June 2010 - Chimera-users - RBVI Mailing Lists

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] Display a spider volume data in a specific orientation
by Elaine Meng 08 May '14

08 May '14

Hi Zongli, This is not my area of expertise (our expert is currently out of town) -- at first I thought you could use "Transform Molecule Coordinates" (under Tools... Movement), but now I see that it works only on atomic structures rather than maps: <http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/transform/transfor… > It only works on molecular structures because it actually changes the atomic coordinates, without changing the model transformation. I've figured out one workaround, but it is both crazy and slightly tedious: (1) open your map (say as model 0). (2) open any atomic-resolution structure, it doesn't matter what, and open it twice -- now you have three models. Don't move them separately from the map (yet). Let's say the atomic structures are models 1 and 2. (3) use "Transform Molecule Coordinates" with desired Euler angles and shift on one copy of the atomic structure (say model 1). (4) use the match command to superimpose the other copy of the atomic structure on the one that was transformed: match #2 #1 (the command can use the whole models since they should have exactly the same atoms) (5) use the matrixcopy command to apply the transformation matrix of the second copy of the atomic structure to the map: matrixcopy 2 0 You might think "why do I need two copies of the atomic structure? can't I just transform one copy and then use matrixcopy?" ... in fact that's what I tried first, but after it didn't work, I realized it was because the Transform tool works by changing the coordinate values and not the stored matrix of the model. It is necessary to match the second copy to generate a corresponding matrix, and then matrixcopy can be used. I'm CC-ing the chimera-users(a)cgl.ucsf.edu list in case other Chimera users have suggestions. Our expert Tom G should be back next week and he might also have ideas. In general, it's better to send Chimera questions to that mailing list instead of just me, because I could be away from work or (like now) lacking a good answer! 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 On Apr 7, 2010, at 11:51 AM, Li, Zongli wrote: > Hi Elaine, > I have a spider volume data (or mrc density map) from which I got a > serious 2D projections. I have the Euler angles for each projection. > Is there a way in Chimera that I can use those Euler angles to > display the 3D spider volume data (or mrc density map) in a specific > orientation that corresponding to that 2D projection? > Thank you very much in advance. > Best, > Zongli > > **************************************** > Zongli Li, Ph.D. > > Howard Hughes Medical Institute > Department of Cell Biology > Harvard Medical School > C Building, Room 420B > 240 Longwood Avenue > Boston, MA 02115 > > Tel: 617-432-4095 (Office) > 617-432-4708 (EM Suite) > 617-432-4091 (Computer room) > Fax: 617-432-1144 > Email: zongli_li(a)hms.harvard.edu > *************************************** >

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color surface based on NMR Order parameters
by lalit.deshmukh＠huskymail.uconn.edu 08 Sep '11

08 Sep '11

Hello, I like the 'surface color ' feature in Chimera. I think, right now, the surface can be colored by radius, height, volume data and so on.. Is it also possible to color the surface based upon the NMR order parameters or intensity ratios (it will be an Excel file containing just two columns: residue numbers and the respective parameter values)? Or this can be done in some other way? Thanks in advance, Regards, Lalit Deshmukh, University of Connecticut Storrs, CT 06269

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square of density volume
by 仁田亮 13 May '11

13 May '11

Hi chimera users, I want to calculate the square value for the volume of the electron density because I want to calculate the variance map. Do anyone know whether we can calculate the square value of the volume by chimera? And if we can, could you teach me how to calculate? Thanks for your time and help, Ryo

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bond rotation
by Elaine Meng 06 Jan '11

06 Jan '11

On Jun 25, 2010, at 10:20 AM, Watson, Lisa wrote: > Hi Elaine, > I have changed several nucleotide bases in the DNA structure I am working with so that I can model in cytosine methylation. Is there a way that I can rotate the changed bases so that they are aligned to base-pair properly? > Thanks for your help! > -Lisa Hi Lisa, Sure, you can interactively rotate bonds. If you Ctrl-doubleclick a bond it should show a little menu where one of the choices is to rotate that bond. After you activate the rotation, the "adjust torsions" dialog will appear, which includes various ways to rotate the bond. You can have several rotatable bonds at the same time. Here is more about Adjust Torsions: <http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/structuremeas/stru…> Also, the tutorial "Structure Comparison and Analysis" includes measuring distances, finding H-bonds and clashes, and rotating bonds: <http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/tutorials/squalene.html> 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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Silhouette edges around dashed wire-style bonds
by Dipl.-Ing. Thomas Mitterfellner 05 Jan '11

05 Jan '11

Hello! In some of my structures, I need dashed bonds to indicate hydrogen bonding or metal complexation. As I understand it, in order for bonds to be displayed as dashed, they need to be wire-style. I wondered if silhouette edges could also be extended to these wire-style bonds? Alternatively, could stick-style bonds possibly be displayed in a dashed fashion? Maybe as a series of cylinders, each separated by a certain distance, or eg. as a series of equally spaced small spheres. Thank you, Thomas

