- Chimera-users - RBVI Mailing Lists

ChimeraX in no-gui mode: visualisation of protein-ligand interactions
by Enrico Martinez 15 Jan '22

15 Jan '22

Dear Chimera's users! First I wish Happy New Year to everyone! I am just switching from Chimera to ChimeraX that I am going to use in no-gui (batch) mode to prepare screen shots of protein-ligand interactions based on the protein-ligand docking poses. Basically I am loading a pdb file of the complex (consisted of protein and ligand in multi-model format) from the terminal of my macOSX. I have a template for a batch file created in the bash script on the fly, that I used 2 years ago with an early version of ChimeraX. # a batch file for chimeraX printf "open ${pdb} view; zoom 1.0; turn x 90; turn z -80; wait # options for appearance preset 'overall look' publication # set bg powder blue set silhouettes t; set silhouetteColor indigo; set silhouetteDepthJump 0.02 # make info of the screen 2dlab create title text \"${pdb_name}\" color red font gothic xpos .04 ypos .92 size 35 # options for light light depthcuestart .4 depthcueend .8; lighting full intensity 1.4 shadows true qualityOfShadows finer save image ${structure}/${pdb_name}.png format png width 800 height 600 supersample 4 transparentBackground false wait exit" > chimeraX.${pdb_name}.cxc" then I use it directly in terminal as chimerax-daily chimeraX.${pdb_name}.cxc" may you suggest some commands that I may introduce into my batch file to 1) delete all models from the multi-model pdb file with the exemption of the first model. 2) switch from cartoon to surface representation of the protein 3) visualize protein-ligand non-covalent interactions in the current model Yours with thanks Enrico

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Re: [Chimera-users] Question on pdb to mrc
by Elaine Meng 14 Jan '22

14 Jan '22

> On Jan 13, 2022, at 6:54 PM, Guan, Lan <Lan.Guan(a)ttuhsc.edu> wrote: > > Dear Elaine, > > I try to generate a reference model from crystal structure pdb file for cryo-EM particle alignment. > > I can get the map by “molmap #1 6”; #1 = my pdb file id; 6 = resolution I want to get in the output model. > > After imported into cryosparc, I can not use it. Error “ Cubic volumes only”. My question is how to change this Molmap output into a cubic volumes in Chimera? > I would appreciate for your input. > > Lan Hi Lan, (CC'ing chimera-users(a)cgl.ucsf.edu which is the address recommended for asking questions since others may have better answers) I don't know what cryosparc means by "cubic volumes only". My only guess is that maybe you did not save the molmap map correctly. The molmap command should make a new model which is the map, and then you can save the map with the Volume Viewer tool's File menu, or with the "volume" command. Saving data: <https://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/savemodel.html> Volume Viewer menu (File... Save map as...) <https://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/volumeviewer/vol…> volume command saving options <https://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/volume.html#output> Or, maybe cryosparc does not read any of the map formats that Chimera can write (listed in the link above). 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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Re: [Chimera-users] Protonating Histidine Residues using Chimera
by Elaine Meng 13 Jan '22

