November 2011 - Chimera-users - RBVI Mailing Lists

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 18 Nov '11

18 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 17 Nov '11

17 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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Alignment
by bodvael email 15 Nov '11

15 Nov '11

Hi, I have never used Chimera so please bear with me. I have this short peptide sequence (8 aa) that I want to locate in the secondary structure of a protein which I have opened in chimera. Is there a way to highlight the sequence in a particular color in the 3D model and/or only have the aminoacid numbering in this region? Also, I would like to view a linear alignment of the entire protein sequence with my peptide sequence of interest. I was able to do that and see that the peptide sequence falls in a beta-sheet (green color). Is there any way know which strand it is exactly? It is supposed to be in strand 5 but I don't know how to display strand numbers, or verify with certainty that it is indeed strand 5 and not strand 6 for example. Thanks, Bodvael

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van der Waals surface volume
by Jacob Alan Spooner 15 Nov '11

15 Nov '11

Hello chimera-users, I am wondering if and how I can get a volume for the van der Waals surface of my molecule. I know how to generate the vdw surface, and also how the volume and surface area for the solvent excluded surface, however the same method does not seem to work for the vdw surface as it does not show up in my model panel. I tried setting the probe radius of the MSMS to zero but it does not allow this so I am stumped on how I could obtain the volume of my vdw surface. Thanks in advance Jake Spooner

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Chimera issue
by Jason Mears 15 Nov '11

15 Nov '11

I installed Chimera on my linux machine, and there is an issue when I try to open a session (See attached img). It tells me that I need to update the graphics card, but my card is new and I would think is more than sufficient to run Chimera. Any suggestions? Thanks. - Jason -- Dr. Jason Mears Assistant Professor Department of Pharmacology 216-368-3348 jason.mears(a)case.edu <mears.jason(a)case.edu>

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custom label size
by Francesco Pietra 13 Nov '11

13 Nov '11

Hello: Is it possible to increase the letter size of custom labels? I would like to show the residue number only, saving as a stereo pair. As my stereo pair (a protein complex) works nicely for most people only at a reduced size of the figure (14x4 centimeters, or even smaller), larger letter-size is needed for the labels. thanks francesco pietra

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