August 2009 - Chimera-users - RBVI Mailing Lists

Orientation and quaternion
by Damien Larivière 06 Aug '09

06 Aug '09

Dear all, In the attached image, two copies of the FtsZ protein (pdb 1FSZ) are displayed in Chimera. I would like to know the orientation of one copy with respect to the other one. Is there a way to get this information ? Is it possible to get a quaternion instead of a set of Euler angles ? My best regards Damien

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Q about opening two structures in the same window
by Farhana F Syed 06 Aug '09

06 Aug '09

Hello, I recently downloaded chimera and have been using to view my protein homology model - mainly to show the 2 residues that could be involved in binding to a molecule inside the cell. For that purpose, I need to be able to open the small molecule (citrate or phosphate) in the same window with protein; so I can show the small molecule binds to the specific amino acid residues. But even if I open the two together, how do I pick the small molecule and move it around where I need it? Please help. Thanks, Farhana

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loading atomic coordinates without drawing or calculating bonds
by Veysel Berk 05 Aug '09

05 Aug '09

Hello, I am trying to load a large atomic coordinates file in xyz format. The atomic coordinates are meaningless to crystallography in terms of distances of atoms and as a result, while chimera try to load the coordinate and calculate the bonding between atoms, it crashes or suspends for ever. The data is from single molecule localization experiments where I want to use chimera to visualize this 3D data by treating each localization as an atom. I am trying to load about a million atoms. Is it possible to turn off automatic bonding calculations and only show atoms without bonds to prevent crashing? or does anyone know any simple method or software to convert atomic coordinates into voxel map which I can use in volume visualizer module of chimera without worrying about bond calculations? Thanks in advance, Bests, Veysel Berk

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Re: [Chimera-users] movie making
by Eric Pettersen 05 Aug '09

05 Aug '09

On Aug 5, 2009, at 2:32 AM, Schulz-Gasch, Tanja wrote: > Dear Eric, > > your movie making recommendations were indeed very helpful. Thanks > again! Hi Tanja -- glad I could help! > I am currently preparing a show for visitors at Roche that are > interested in 3D modelling and I want to do this with > Chimera. I have alreday started scripting. However, I would like to > have breaks in the scripts in case that there are > questions. So my question is, is there a possibility to implement a > prompt in the Chimera script that waits only > the users presses 'return' or whatever and then Chimera is running > further through the script? The daily build has a few things that will help here. First, there is a "pause" command that will cause a script to pause until any key other than Escape or End is pressed. Those two keys will cause the script to abort instead of continuing. Secondly, even without an explicit "pause" command any script can be paused by hitting Shift-Escape. A second Shift-Escape will continue the script. Also, plain Escape (no Shift) will cause any script to abort. I hope the presentation goes well! --Eric Eric Pettersen UCSF Computer Graphics Lab

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Stereo 3D on 120 Hz displays
by Daniel Gurnon 04 Aug '09

04 Aug '09

Just wanted to let everyone know that its finally possible to view sequential stereo in Chimera with 120 Hz LCD displays. I just confirmed that it works with my system- here's what you'll need: An appropriate Quadro card (I have a FX 4500), with the recent 190-series driver A 120Hz 3D ready LCD screen (I have the samsung 2233RZ. The other choice is a Viewsonic model) The Nvidia 3Dvision glasses kit, which includes a USB IR emitter The latest beta driver for 3Dvision, version 1.10, found here: http://www.nvidia.com/object/geforce_3D_vision_winvista_win7_CD_1.10.html Note that this only works for Vista. The 3Dvision software is supposed to only support Geforce cards, but it worked for my quadro fx 4500. After installing the drivers and the hardware I opened the Nvidia control panel 3D settings and set the following options: Stereo-Display mode: "Generic active stereo (with NVIDIA IR emitter)" Stereo-enable: "Yes" Then restart your computer, and enable sequential stereo from within Chimera. The only issue so far is that the accessory software (photo viewer and 3D preview pack) that installs with the drivers won't load; instead you get a message saying your hardware isn't compatible. ____________________________ Daniel Gurnon, Ph. D. Assistant Professor of Chemistry DePauw University Greencastle, IN 46135 p: 765-658-6279 e: danielgurnon(a)depauw.edu

