- Chimera-users - RBVI Mailing Lists

help with error message
by Susan Tsutakawa 28 Nov '11

28 Nov '11

I am opening up a pdb that has been generated after MD simulations. Waters have been removed. I am getting an unusual error. I have two pdb files that were generated similarly, but only one gives me the error. Traceback (most recent call last): File "/Applications/Chimera.app/Contents/Resources/share/chimera/tkgui.py", line 343, in openPath mols = chimera.openModels.open(path, type=ftype) File "/Applications/Chimera.app/Contents/Resources/share/chimera/__init__.py", line 1541, in open models = func(filename, *args, **kw) File "/Applications/Chimera.app/Contents/Resources/share/chimera/__init__.py", line 770, in _openPDBModel errOut=errLog) error: radius must be positive Error reading bfactor-911_changed.pdb: error: radius must be positive File "/Applications/Chimera.app/Contents/Resources/share/chimera/__init__.py", line 770, in _openPDBModel errOut=errLog) If someone can help, I would appreciate it.

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Error in viewing trajectories
by George Tzotzos 28 Nov '11

28 Nov '11

Yesterday I posted a message regarding Chimera issuing error messages on trying to open trajectory files. The error was "TypeError: Attempt to form duplicate covalent bond." I believe that the problem arises from the fact that in preparing the topology files with ANTECHAMBER (tleap) in AMBER, I generated disulfide bonds. My guess is that the problem lies there. Has anyone observed similar behaviour? Best regards George

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EM density fitting
by dhacademic 28 Nov '11

28 Nov '11

Hi, I have an EM density map of a protein, as well as several PDB structures, and want to find the most possible structure with the lowest fitting score. Can anyone tell me know how to calculate the fitting score between the EM-density map and a PDB structure in chimera? Many thanks! Best, Hao

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TypeError: Attempt to form duplicate covalent bond.
by George Tzotzos 27 Nov '11

27 Nov '11

Hi everybody, I'm trying to load a trajectory and I get the error message shown above. I'm attaching the error log in case it's of any help. The problem is that I'm able to load the trajectory in VMD without problems (prefer to work on Chimera, though). Any help on how to troubleshoot this would be most welcome. Have a good weekend George

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3D custom residue labels
by matheus froeyen 22 Nov '11

22 Nov '11

Hi I tried the command mode options to generate a custom hard coded 3D residue label: labelopt resinfo "ARG 167" rlabel offset 0.,0.,20. :151 however get an error in the labelopt command: "resinfo" keyword does not exist (although it is described in the chimera man pages) Then I tried to bypass this by using the atom labeling labelopt info "ARG 167" label offset 0.,0.,20. :151@CA but again no luck, then is displayed the label "none" in the 3D window the default residue labeling works however. How can I use custom labels without using the menus? I use chimera 1.5.3 build 33475 on mac osx. best regards mathy

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2dlabels with solid background
by Tom Goddard 21 Nov '11

21 Nov '11

Hi Gabe, Unfortunately there is no color key command. Here's another creative solution. Make the label background be another label using unicode squares. 2dlabels create b1 text '\u2588\u2588\u2588' color white xpos .5 ypos .7 size 64 This uses the square unicode character, hexadecimal 2588. This solution has the advantage that you can fade out this background together with the label. In order for the text label to appear on top of background label you have to create the text label after creating the background. I'd recommend making all the labels and backgrounds interactive with the 2dlabel dialog and saving them in a session which you use together with your movie script. The script will show and hide the labels that have already been made, sized, positioned. You can cut and paste the unicode square character, say from web page into the 2dlabel dialog. http://en.wikipedia.org/wiki/Box-drawing_characters This solution doesn't make it easy to make an outline around the background box. Elaine suggested that you just make another slightly bigger background in the outline color. That has the problem that the vertical outline edges are thicker than the horizontal ones if the the background is wider than it is tall. To get uniform thickness outline you could make two extra background boxes one square shorter than the normal background and slide them horizontally them to get vertical outline edges of equal thickness. Tom -------- Original Message -------- Subject: 2dlabels From: Gabriel Lander To: Tom Goddard Date: 11/19/11 6:59 PM > Hi Tom, > Again thanks for the volume tracer settings saver - it's been super helpful. > But now I have another question: > I'm currently making a movie that uses lots of labels, and for the most part the current 2dlabels create& acreate commands work really well. But for certain closeup views the text gets lost in the volume density, and I've been trying to figure out a way to get a box to show up behind the labels (like in the attached image). I've figured out I can get something like this if I use the "color key" option, and then offset the text to fit inside the box, but I can't find a "color key" chimera command that I can put it into my movie script. > I tried using the "shape rectangle" command, but it's a bit too tedious to position the rectangles exactly right for all the labels. > Any ideas? > -gabe >

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Calculating and showing the Mass center of Volume Segments
by Schmidt, Claudius 19 Nov '11

19 Nov '11

Hello, I got a volume map that I segmented in 4 parts. Now I wanted to measure how the parts are coordinated to each other. As the Axes/Planes/Centroids menu can only create planes by atoms I wanted to place atoms in the mass- center of each segment. Is there any way to realize that? Or do you have any other way to measure the angles. To explain what I'm trying to measure: Example you have 4 segments, I call them a b c d. I want to measure how the axis that is formed by a and b, forms an angle to c and d, or how ist he angle of the plane formed by a b and c compared to ab and d . All for segments are basically the same objects just turned and rotated. With best regards C. Schmidt

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D-Proline modeling in Chimera
by Raghavender Upadhyayula 19 Nov '11

19 Nov '11

I am using PyMol for modeling a peptide containing D-aminoacid (D-Proline) residue. I could invert the configuration arounf L-Proline to convert it to D-Proline. But, I want the "Phi" of the Proline to adopt a certain value. When i tried using the torsion command by selecting the bond N-CA of the D-Proline residue, there is no change at all. I want the Phi value to change from -60 deg to +60 deg and use this as the model for further analysis. Also, the "Psi" needs to fixed at 120 deg. Is it possible in any way to carry out the same steps and achieve the desired results in Chimera. Any suggestions on how to carry out this would be highly appreciated. -- U.S.Raghavender, PhD Postdoctoral Fellow SRI International 140 Research Drive Harrisonburg, VA 22802 540.438.6643

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Docking box
by George Tzotzos 18 Nov '11

18 Nov '11

Hi everybody, I'm visualising a cavity generated by CASTp. Ideally I'd like to draw and get the coordinates of a box around the cavity to use in docking simulations. Is this possible with Chimera? Your suggestions would be much appreciated. Regards George

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Structure superimposition - RMSD
by Suda Parimala Ravindran 18 Nov '11

18 Nov '11

**Hi all, I have a set of protein structures (about 10) that I need to superimpose. I have used Matchmaker and superimposed by choosing a reference structure. I want to know how to calculate the overall RMSD of the superimposed structures? Where do I lokk out for it? I have checked the Reply log window, but it gets displayed only for some, whereas for others it does not. Please help.. Thanks, -Suda

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