May 2015 - Chimera-users - RBVI Mailing Lists

Acylation of peptide
by Remmer Salas 08 May '15

08 May '15

Hi! I am new to Chimera and I am trying to modify the PDB file of a peptide by acylation. I have also a PDB file for the fatty acid which I got by removing the bound protein. I used the join models to form a peptide bond but prompted with this error: The following problems occurred while reading PDB file for anomt1.pdbStart residue of secondary structure not found: HELIX 1 1 LEU 2 LEU 10 1 8Model 1 (anomt1.pdb) appears to be a protein without secondary structure assignments.Automatically computing assignments using 'ksdssp' and parameter values: energy cutoff -0.5 minimum helix length 3 minimum strand length 3Use command 'help ksdssp' for more information.TypeError Exception in Tk callback Function: <bound method BuildStructureDialog._addParamBond of <BuildStructure.gui.BuildStructureDialog object at 0x04F9FBF0>> (type: <type 'instancemethod'>) Args: ()Traceback (innermost last): File "C:\Program Files\Chimera 1.10.1\bin\lib\site-packages\Pmw\Pmw_1_3_3\lib\PmwBase.py", line 1747, in __call__ return apply(self.func, args) File "C:\Program Files\Chimera 1.10.1\share\BuildStructure\gui.py", line 313, in _addParamBond self._appbDihedral.get(), phi=self._appbPhi.get()) File "C:\Program Files\Chimera 1.10.1\share\BuildStructure\__init__.py", line 869, in cnPeptideBond cn[1].residue.phi = phi File "C:\Program Files\Chimera 1.10.1\share\chimera\phipsi.py", line 91, in setPhi _setAngle(bond, phi, getPhi(res), "phi") File "C:\Program Files\Chimera 1.10.1\share\chimera\phipsi.py", line 134, in _setAngle br.angle = (newAngle - curAngle, br.biggerSide())TypeError: unsupported operand type(s) for -: 'float' and 'NoneType' TypeError: unsupported operand type(s) for -: 'float' and 'NoneType' File "C:\Program Files\Chimera 1.10.1\share\chimera\phipsi.py", line 134, in _setAngle br.angle = (newAngle - curAngle, br.biggerSide()) My first question is how to solve this error. Second, how can I optimize the generated PDB file using Chimera? I want also to convert this optimize PDB file to PQR. Any advice is greatly appreciated.

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clip planes
by Bharat Lakhani 08 May '15

08 May '15

Dear All I want to visualize the core of my protein, Is it possible to slice the protein right into two half in order to visualize the core of the protein. I tried using chimera pre-capping model but it has not been work out well. Any suggestion on this would be great. Thanks

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Coloring selected residues based on B-factor
by Mahendra B Thapa 07 May '15

07 May '15

Dear Chimera users, While using Chimera to study a protein with 511 residues, I colored residues 1- 274 'dark grey', residues 274-417 'tan' and residues 418-511 'dark khaki'. I want to color residues, say, 313,350,412,415,485,503, from blue to red with an increasing order of B-factors, say respective B-factors are 40,13,2,21,33,6 without altering the color of other residues. I manually put these B-factors values for the corresponding residues; rest residues have no b-factor values as the structure is obtained from a simulation. I tried some unsuccessful attempts visiting some previous posts (sorry if I missed such posts close to my query). Any comments and suggestions might help me. Thank you, Mahendra Thapa University of Cincinnati,OH

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aborting a volume command
by Dougherty, Matthew T 07 May '15

07 May '15

I issued this command, which works correctly. volume #2 planes z,1,100,1,10 I try to abort it around slice 50 using freeze, which does not terminate. Is there a way to abort it? Matthew Dougherty National Center for Macromolecular Imaging Baylor College of Medicine ===========================================================================

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Displaying and calculating protein surface enclosed pockets
by Matthias Fellner 07 May '15

07 May '15

Good day I am a PhD student at the University of Otago New Zealand. First I would like to thank you for this very useful software, I use it for all my protein crystallography pictures and a lot of analysis as well, I always cite your citation for sure when I publish using your software. Normally I get very far with your tutorials but this time I failed to achieve my goal and I wanted to write a direct question. I have a protein with an active site pocket. I can display the surface of the protein and then I see the pocket inside but I am really interested in the enclosed surface = the active site pocket. How can I display the "negative" (enclosed) surface area and possibly calculate its volume. Can this be done with the pdb file or is such an analysis only possible based on the electron density. I learned how to manipulate the density map in chimera, so if this is the only way I should also be able to do it if you explain the details. If I get this done I wanted to ask if there is a way to ignore water molecules from the displaying of surfaces and later calculations or if I should simply work with a pdb which has the waters removed. Thank you Matthias Fellner

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listen selection command
by Mungo Carstairs (Staff) 07 May '15