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Re: [Chimera-users] Minimize
by Alex Gawronski 04 Aug '09

04 Aug '09

Hello, I'm preparing proteins for Delphi analysis using Chimera's minimize function (from a script). However this process is very time consuming. Is using minimize necessary to get accurate results from Delphi? If not, what is necessary? I've played around with the "spec" and "freeze" parameters and they either seem to have no affect or throw an error (which I submitted as a bug). What do you suggest I do? Thanks, Alex Gawronski Carleton University

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Chimera pH
by Peter Baker 03 Aug '09

03 Aug '09

I am trying to generate models of my protein at different pH. Any suggestions as to run how to accomplish this? I do have PBD2PQR files for the different pH but I am not sure how to apply them. Thanks -pjb

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transparent ring fill, color by attribute
by Elaine Meng 03 Aug '09

03 Aug '09

On Aug 3, 2009, at 2:29 PM, Alexey V. Cherepanov wrote: > Dear Elaine, > > I have another question. On the structure, I color the atoms > according to > their attribute (in my case the chemical shift differences between the > solution and the solid state NMR). I show the residues as balls & > sticks and > fill the rings of riboses & bases. Can I show the filling (i) > semitransparent, and (ii) that it keeps the colors of the atoms > (e.g. if C1' > is blue, C2' is white and C3' is red in the ribose ring, then the > filling > should be blue close to C1, white close to C2' and red close to C3' > with the > gradient in between)? > > Many thanks in advance. > Warm regards, > > Alexey Dear Alexey, The answer to your question is mostly yes, except the color in the fill is not smoothly blended. Currently it shows a "pie slice" or wedge for each ring atom. Some tricky things: (1) the ring fill automatically matches the ring atoms, so that you cannot make the fill transparent unless the atoms are also transparent. However, you can get around that problem by opening another copy of the same structure in which the atoms/bonds are opaque. (2) the transparent ring fill must not be thick. Either it must be in the "thin" style, or if in the "thick" style, the atoms and bonds in that copy must be in the wire representation (which forces it to really be thin). Why? Because some mysterious extra bonds become visible through the transparent fill when it is thick. Example: - open your structure twice - assign your attribute (e.g. use bfactor column, or Add Charge, or Define Attribute to read your own arbitrary attribute values) --- for my example, I opened 6bna twice and will use bfactor -- - use one model to make the transparent rings and the other for whatever atom/bond display you want --- I used commands: delete solvent; rep stick -- - start Render by Attribute, move the color bars as you like; for each, click the square color well, and in the Color Editor turn on "Opacity" and adjust the "A" row (transparency). There is a "Keep opaque" option, and keep that turned on and only click Apply to test the coloring. When the coloring is how you like it, then in the "Models" list at the top of the dialog, only choose one of the models. Now do not move the coloring bars, only uncheck "Keep opaque" and click Apply again. You won't be able to see any change, but now the two models are colored the same except one has the transparency and the other does not. --- I made #0 my transparent model and #1 opaque. I colored blue->red- >yellow for increasing bfactor. - now, add thin ring fill to the transparent model, command: fill thin #0 Here is the documentation for the fillring command. Today it is only at my site (tomorrow it should show up on the "real" Chimera web site). <http://www.cgl.ucsf.edu/home/meng/docs/UsersGuide/midas/fillring.html> The fillring command (or "fill" for short) is brand new and a couple things still need fixing: - to turn off filling, use ~fill ("fill off" and "fill unfilled" are not working today) - saving a session with ring fill should be available in the next daily build Here is a picture of the result:

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Chimera-users August 2009