- Chimera-users - RBVI Mailing Lists

Mac 64-bit Chimera for large data sets
by Tom Goddard 02 Feb '10

02 Feb '10

A 64-bit Mac Chimera daily build is now available for Mac OS 10.6. It will not run on Mac OS 10.5. http://www.cgl.ucsf.edu/chimera/download.html#daily If you work with EM maps larger than 1 Gbyte or molecular models of several hundred thousand atoms the larger addressable memory in the 64-bit version will help avoid out-of-memory errors and crashes. The 32-bit Mac Chimera versions can only address 4 Gbytes of memory and because libraries, stack and other uses of memory the practical working data size limit for 32-bit versions of Chimera is about 1 Gbyte. You should have more than 4 Gbytes of memory installed in order to benefit from the 64-bit version. The 64-bit Mac Chimera is in early testing so will have more bugs than usual. I've tested the 64-bit Mac Chimera running Gaussian filtering on a 2048 by 2048 by 800 map requiring about 3.2 Gbytes for the floating point result and 0.8 Gbytes for the original map. This worked correctly (took about 3 minutes on a machine with 6 Gbytes of memory) but failed with 32-bit Mac Chimera. We are also working on a 64-bit Windows Chimera that will work with Windows 7. This may be available within a month if no serious obstacles are encountered. A 64-bit Linux Chimera has been available for a few years. Tom

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alter volume data with python
by Michael Zimmermann 02 Feb '10

02 Feb '10

Dear Chimera users, I cannot find a way to search the chimera-users archive, so I appologize if this has been asked already. I wish to alter some volume data in specific ways; delete (zero out) all volume values that do not meet certain density criteria. The following code modifies the matrix values, but I can't figure out how to update the map that is being displayed in the volume viewer. I would like to be able to do something like: opened[0].full_matrix = H Then I would only see the swath that I "selected" with the following code. # ------------------------------------------------------------------------ source = '1R0A_antigen_6A_8s_0.425f_inv.mrc' opened = chimera.openModels.open(source) em = opened[0] H = em.full_matrix() s = H.shape for k in range(0,s[2]-1): for i in range(0,s[0]-1): for j in range(0,s[1]-1): if(H[i,j,k] >= -.28) and (H[i,j,k] <= -0.001): H[i,j,k] = H[i,j,k]+1 else: H[i,j,k] = 0 # ------------------------------------------------------------------------ Thank you, -- Michael Zimmermann Ph.D. student in Bioinformatics and Computational Biology Department of Biochemistry, Biophysics and Molecular Biology Iowa State University

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SDF Partial Charges
by Nancy 01 Feb '10

01 Feb '10

Hello, I am performing protein-ligand docking simulations, and the preferred ligand input file format is Mol2. I obtained some of my ligand structures from PubChem in SDF format, and I noticed that the SDF files contain partial charges ("PUBCHEM_MMFF94_PARTIAL_CHARGES"). Is there a way to preserve the charges in Chimera when converting to Mol2 file format? Thanks in advance. Nancy

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Converting SDF to Mol2: Errors
by Nancy 01 Feb '10

01 Feb '10

Hi All, When I convert an SDF file to Mol2 format using UCSF Chimera, I noticed that some valence errors were introduced. I can correct these errors for individual molecules, but doing so for large sets becomes cumbersome; is there any solution to this problem? Thanks in advance. Nancy

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Re: [Chimera-users] [Chimera] #8137: undesirable window placement (was: Chimera bug report submission)
by Eric Pettersen 01 Feb '10

01 Feb '10

Guy Nimrod wrote: > When I do an action that opens a new window (e.g. ‘file’ -> ‘save > session as’ or ‘file’-> ‘fetch by ID’), it seems that the new window > is located in a random position. Sometimes it is out of the borders > of the screen which is very problematic. Hi Guy, I think the new window-placement behavior is an improvement for most people. Nonetheless, it seems to be a problem for you so I've changed it into a preference (with the new behavior as the default). Starting with tomorrow's daily build there will be a preference in the General category called "Try to avoid placing dialogs over main window" which you can change to "false". Unfortunately the daily build for Windows hasn't been working lately, so it may be a few days before you can get a version with this preference available... --Eric Eric Pettersen UCSF Computer Graphics Lab http://www.cgl.ucsf.edu

