June 2025 - Chimera-users - RBVI Mailing Lists

Request for Mathematical Details or Source Code for Helix Axis and Interhelical Distace/Angle Calculations in Chimera
by pupadhyay21 23 Jun '25

23 Jun '25

Respected Sir/Madam, My name is Prashant Upadhyay, and I am currently pursuing a Ph.D. in Bioinformatics and Molecular Dynamics Simulation at the Indian Institute of Technology Kanpur (IIT Kanpur), India. As part of my research, I am analyzing the structural dynamics of helical membrane proteins using molecular dynamics simulations. I have been using UCSF Chimera extensively for structural analysis. Specifically, I have been utilizing the Structure Analysis → Axes/Planes/Centroids tool to calculate the helix axes of selected helices in my protein of interest. When I select two helices, the Reply Log provides the interhelical distance and angle between the computed axes. This functionality has been incredibly useful for analyzing static structures. To extend this to a dynamic context, I am interested in applying the same axis and angle calculation to each frame of an MD trajectory. For this, I would greatly appreciate it if you could share the mathematical methodology or the relevant portion of the source code that Chimera uses to compute: 1)The helix axis from selected residues 2)The angle and the shortest distance between two helix axes My aim is to replicate this analysis programmatically over the entire simulation trajectory. Any guidance, reference, or code snippet you could provide would be immensely helpful. Thank you, Prashant Upadhyay Ph.D. Student Department of Biological Sciences and Bioengineering Indian Institute of Technology Kanpur (IIT Kanpur)

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Request for Mathematical Details or Source Code for Helix Axis and Interhelical Distace/Angle Calculations in Chimera
by pupadhyay21 22 Jun '25

22 Jun '25

Respected Sir/Madam, My name is Prashant Upadhyay, and I am currently pursuing a Ph.D. in Bioinformatics and Molecular Dynamics Simulation at the Indian Institute of Technology Kanpur (IIT Kanpur), India. As part of my research, I am analyzing the structural dynamics of helical membrane proteins using molecular dynamics simulations. I have been using UCSF Chimera extensively for structural analysis. Specifically, I have been utilizing the Structure Analysis → Axes/Planes/Centroids tool to calculate the helix axes of selected helices in my protein of interest. When I select two helices, the Reply Log provides the interhelical distance and angle between the computed axes. This functionality has been incredibly useful for analyzing static structures. To extend this to a dynamic context, I am interested in applying the same axis and angle calculation to each frame of an MD trajectory. For this, I would greatly appreciate it if you could share the mathematical methodology or the relevant portion of the source code that Chimera uses to compute: 1)The helix axis from selected residues 2)The angle and the shortest distance between two helix axes My aim is to replicate this analysis programmatically over the entire simulation trajectory. Any guidance, reference, or code snippet you could provide would be immensely helpful. Thank you, Prashant Upadhyay Ph.D. Student Department of Biological Sciences and Bioengineering Indian Institute of Technology Kanpur (IIT Kanpur)

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ChimeraX menu
by Elaine Meng 13 Jun '25

13 Jun '25

Hi Mariela, Your picture #1 is Chimera. Picture #2 is ChimeraX. These are two different programs. To get ChimeraX, you have to go to the ChimeraX website and download it: <https://www.rbvi.ucsf.edu/chimerax/download.html> If you meant that you do already have ChimeraX, but the Toolbar with icons is not shown, use ChimeraX menu: Tools... General... Toolbar to show it. See ChimeraX window and Toolbar help: <https://rbvi.ucsf.edu/chimerax/docs/user/window.html> <https://rbvi.ucsf.edu/chimerax/docs/user/tools/toolbar.html> If you have ChimeraX questions, please use address chimerax-users(a)cgl.ucsf.edu <mailto:chimerax-users@cgl.ucsf.edu> CC'd here. The other address chimera-users[...] is for Chimera. I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Resource for Biocomputing, Visualization, and Informatics Department of Pharmaceutical Chemistry University of California, San Francisco > On Jun 13, 2025, at 5:34 AM, Mariela Urrutia via ChimeraX-users <chimerax-users(a)cgl.ucsf.edu> wrote: > > Hi Eric > I send you the menu I have (adjunto 1) and the menu I would like to have in my CPU (adjunto 2). > Could you tell me please how can I add it? > Thanks you. > Mariela > > De: Eric Pettersen <pett(a)cgl.ucsf.edu> > Enviado: Jueves, 12 de Junio de 2025 14:14 > Para: Mariela Urrutia <murrutia(a)cedie.org.ar> > CC: chimera-users(a)cgl.ucsf.edu <chimera-users(a)cgl.ucsf.edu>; Alexis Rohou via ChimeraX-users <chimerax-users(a)cgl.ucsf.edu> > Asunto: Re: [Chimera-users] query > Hi Mariela, > I don’t really know what a “superior menu” is. Maybe you could clarify? If you mean a popup menu, you get that by clicking the right button on your mouse (or the equivalent on a trackpad). > Since this is a ChimeraX question, I have cc’ed the chimerax-users list and directed replies there. Chimera and ChimeraX are separate programs and have separate mailing lists. > > --Eric > > Eric Pettersen > UCSF Computer Graphics Lab > > > On Jun 12, 2025, at 9:23 AM, Mariela Urrutia via Chimera-users <chimera-users(a)cgl.ucsf.edu> wrote: > > Hello, > Could you give me direction to add the superior menu in ChimeraX 1.9 (2025-3-6)? > Thanks you in advance! > Mariela > Dra. Mariela Urrutia > Investigadora > Centro de Investigaciones Endocrinológicas “Dr. César Bergadá” (CEDIE) > CONICET – FEI – División de Endocrinología, Hospital de Niños Ricardo Gutiérrez > Gallo 1330 – C1425EFD Buenos Aires – Argentina > Tel. (+54-11) 4963-5931 int 290 > murrutia(a)cedie.org.ar 🌎 www.cedie.org.ar 👥 Facebook Instagram > _______________________________________________ > 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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Composite map: select only voxels within a range of resolution?
by Samuel Leite Guimaraes 12 Jun '25

