August 2006 - Chimera-users - RBVI Mailing Lists

Re: [Chimera-users] Electrostatic Potentials
by Thomas Goddard 08 Aug '06

08 Aug '06

Hi Nihshanka, Oops! My previous descriptions of how to determine electrostatic potential values at specific surface points assumed you were using the Surface Color tool to display the potential (menu entry Tools / Structure&Binding Analysis / Electrostatic Surface Coloring, or menu entry Tools / Volume Data / Surface Color). But you are using DelphiController and it has its own code for displaying potential values for which my previously described techniques will not work. To print the potential values at every surface point when the potential display was done with Delphi Controller you could put a print statement in chimera/share/DelphiViewer/MSMSTexturer.py at line 155, after the following lines of code else: # Point is outside of phi map. phivalue = 0 add the line print v_rs, phivalue Make sure the "print" line is indented the same as the "else:". This is going to print many thousands of lines in the Reply Log so be prepared to wait a bit. You could also use my previously described methods for showing potential values by using the Electrostatic Surface Coloring tool. Show a surface for your PDB model using Actions / Suface / show. Then in the Electrostatic Surface Coloring dialog press the "Open map data..." button and select the *.phi file generated by DelPhi (the one computed when running Delphi Controller). Then press the Color button on the surface color dialog. My previous code modification or the marker probe method could them be used. Tom

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Electrostatic Potentials
by Nihshanka Debroy 07 Aug '06

07 Aug '06

Hi everyone, I have a couple of questions about the electrostatic potentials generated in Chimera using the Delphi Controller. If I have a protein with 5 chains A,B,C,D,E, and I choose to show the surfaces of all chains except C (but keep the wireframe of chain C's atoms) and then run Delphi using the DelphiController, does that mean that the potential surface generated is in the absence of chain C (which is what I want)? I'm trying to generate the potential surface without taking into account chain C, but would like to see C's wire frame for analysis purposes. Also, is there a way to get the actual potential values at each surface coordinate? Thanks a lot for the help. Sincerely, Nihshanka

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coloring carbon and deleting hydrogens
by Narender Singh Maan 04 Aug '06

04 Aug '06

Dear all, I am trying to show two residues of a protein structure with 50% surface transparency along with a stick model (rest of the protein is 0% surface transparent). Now in this i am having trouble in showing those stick residues in a different color (for e.g. the default for C atom is gray, which i want to show in green). Is there anyway in which i can do it?. also for those two residues i want to delete the hydrogens (only in stick, and not in surface representation)? any suggestions would be of great help. Thank you

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Coloring binding modes according to an energy term with ViewDock
by Vincent Zoete 04 Aug '06

04 Aug '06

Hi, Does it exist a way to color the different ligand positions obtained during a docking run, and displayed by the Viewdock module of chimera, as a function of a given energy term present in the columns of the viewdock table? If not, I think this could be an useful option to add to chimera. Also, it could be interesting to have the possibility to display the color scale as a function of the energy term together with the structures. If it cannot be done in the chimera display, it could be in the generated figures. Otherwise, congratulation for the great job the UCSF computer graphics lab is making with Chimera! Thank you for your time. Sincerely, Vincent

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Re: [Chimera-users] X3D to VRML conversion
by Thomas Goddard 01 Aug '06

01 Aug '06

> Date: Tue, 01 Aug 2006 12:27:52 -0700 > From: Ben Morris > > Hey Tom, > > Were you using the chimera VRML viewer when you tested the new x3d2vrml > output? I had the same exact problem in my testing of the code before > submitting it, and Conrad told me that the Chimera vrml viewer is less > than perfect when it comes to complex geometry (surfaces and ribbons). I > don't know if you were using Chimera, or even if it is the only problem, > but when I tested the code using a third party viewer, ribbons and > surfaces worked fine! > > ~Ben Hi Ben, Yeah, I tested Chimera VRML output by reading it back into Chimera. I agree that the fact that ribbons did not display properly could very well be a problem with the Chimera VRML renderer rather than the output. I just displayed a Chimera round ribbon (1a0m) using FreeWRL 1.15 on Linux and it displayed correctly. It gave about 30 warnings like the following which may or may not be important: WARNING -- node Normal may not be ok as a field of type normal (...called from VRML::Field::SFNode, 1363) It sounds like you are the one who have worked on the Chimera VRML output rather than Greg. Thanks for working on this. I think it will be useful to many people. Tom

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X3D to VRML conversion
by Nihshanka Debroy 01 Aug '06

01 Aug '06

Hi Dr. Meng, Thank you for your informative reply. That was very helpful. I was wondering if I could ask another quick question. I don't think that in Chimera, using the VRML format one can save non-surface information, like the backbone structure of a peptide (but one can display it). So I saved the information in X3D. And now, I'm trying to convert back to VRML format to be able to display it. I got completely lost when looking for some software to do this conversion. I tried using something called X3D to VRML97, but got a "segmentation fault" when I tried to open up the created VRML file. Has anyone faced this sort of an issue ? Thanks a lot, Nihshanka

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