- Chimera-users - RBVI Mailing Lists

how to solve the problem of topology
by Kenji MATSUI 31 May '22

31 May '22

Dear Chimera Thank you for your support the other day. I also apologize for contacting you outside of business hours due to the time difference. Excuse me, I have a question about the issue of ligand topology for the docking study. ligand: 25-hydroxy cholesterol The topology did not match when I used this ligand for the docking study. Could you tell me how to solve this problem? The thing I tried 1. I tried to add hydrogen atoms on UCSF Chimera by following the URL below, but it did not work Reference: https://www.swissparam.ch/SwissParam_gromacs_tutorial.html 2. I tried to change the conformation of the C23-24 part, but the situation won't be changed. Reference:< https://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/editing/editing.… > --------------------------------------------------------------------------- Kenji Matsui Graduate School of Tokyo University of Agriculture and Technology M2 2-24-16, Nakamachi, Koganei-shi, Tokyo 184-8588, Japan Mail: s214903z(a)st.go.tuat.ac.jp

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Drawing a set of spheres describing a pocket in a protein
by svle＠tiscali.it 30 May '22

30 May '22

Hi all, I would like to draw a set of colored and transparent spheres that describes a pocket knowing the coordinates of the center and the radius for each of these shapes. For example: radius: 0.7777, y: 18.333, x: -23.99, z: -64.765 and so on. Can you suggest me a way to do this. Thanks. Saverio Voucher MISE per P.IVA e PMI: fino a 2500€ per la Banda Ultralarga. https://casa.tiscali.it/promo/?u=https://promozioni.tiscali.it/voucher_busi…..

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Fwd: [chimerax-users] relative position of a marker
by C.J. 25 May '22

25 May '22

Thank you both Tom and Elaine. I just test the command but it doesn't work. See attached picture. Elaine Meng <meng(a)cgl.ucsf.edu> 于2022年5月25日周三 11:45写道： > Hi Jianhao, > It depends what you mean by relative position. If you mean distance, one > way would be to place a marker at the map center and then measure distance > between it and the marker you already have. > > You can place a marker at map center with "measure center" and the "mark > true" option: > <https://rbvi.ucsf.edu/chimerax/docs/user/commands/measure.html#center> > > ....or at specific coordinates such as 0,0,0 with "marker" and the > "position" keyword to specify a point: > <https://rbvi.ucsf.edu/chimerax/docs/user/commands/marker.html#create> > > Then you can select the two markers (same as atoms) with Ctrl-click, > Shift-Ctrl-click and then use command "distance sel": > <https://rbvi.ucsf.edu/chimerax/docs/user/commands/distance.html> > > Or regardless of whether you wanted to measure any distances, you can save > the marker(s) to file and just look at the file with a text-editor to see > what its coordinates are: > <https://rbvi.ucsf.edu/chimerax/docs/user/markers.html> > > I hope this helps, > Elaine > ----- > Elaine C. Meng, Ph.D. > UCSF Chimera(X) team > Department of Pharmaceutical Chemistry > University of California, San Francisco > > > On May 25, 2022, at 7:54 AM, C.J. via ChimeraX-users < > chimerax-users(a)cgl.ucsf.edu> wrote: > > > > Hi, > > I place a marker in a cryoEM map with "Volume Tracer" tool. How can I > know the relative position of the marker to the origin or center of the > map? Thank you! > > Best, > > Jianhao > >

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HBONDS comparing GROMACS and CHIMERA
by Sourpis, Anastasios 25 May '22

25 May '22

Dear All, I would like to ask about the hydrogen bonds' built-in configuration of CHIMERA. Can I possibly have some insight into how it works? Regarding the distance and angle constraints do you have any graphical representation of the conditions. I would like to attach a figure and ask if this is the correct applying configuration regarding the distance and the angle (hbonds_lst.pdf). Also, I would like to share with you the output when I compare gmx hbond using GROMACS and chimera. ATTENTION: using gmx hbond I have the connected atoms via hydrogen, but the two configurations are essentially different (chimera_(molecules).tga and gromacs_atomonly.tga). Thank you in advance. Kind regards, Tasos Sourpis

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Place Objects output to mrc
by Ricardo Righetto 20 May '22