12 Jun '25

Hi! I recently processed a cryo-EM map using icosahedral symmetry, achieving a decent global resolution. Then, using localized reconstruction, I improved the resolution of the asymmetric unit (ASU). However, some regions of the ASU still showed poor connectivity. To address this, I generated several additional localized reconstructions, focusing on specific regions of the ASU (taking advantage of the 2-fold, 3-fold, and 5-fold symmetry axes) to improve their local resolution. Now, I want to create a composite map in Chimera by combining the best-resolved regions from each localized reconstruction. However, instead of simply using the voxel-wise maximum density values (as done with vop max), I would like to select voxels based on the best local resolution — i.e., for each voxel position, use the value from the map where that voxel has the highest resolution (lowest local resolution value), as indicated by the associated local resolution maps. Is this type of composite map creation — resolution-guided voxel selection — possible in Chimera (or ChimeraX)? Thanks in advance! Samuel L. Guimarães Aviso Legal: Esta mensagem e seus anexos podem conter informações confidenciais e/ou de uso restrito. Observe atentamente seu conteúdo e considere eventual consulta ao remetente antes de copiá-la, divulgá-la ou distribuí-la. Se você recebeu esta mensagem por engano, por favor avise o remetente e apague-a imediatamente. Disclaimer: This email and its attachments may contain confidential and/or privileged information. Observe its content carefully and consider possible querying to the sender before copying, disclosing or distributing it. If you have received this email by mistake, please notify the sender and delete it immediately.

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query
by Mariela Urrutia 12 Jun '25

12 Jun '25

Hello, Could you give me direction to add the superior menu in ChimeraX 1.9 (2025-3-6)? Thanks you in advance! Mariela Dra. Mariela Urrutia Investigadora Centro de Investigaciones Endocrinológicas “Dr. César Bergadá” (CEDIE) CONICET – FEI – División de Endocrinología, Hospital de Niños Ricardo Gutiérrez Gallo 1330 – C1425EFD Buenos Aires – Argentina Tel. (+54-11) 4963-5931 int 290 murrutia(a)cedie.org.ar<mailto:murrutia@cedie.org.ar> 🌎 www.cedie.org.ar<https://cedie.conicet.gov.ar/> 👥 Facebook<https://www.facebook.com/CEDIE-Centro-de-Investigaciones-Endocrinol%C3%B3gi…> Instagram<https://www.instagram.com/cedie.conicet/>

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Chimera on RHEL10 or Fedora 42 with Wayland
by Ben Webb 10 Jun '25

10 Jun '25

RedHat Enterprise Linux 10 has dropped Xorg in favor of Wayland, and Fedora 43 will likely do the same. Fedora 42 already uses Wayland by default. Is Chimera expected to work with Wayland? ChimeraX works fine in our environment with Wayland, but I have folks that still want to use Chimera. And they're getting a Togl failure at startup: "Display misconfiguration. Please increase the color quality (24 bit color or greater), update your display (graphics) driver, and/or upgrade your graphics card. Also see chimera installation instructions." I would love to tell them that "the Chimera folks say it doesn't work with Wayland so you need to switch to ChimeraX" (we can eke out another six months or so with Fedora 42 using Xorg) but if you think it *should* work, any clues as to where to look to tweak our configuration? Other than using the NVIDIA drivers (570.133.07), we are using a stock Fedora and Wayland install.

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