April 2016 - Chimera-users - RBVI Mailing Lists

Hidden water molecules
by Michael Sharkey 11 Apr '19

11 Apr '19

Hi I'm trying to visualise water molecules associated with the crystal structure of an enzyme (specifically PDB ID: 1C1D). They're listed when I open the pdb as a text file using WordPad, but I can't for the life of me get them to appear on the screen when I try to visualise the structure in Chimera (v. 1.10.2). What am I missing? Thanks in advance Mike --

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Constrainted fitting
by Christoph Wigge 22 Mar '19

22 Mar '19

Dear all, I would like to fit two protein monomers that form a dimer into an em density map. I know from previous mutagenesis studies that the binding takes place with two tryptophan residues and the counterpart binding pocket. How can I set this interaction as fixed so that chimera fits the rest of the molecule according to the density map without continuously changing this part of the essential protein protein interaction? I would like to fit that interaction manually and then exclude it from the automatic procedure. Thank you very much in advance. Bests Christoph Wigge

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volume planes tool
by Jeff Triffo 22 Jun '16

22 Jun '16

hi folks, anyone know if the volume plane tool will support arbitrary orientation of the plane any time soon? -Jeff

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Re: [Chimera-users] [chimera-dev] suggestions for better STL export - remove internal, reduce atom vertices
by Tom Goddard 09 May '16

09 May '16

Hi Jakob, We discussed the excessive STL vertices in atoms and bonds last week and I put a fix into the daily build and release candidate. http://plato.cgl.ucsf.edu/pipermail/chimera-users/2016-April/012134.html Apparently you are not using those versions since your images show the high vertex density. I’ve attached an image using the current Chimera release candidate that shows reasonable vertex density. Unfortunately eliminating internal structures and stitching together meshes for atoms, bonds and ribbons at the seams is very difficult. Yes $10000 CAD software packages can do it but we don’t have the resources to solve that problem. Since every 3d printer has to deal with this problem I expect the printer software to be able to handle it, but perhaps it is too hard a problem for the 3d printer companies as well. Perhaps there is free software that can eliminate internal structures and stitch mesh intersecting edges together, I have not researched it — I’d start looking at MeshLab. Tom > On Apr 15, 2016, at 4:33 AM, Jakob Suckale wrote: > > Dear Chimera developers, > > Chimera has the great feature of STL export, very useful for 3D printing models for research and teaching. May I make two suggestion to improve this feature even further. > > > 1 - Remove invisible internal and therefore unnecessary structures. > > Chimera generates a lot of internal structures that complicate printing and are pointless for STLs. This includes inside surfaces at the end of ribbon cartoons (red below). > <Screen Shot 2016-04-15 at 13.24.44.png> > as well as copious amounts of invisible internal surfaces for wire and ball and stick models. > <Screen Shot 2016-04-15 at 13.27.36.png> > If these were automatically removed, STLs would not only be much smaller but also much easier to print without remashing. > > > 2 - Reduce the number of vertices for atom models. > > Ribbon conversion to vertices is already good, but as can bee seen above atom models are converted using far too many vertices inflating the resulting STL files. I'm aware that this has been discussed and listed previously as a bug but the problem remains and makes for difficult to use STLs and bad 3D prints. > > Best regards, > > > Jakob Suckale, PhD > Lecturer in Biochemistry > University of Tübingen > +49-7071-29-73363 > _______________________________________________ > Chimera-dev mailing list > Chimera-dev(a)cgl.ucsf.edu > http://plato.cgl.ucsf.edu/mailman/listinfo/chimera-dev

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Solicitud Información
by luz Martinez 02 May '16

02 May '16

Cordial Saludo Soy estudiante de licenciatura en Química de la UNIVERSIDAD PEDAGOGICA NACIONAL. Colombia, Cordialmente solicito información acerca del modelo matemático general que el programa UCSF Chimera utiliza, lo anterior con el fin llevar a cabo una investigación en el espacio académico de Química Computacional que curso. Agradezco la atención y pronta respuesta Luz Angela Martinez M. Estudiante Decimo semestre

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Manually adjusting alignment
by Visvaldas K. 30 Apr '16

30 Apr '16

Dear All, I wasn't able to adjust alignment in the Alignment window, and search did not find an answer (because I get great number of false negatives)...I tried shift-arrow, ctrl-shif-arrow and many times but only once the region moved "by accident", and I wasn't able to repeat this feat. To simplify the task, let's say I have in the alignment window: seqA NQDF.RFRDseqB MKTFIEHKD I want to move "RF" by one residue to the left so that the top part becomes NQDFRF.RD What would be the sequence of keys, clicks/drags and so on to do that (also, how is the active region which is ready to move signified: green, green in a dashed frame, or perhaps white dashed frame)? Sincerely yours, Vis Kairys