13 Jan '22

> On Jan 13, 2022, at 10:54 AM, Joshi, Keya <keyajoshi1996(a)ku.edu> wrote: > > Hello Prof. Meng, > Hope you are doing well and staying safe. My name is Keya Joshi. I am a second year PhD student in the department of Computational Biology at the University of Kansas. I am trying to use Chimera to protonate Histidine residue 816 in chain B. But I have no idea about how to do this using Chimera. > Can you please help me with this? > > With Regards > Keya Joshi Hi Keya, I hope you are well, too! (CC-ing the chimera-users(a)cgl.ucsf.edu address which is recommended for asking Chimera questions unless you are sending data that needs to remain private) In the structure that you sent, histidine 816 in chain B is already protonated (already has hydrogens). However, it is protonated to the neutral state. Maybe you meant you wanted one more hydrogen to make it the positively charged state. Two ideas: (1) You can just use the AddH tool (menu: Tools... Structure Editing... AddH) or "addh" command to add hydrogens to the whole protein. See help for information about the options: <https://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/addh/addh.html> <https://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/addh.html> On the PDB file that you sent, the default options of AddH (= simply using command "addh" without any other options) do add a hydrogen to 816 in chain B to put it in the positively charged state, but it also adds lots of other hydrogens including on carbons and on all of the other residues. I don't know if that is a problem for you, or whether it is an improvement on the original structure. Of course you can delete some hydrogens afterward, but it depends what you want. (2) To just add one hydrogen to that sidechain nitrogen, instead use Build Structure (menu: Tools... Structure Editing... Build Structure), and in that tool change from "Start Structure" to "Modify Structure". Select (Ctrl-click on) the nitrogen of His 816 that needs the hydrogen. Selection is shown with a green outline on that atom. Then in the tool, you want that selected atom to be N (stay the same element) but with 3 bonds and trigonal geometry as shown in the screenshot. Also as shown in the screenshot, choose the option to leave the residue name unchanged. Then click Apply to add that one hydrogen. ... after I click Apply it looks like this: about selection: <https://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/selection.html> Build Structure tool: <https://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/editing/editing.…> You can find Chimera features using Chimera menu: Help... Search Documentation, e.g. to search for "hydrogens" or "building" Our newer program ChimeraX also has an "addh" command. 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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Autodock Vina plugin
by Enrico Martinez 12 Jan '22

12 Jan '22

Dear Chimera Users, First Happy New Year to you and your families! I am trying to perform protein-ligand docking using UCSF Chimera 1.16v installed on my iMAC Big Sur. Using the pdb of the receptor and mol2 of the ligand (that I have already tested with VINA 1.2.3!) I got the following error: Model 1 (receptor.pdb) appears to be a protein without secondary structure assignments. Automatically computing assignments using 'ksdssp' and parameter values: energy cutoff -0.5 minimum helix length 3 minimum strand length 3 Use command 'help ksdssp' for more information. No SEQRES records for receptor.pdb (#1) chain A; guessing terminii instead Chain-initial residues that are actual N terminii: #1 SER 1.A Chain-initial residues that are not actual N terminii: Chain-final residues that are actual C terminii: Chain-final residues that are not actual C terminii: #1 THR 304.A 278 hydrogen bonds Removing spurious proton from 'C' of #1 THR 304.A Hydrogens added Wrote test.receptor.pdb into /Users/gleb/Desktop/docking_tuto adding gasteiger charges to peptide Traceback (most recent call last): File "/Applications/Chimera.app/Contents/Resources/share/vina/ws.py", line 395, in prepareReceptor execfile(scriptPath, d) File "/Applications/Chimera.app/Contents/Resources/lib/python2.7/site-packages/AutoDockTools/Utilities24/prepare_receptor4.py", line 172, in <module> delete_single_nonstd_residues=delete_single_nonstd_residues) File "/Applications/Chimera.app/Contents/Resources/lib/python2.7/site-packages/AutoDockTools/MoleculePreparation.py", line 533, in __init__ version=version, delete_single_nonstd_residues=delete_single_nonstd_residues) File "/Applications/Chimera.app/Contents/Resources/lib/python2.7/site-packages/AutoDockTools/MoleculePreparation.py", line 140, in __init__ self.addCharges(mol, charges_to_add) File "/Applications/Chimera.app/Contents/Resources/lib/python2.7/site-packages/AutoDockTools/MoleculePreparation.py", line 226, in addCharges chargeCalculator.addCharges(mol.allAtoms) File "/Applications/Chimera.app/Contents/Resources/lib/python2.7/site-packages/MolKit/chargeCalculator.py", line 80, in addCharges babel.assignHybridization(atoms) File "/Applications/Chimera.app/Contents/Resources/lib/python2.7/site-packages/PyBabel/atomTypes.py", line 127, in assignHybridization a.babel_atomic_number = self.get_atomic_number(a.babel_type) File "/Applications/Chimera.app/Contents/Resources/lib/python2.7/site-packages/PyBabel/atomTypes.py", line 103, in get_atomic_number (name,_name) ) ValueError: Could not find atomic number for Hn Hn Receptor preparation for AutoDock Vina failed; please look in Reply Log to see error messages.cannot prepare receptor for AutoDock Vina; please look in Reply Log and/or run Chimera with --debug flag to see errors. So here are my questions: 1) May this error be related to the version of OSX installed on my imac (I can not run MGL tools on the Big Sur for instance) ?? 2) Alternatively may I use the ADT scripts integrated in the Chimera like prepare_receptor4.py for my scripting purposes (outside of the UCSF Chimera) on the same iMAC machine ? Many thanks in advance! Cheers Enrico