07 May '15

Hi, I am trying out a REST listener for selections in Chimera and need help. I can talk to Chimera over REST. I can start an Http listener in Jalview - and verify it in my browser. I have sent this command to Chimera: listen start selection rest http://134.36.162.131:64745/ Then silence. I haven't managed to provoke Chimera into sending me a SelectionChanged notification. I am making selections in the Chimera window - as I can see by the 'Inspect Selection' panel. I have also started Chimera standalone (no REST service) and tried the listen command in the command line, but yet to see any output on a selection. What have I missed or how can I diagnose what I am doing wrong here? Thanks, Mungo Carstairs Jalview Computational Scientist The Barton Group Division of Computational Biology College of Life Sciences University of Dundee, Dundee, Scotland, UK. www.jalview.org<http://www.jalview.org/> www.compbio.dundee.ac.uk<http://www.compbio.dundee.ac.uk/> The University of Dundee is a registered Scottish Charity, No: SC015096

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Re: [Chimera-users] [chimera-dev] VolumeEraser
by Tom Goddard 06 May '15

06 May '15

Hi Alex, Surfnet in Chimera does not produce a volume, only surfaces. It calculates the volume but then computes surfaces and deletes the volume. If you would to measure the enclosed volume of the disconnected pieces produced by surfnet, first make those pieces independently selectable with command sop split #0 where #0 is the id for the surfnet model (use Favorites / Model Panel to find the correct id number). Then select the piece of interest (ctrl click on it), then get its enclosed volume with command measure volume sel To type commands to Chimera use menu Favorites / Command Line. This question belongs on the chimera-users mailing list, not the chimera-dev list which is for programming issues. Tom > On May 6, 2015, at 8:18 AM, Alex wrote: > > Dear Sirs, > I recently started using chimera, please apologise my lack of knowledge. > In order to erase a surfnet volume I am trying to use the Erase volume module, but it doesn't work. Are the surfnet objects available to be used in VolumeEraser functions? Is there another way to study volume intersections? > If you know, please point out the article which describes the procedure for this kind of volume calculation. > > Best regards, > Alex > _______________________________________________ > Chimera-dev mailing list > Chimera-dev(a)cgl.ucsf.edu <mailto:Chimera-dev@cgl.ucsf.edu> > http://plato.cgl.ucsf.edu/mailman/listinfo/chimera-dev <http://plato.cgl.ucsf.edu/mailman/listinfo/chimera-dev>

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PC shut down automatically while using Chimera
by kzhang＠mrc-lmb.cam.ac.uk 06 May '15

06 May '15

Dear Chimera Developers, Recently, I found something really annoying when I was using Chimera. The problem is that when I use chimera to display CryoEM maps(400X400X400, 32 bits), my computer shut down automatically. I don't think there's something wrong with the hardware and coot or pymol is fine. This is not just an accident. It happened quite a few times, especially when I suddenly zoom in, computer is suddenly shut down. Later there would be some error massage related to the instability of the power, CPU self protection "£$%^&# ... when I turned on the computer again. But I don't think there is anything wrong with the power as well, I've run other softwares without any problem. Also, it happens to both Window 7 and CentOS 6.5 in the same PC. So it's obviously hardware level issue related to Chimera. My guess is that there might be something in Chimera that activated the self-protection of CPU or similar things. Any ideas why this occurs and how can I solve it? Best wishes Kai

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imod
by Dougherty, Matthew T 04 May '15

04 May '15

I have recently been getting some imod segmentation files and have been noticing three problems 1) when I read the MRC and imod files I am having a scaling problem, and the datasets do not integrate. For example, if the MRC voxel size is 31.22 31.22 31.22, and the origin index is 0 -114 0, I have to change the the voxel size to 3.122 3.122 3.122 , and the origin index to 0 0 0 so that graphics match correctly. Since there are number of people in the data chain before it gets to me, I thought it might check to determine if this is known problem before going upstream to unknown people to figure out if they are getting the imod output settings correct. 2) The graphics performance with imod segmentation files is sluggish in chimera, not sure what it is in imod. I assume that the format defines the vertices at the highest resolution corresponding with the MRC file. Is there a way to improve the performance on the chimera side? I am not using contouring, just reading the file in default mode. 3) The segmentation has a lot of components, such as vesicles and microtubules, that have different colors. Is there a way to break apart the components so they can be manipulated seperately? E.g., display/hide, change colors, translate and rotate. Matthew Dougherty National Center for Macromolecular Imaging Baylor College of Medicine ===========================================================================

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running script + recording movie
by Dmitry 04 May '15

04 May '15

Dear colleagues, Does anybody know how to run the script in chimera - *.cmd (from windows) and in the same time record everything that script does as a movie? Sincerely, Dmitry

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