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need help joining existing pdb files with new sequence
by John Hess 28 Apr '16

28 Apr '16

HI folks, I have asked Elaine a couple questions about this project of mine. She’s been very helpful, but I’m such a beginner, I feel guilty wasting her time and the rest of the folks reading the entire chimera list as I ask how to connect this and move that. I would like to take at least 2 existing pdb files and link them to some additional peptides sequence that would be between them. The resulting pdb would describe a structure that looks like this: > protein 1 -> peptide linker -> protein 2 I’m dealing mainly with alpha helices (in coiled-coils), and I know how I want them positioned. I joined a helical peptide sequence (made using Build Structure) to one pdb file but the orientation was way off and I’m wondering how to “grab” the entire helical peptide region and move it where I want it (sorry, in the past, I have tried to modify structures with Foldit and have had a collaborator who used Rosetta to try and model my data.). Is anyone else on this list from UC Davis and willing to get together for some tutoring? Does anyone not at Davis have time to answer my questions and help? If we work well by email and I make progress, I think that this could be a $ for time or co-authorship situation. thanks, John Hess jfhess(a)ucdavis.edu

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Labeling and coloring chains
by Elaine Meng 28 Apr '16

28 Apr '16

> On Apr 28, 2016, at 8:15 AM, Deniz Simsek Buck <simsekd(a)stanford.edu> wrote: > > Hi Elaine, > Thank you for your reply. > > I already changed the chain IDs to different names. I am working with ribosome structure: 44 chains are large subunit and then I want to color them the same color. > If I already changed chain A to L23, lets say, how do I choose them? > > Also, is there a way to choose different colors than the available ones and also how do I make the label the same color as the chain? > > Thank you very much, > Deniz > Hi Deniz, I do not know how you changed the chain names, so it is hard to say. In PDB format there is only one column allotted to chain ID in the ATOM lines, <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/tutorials/pdbintro.html#co…> ...so it can only be one letter or number, as far as I know. So it would depend on what Chimera thinks are the chain IDs…. for example, it may have only read the single character in column 22 as the chain ID. You could probably tell by putting the mouse over some atom in the chain and see what information is in the pop-up balloon. But maybe you used some other format that allows more characters of chain ID. Nevertheless, it might not be possible to use the range syntax I showed in my previous message (first example included below). You could try it, but if ranges didn’t work, you’d have to specify all the IDs (again, all of what Chimera thinks are the IDs) in one long command, or in multiple separate coloring commands. > color red,r :.A-D > (meaning: color red ribbons-only in chains A-D in all models) > > color green,a #0:.B,.D > (meaning: color green atoms-only in chains B and D of model #0) Instead of changing chain IDs I would recommend using “alias” to give new names to the set of atoms and then use these new names in the coloring commands, e.g. alias L23 :.X (meaning assign the name L23 to chain X) color hot pink,r L23 … of course you could assign the name to a collection of multiple chains if you wanted, e.g. alias L23 :.X,.Y,.H You could also use alias with your existing changed chain IDs providing you can figure out what Chimera thinks they are. As for colors, you can specify an infinite number of colors as RGBs or hexadecimal or first define new color names and use those names, if the built-in set of named colors doesn’t have what you need. Color specification is described in the same “color” manpage I mentioned before. <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/color.html> Also described in that page are how to specify coloring labels, e.g. color orange,r,l (meaning coloring ribbons and labels only) Again I’ve CC’d the recommended address for chimera questions, chimera-users(a)cgl.ucsf.edu I hope this helps, Elaine ---------- Elaine C. Meng, Ph.D. UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco

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Three-dimensional structural model of the VP7 trimer
by Dr Omer Naseer 28 Apr '16

28 Apr '16

Hi I am s student of PhD and working on the Rota virus A, I want to created "three-dimensional structural model of the VP7 trimer". by using "UCSF Chimera", can you please tell me How to do this? because I tried a lot but unable to produce a structure like yours. Regards Dr, Omer Naseer Ph.D Scholar University of Veterinary & Animal Sciences, Lahore, Pakistan. +92 321 640 89 56

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The question about fitting
by Zhongjun Hu 28 Apr '16

28 Apr '16

Hi, everyone: Once I fit one map to the reference map, there will be some fitting result. I want to use this fitting result to align the map to the reference map using another software, for example, EMAN. How do I this? It seems that I am not clear about the fitting result, could anyone give some idea? or, is there other protocol/software to do this? Thank you! Best, Zhongjun

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