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Error on installation on a student's computer
by Kenward Vaughan 11 Jan '22

11 Jan '22

Hello all, As usual I have my students installing Chimera as part of their continuing adventure in organic chemistry, but have one of them reporting an error on attempted startup after installation. So far I have little information (we haven't started classes yet--next week--but she has sent the error message obtained. It is apparently on Windows. I suggested that she try starting from the command line to do the debug run, but this is from a distance at this time and I don't know how savvy she is with such stuff. Is there enough information in just the number noted by this message for someone to know what might be happening with her setup? Many thanks, and cheers! Kenward -- In a completely rational society, the best of us would aspire to be _teachers_ and the rest of us would have to settle for something less, because passing civilization along from one generation to the next ought to be the highest honor and the highest responsibility anyone could have. - Lee Iacocca Any fool can know. The point is to understand. - Albert Einstein

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Problem with the app
by Nicola De Trino 11 Jan '22

11 Jan '22

I have download the chimera-1.16-win64.exe <https://www.cgl.ucsf.edu/chimera/cgi-bin/secure/chimera-get.py?file=win64/c…> for Windows 64 bit. I have installed but when i try to launch the program, it appears an error message : *chimera exited abnormally; the exit code was: -1073731819. * I try to install again the program but same result. I don't know how to fix the problem. <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_cam…> Mail priva di virus. www.avg.com <http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_cam…> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> -- ------------------------ Indirizzo istituzionale di posta elettronica degli studenti e dei laureati dell'Università degli Studi di TorinoOfficial University of Turin email address for students and graduates

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Convenient way to move 2D labels around
by Prathvi Singh 09 Jan '22

09 Jan '22

Hi Elaine, Is there a convenient way (a keyboard or mouse shortcut) to move 2D labels around once the 2D labels window has been closed? Thanks -- Prathvi Singh, Research Fellow, Department of Biological Sciences & Bioengineering, Indian Institute of Technology, Kanpur-208016

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Model placement side by side
by George Tzotzos 07 Jan '22

07 Jan '22

Hi, Having superimposed 4 structures using MatchMaker, is there a way to view the aligned structures in a window grid? Moving them manually after superimposition is not optimal. Thanks in advance for any suggestions and best wishes for 2022

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Introduce a-helices into protein structure ab initio
by Chara Spanou 06 Jan '22

06 Jan '22

Hello chimera-users, I would like to introduce a-helices into my protein structure ab initio. Is it possible to do this with chimera? Another option that I have is to take a-helical pieces of sequence from a different model and introduce these into the desired model. Would that be more feasible? There is a chance I also need to introduce loops and turns ab initio to best localize the introduced a-helices within my protein structure. Can you please indicate how can a chimera user build all this ab initio? Thank you in advance for your time and help, Chara SpanouPhD studentUniversity of Cologne

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report rotate and shift value in MatchMaker
by Yanhe Zhao 06 Jan '22

06 Jan '22

Greeting there, Happy New Year! How can find the rotate and shift value after I done the 'MatchMaker' in Chimera? Thanks and regards, Yanhe

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