 2023, at 3:43 AM, Enrico Martinez via Chimera-users <chimera-users(a)cgl.ucsf.edu> wrote: > > Dear Chimera-X users! > > In parallel to the modeller, I am trying to use the Alpha fold > interface with the aim to full model starting from the sequence using > template. > > The problem is that I can not define manually which template I would > like to use for each prediction so the interphase takes its > automatically based on the input sequence and the final prediction is > not very precise. Would it be possible rather to specify a specific > pdb ID additionally to a given sequence ? > > Many thanks in advance >

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Modeler interphase of the Chimera-x
by Enrico Martinez 13 Jul '23

13 Jul '23

Dear Chimera-X users ! I am trying to use the Modeller interphase of the Chimera-X, with the aim to model missed segments from the input PDB structure. I have very basic questions: 1) In the top, there is a Sequence Alignment dialog box but I don't understand how to provide the alignment there. Should it be the alignment of the sequence of the target pdb (template) ? If so, how could it be obtained supposing that I have i) a pdb with missing fragments as well as ii) the full sequence. Many thanks in advance Enrico

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PDB coordinates missing--how to add residues to N-terminus
by stevensb＠ufl.edu 12 Jul '23

12 Jul '23

The first few N-terminus residues of a seq are grayed out in the PDB sequence viewer and are missing in the PDB chain. It is even possible for ChimeraX to make the peptide bonds to glue on the missing residues in the helix in accurate XYZ positions tacked on at N-terminus without resorting to generating an Alphafold model? I am also thinking ISOLDE won't work.

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Problem using a python script to run chimeraX (installation?)
by Collignon, Bar /FR 12 Jul '23

12 Jul '23

Hello, I am picking up an old code that used chimera and updating it to use ChimeraX. Our code writes a python script file that looks like : import chimera from chimera import runCommand runCommand("open ../4ZKC_H_reduce.pdb") runCommand("swapaa LYS #0:11.B&:LYS lib dynameomics") runCommand("swapaa TRP #0:51.B&:TRP lib dynameomics") runCommand("write #0 ../4ZKC_H_reduce.pdb") and executes chimera --nogui --nostatus --script python_script.py I installed ChimeraX on Ubuntu 22.01 with the .deb from your website and "sudo apt install chimerax.deb" When i execute ChimeraX with my script, i get : available bundle cache has not been initialized yet Executing: runscript chim_4ZKC_H_reduce.py Traceback (most recent call last): File "chim_4ZKC_H_reduce.py", line 2, in <module> from chimera import runCommand ModuleNotFoundError: No module named 'chimera' Traceback (most recent call last): File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/scripting.py", line 84, in open_python_script _exec_python(session, code, argv) File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/scripting.py", line 61, in _exec_python exec(code, sandbox.__dict__) File "chim_4ZKC_H_reduce.py", line 2, in <module> from chimera import runCommand ModuleNotFoundError: No module named 'chimera' During handling of the above exception, another exception occurred: Traceback (most recent call last): File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/__main__.py", line 747, in init run(sess, 'runscript %s' % script) File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/commands/run.py", line 38, in run results = command.run(text, log=log, return_json=return_json) File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/commands/cli.py", line 2897, in run result = ci.function(session, **kw_args) File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/commands/runscript.py", line 38, in runscript open_python_script(session, open(script_file, 'rb'), script_file, argv=argv) File "/usr/lib/ucsf-chimerax/lib/python3.9/site-packages/chimerax/core/scripting.py", line 90, in open_python_script raise UserError('Error opening python file %s' % stream.name) chimerax.core.errors.UserError: Error opening python file chim_4ZKC_H_reduce.py I tried installing chimera using pip but it installs Chimera (the one in python 2.7) and crashes during the installation. Any ideas on how to fix this? Did i do something wrong somewhere? Thanks you very much for your help, Bar Collignon

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