20 May '22

Hi, Regarding https://www.rbvi.ucsf.edu/pipermail/chimera-users/2022-March/018516.html I stumbled upon this thread somewhat late, so here is my approach to do what Pranav asked, just in case: 1. Use the "Place Objects" plugin to map back your particles into the tomogram, using STL files to represent the average 2. Generate an MRC volume made up entirely of "ones", exactly the same size as your tomogram. For example, for a volume that is 928x928x464 voxels one can do this in EMAN using: $ e2proc3d.py :928:928:464:1 ones_bin4.mrc You could obviously use some other program to do the same thing, or Python, MATLAB, etc. 3. Load this "ones" volume in your Chimera session. Make sure all regions are loaded in step 1, e.g. vol #2 style surface step 1 level 0.5 region all (the volume doesn't have to be visible, though) 4. Mask your "ones" volume using the surface of the mapbacks from "Place Object", e.g.: mask #1 #2 fullmap true 5. Save the new, masked volume as an MRC file The result is essentially a binary volume (well, not exactly because of the masking interpolation) where voxels of your mapped-back particles are 1 and the rest is 0. This is quite useful to compose segmentations and mapbacks on tomograms in Chimera or ChimeraX having full control like we do with any MRC volume (unlike e.g. STL or COLLADA objects). Note you may get some artifacts on the edges, so you might have to play a bit with the thresholds both when creating the STL of your subtomogram average and when displaying your new volume "sculpted" by the mapbacks, to minimize those. The results however have been good enough in my experience, working with low-resolution averages :-) Hope this helps! Best wishes, -- Ricardo Diogo Righetto

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Allocating GPUs
by Giono Matteo (PSI) 19 May '22

19 May '22

Dear all, Does anyone know if it’s possible to make Chimera use GPUs instead of CPUs? I have a 2021 Macbook Pro with 12-core GPUs and knowing that all the work is done by the CPU make all these GPUs kind of useless. Best, MG

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USCF CTRL + Left Click
by Luke Kurfman-Student 19 May '22

19 May '22

Hello Sr./Ms., Most everyone in my laboratory has access to UCSF Chimera and can use it with no issues. However, one new person has had trouble selecting atoms. Specifically, neither CTRL + Left Click nor CTRL + SHIFT + Left Click appear to work on selecting atoms in a molecular geometry, even though their computer can run the program. They can translate, rotate, and zoom in-and-out of the geometry, and they can use actions such as "Select All" . However, they cannot deselect individual atoms once the entire geometry is selected, and they can only CTRL + Left Click outside the geometry to deselect the entire geometry. Additionally, drag-clicking does not appear to work. CTRL + Click is a fundamental feature that our group uses, especially since we use Chimera for journal figures. Are there any suggestions on how to troubleshoot the issue with selecting atoms? For reference, their computer runs Windows 10 and operates on a x64 bit system. Any help is appreciated, Luke

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Set scale factors from displayed contours?
by Oliver Clarke 17 May '22

17 May '22

Hi, When combining maps using vop maximum (or volume maximum in chimerax), we often want to adjust the scale factors of the maps such that the overlapping bits of two aligned maps are visually on the same scale. It is possible to calculate the appropriate scale factors from the displayed thresholds, but this becomes a little time consuming when combining many maps. Would it be possible to add a flag, something like "get scalefactor from display thresholds" that would take care of this automatically? Cheers Oli

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Assigning nucleotide representation to non-canonical nucleotides
by Jérôme Rihon 16 May '22

16 May '22

Dear I was wondering if there is a way to represent non-canonical (otherwise known as xenobiotic) nucleic acids through UCSF Chimera (specifically, not ChimeraX .. haven't made the jump yet). I've looked through your documentation on the `nucleotides` section but was not able to find something along those lines. My PI told me it was possible, but I can't seem to find it. My apologies if I should be looking for this function elsewhere, but I thought it'd be easier to just ask. Many thanks in advance! Kind regards, Met vriendelijke groeten, Cordialement, ______________________ Rihon Jérôme jerome.rihon(a)kuleuven.be | +32 16 32 53 57 PhD researcher @Rega Institute for Medical Research | Laboratory of Medicinal Chemistry | Computational Research Herestraat 49 - box 1041, 3000 Leuven

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Making a movie from map series while keeping map's colors
by Michal Arie Shmuelov 16 May '22

16 May '22

Hi everyone, I have 20 maps (from 3D variability analysis) that I open as series in chimeraX. I'm coloring the map series using the command "color zone #X near #X distance X" (coloring the map according to pdb model). Next I'm trying to make a movie of this map series while retaining the map colors. For some reason when the morph/ vseries starts to run the colors disappear. Can someone help me to solve this problem? What are the commands that I should write? Thanks, Michal

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