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renumber model IDs
by Dougherty, Matthew T 24 Jun '10

24 Jun '10

There are a number of times I would like to change the model ID numbers. Sometimes it is because a researcher gives me a session file that has sequences like monomer-b, monomer-d, monomer-a, monomer-c; or sometimes when I got an easy sequence to memorize (monomer-a, monomer-b, monomer-c, monomer-d), I do a colorzone split map that causes sequence names to comeback in a different order (monomer-b, monomer-d, monomer-a, monomer-c). Is there a way using commands to maintain better ID order?

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Re: [Chimera-users] structure based sequence alignment
by Eric Pettersen 24 Jun '10

24 Jun '10

Hi Sonya, On Jun 24, 2010, at 7:39 AM, Sona Vasudevan wrote: > Hello Eric, > > Thanks for all the great features you have added in the last couple > of years since I was last in touch with you. This is a fantastic tool! Thanks! Glad you like it. > I need some help with the alignment editor. > > I am trying to import an alignment in fasta format (fasta aligned) > (see attached). The alignment as you can see has three structures. I > use Load structures from the sequence > window and it brings in all the chains corresponding to teh > structures. It does, but there's a subtlety here that I should point out. The first two sequences in the alignment are for 1XVA, chain A and chain B. Chimera opens two copies of 1XVA and associates one copy with each sequence, but it associates chain A in both, since the sequences of the two chains are identical. It doesn't really look at the sequence name to try to figure out which chain to associate, just how well the sequences match and in this case they both match perfectly. By hovering the mouse over the sequence name you can see which structure/ chain it is associated with. To change the association of the second sequence to use chain B, you need to go to the alignment's Structure menu and choose "Associations...". Thus will bring up a panel showing the association of each structure to a sequence. Change the association of "1xva (#1)" from "chain A" to "chain B" and then click OK. > I then use Matchmaker to align them. I have a few questions: > > 1. Does the match maker use the info from the imported alignment > since the structures are already aligned? In other words is the > structural alignment I am seeing the saem as that was imported. No. MatchMaker is its own tool and doesn't use any open alignments. After all, you could have several alignments involving those structures open. If you want to superimpose the structures based on your alignment, use the alignment's own "Structure->Match" menu item. That brings up a dialog offering a variety of options as to how to carry out the match. I like using the "Iterate" option, but it's totally up to you. > 2. Is there a way to just output the superposed co-ordinates without > the chains that are not being used? There are probably several ways. One that comes to mind is to click on one of the alignment's "Consensus" letters to select all the residues in that column. Then click into the graphics window and hit the up-arrow key to expand the selection to the entire chain. Then either choose Select->Invert or hit right-arrow to invert the selection -- now the unused chains are selected. Actions->Atoms/Bonds- >delete will delete them. You can then write out what's left. Keep in mind that if you want to get model 2's coordinates as superimposed with model 0's original coordinates (for instance) then make sure to use the "relative 0" option in the "write" command or check the "Save relative to" option in the Write PDB dialog and choose model 0. Or you could just write out all models current coordinates. They will all differ from their originals, but they will be superimposed. > 3. Looks like I can add sequences to the alignement. Can I add a > fasta file with many sequences? No. It is on my to-do list but I haven't gotten to it yet. I'll open a feature-request ticket in our Trac database with you on the recipient list so you'll know when it gets implemented. Sorry! > Thanks so much! I have alignment files for 100 families which are > high-qualityas they were manually aligned with Cn3d and I would like > to import them into chimera for further analysis. > > Thanks so much for your time! You're welcome! --Eric Eric Pettersen UCSF Computer Graphics Lab http://www.cgl.ucsf.edu

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Paint a pseudobond....
by Yasser Almeida Hernández 24 Jun '10

24 Jun '10

Hi... I want to connect two atoms that belongs to different models with a pseudobond. It's that possible with Chimera? If it does, how would be the Python API code? Thanks ;) -- Yasser Almeida Hernández, BSc Center of Molecular Inmunology (CIM) Nanobiology Group P.O.Box 16040, Havana, Cuba Phone: (537) 214-3178 almeida(a)cim.sld.cu ---------------------------------------------------------------- Correo FENHI

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Question about attribute assignment file
by Peng Ni 24 Jun '10

24 Jun '10

Hi, I am trying to use the define attribute function. However, the attribute assignment sheet I generated cannot be read. It reports: "Line 1 of file is either not 'name: value' or is missing initial tab". I cannot spot anything wrong in my txt file, which is also attached in the e-mail. I'd greatly appreciate it if you could help me fix this problem. Regards Peng

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