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Re: [Chimera-users] holle,sir!
by Elaine Meng 30 Jan '10

30 Jan '10

On Jan 29, 2010, at 10:14 PM, gytjyb wrote: > holle,sir! nice to send a letter to you! > (1) about FindHBond .I can find out some HBond between ligand and > receptor,by chimera. I also use Accelrys Discovery Studio to find > out some HBond . but Accelrys Discovery Studio find out HBond to be > more than chimera. why?which one result is ture? > (2)what is meaning about Clashes/Contacts?what is useful for Finding > Clashes/Contacts > (3)how can i find out interaction between ligand and receptor and > classify displaying. > (4)can i use this software to publicate my paper ,directly? > best wishes for you ! (1) FindHBond vs. other programs. Different programs use different methods and cutoffs, and there is no reason to expect exactly the same results. The world of science does not agree on one exact definition of H-bond. Each program should explain its own method, as we have in the FindHBond documentation. Click "Help" on the FindHBond dialog or go here: <http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/findhbond/findhbon… > Also, this same question was discussed 2 days ago on the chimera-users list, see: <http://www.cgl.ucsf.edu/pipermail/chimera-users/2010-January/004746.html > (2) What are clashes and contacts? This is explained in the Find Clashes/Contacts documentation. Click "Help" on the Find Clashes/Contacts dialog or go here: <http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/findclash/findclas… > (3) use FindHBond and Find Clashes/Contacts. The "Structure Analysis and Comparison" tutorial is one example of using these tools: <http://www.cgl.ucsf.edu/chimera/docs/UsersGuide/tutorials/ squalene.html> (4) yes, you can use images and calculation results from Chimera in your paper, but please remember to credit Chimera as described here: <http://www.cgl.ucsf.edu/chimera/docs/credits.html> 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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H Bonds in MD simulation
by snoze pa 29 Jan '10

29 Jan '10

Dear Chimera Users, I am analyzing a MD trajectory in chimera. After selecting H binds when I am playing the trajectory, then it always shows the hydrogen bond. Though some of the bonds are broken during the simulation but it always connect the step 1 h bonds connected.. How can I show the h bonds which breaks during the simulation. Thank you very much for your help. S

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Re: [Chimera-users] Rename atoms...and chains, residue numbers
by Jonathan Sheehan 28 Jan '10

28 Jan '10

On Mon, Jan 25, 2010 at 4:25 PM, Eric Pettersen <pett(a)cgl.ucsf.edu> wrote: > This is actually a little trickier than it really should be in the current > builds. As of tomorrow's daily build the following will work without any > issues to set the name of selected atoms to 'X1': > from chimera import runCommand > runCommand("setattr a name X1 sel") > --or-- > from chimera import selection > for a in selection.currentAtoms(): > a.name = "X1" Hi- Following up on this, I'd like to offer a feature request regarding structure editing. Two of the most common tasks I need to do when constructing a model are: renaming the chains in the structure, and renumbering stretches of residues. I can imagine two menu items similar to "Actions->Atoms/Bonds->Delete" named "Set chain ID..." and "Renumber residues from..." that could operate on the current selection. I suspect these menu options (or something similar, maybe under "structure editing"?) would be helpful to many folks. It could be a lot faster / easier than generating the right awk line or venturing into Emacs' PDB-mode. :-) Would this be difficult to implement? Thanks for considering it, -Jonathan -- Jonathan Sheehan, Ph.D. Comput. Biol. Educ. and Outreach Vanderbilt Univ. Ctr. for Struct. Biol. 5138 MRB3, 465 21st Avenue S. Nashville, TN 37232-8755

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Re: [Chimera-users] Chimera-users Digest, Vol 81, Issue 21 - chopped ccp4 maps in chimera
by Boaz Shaanan 28 Jan '10

28 Jan '10

Hi, The possible reason for the chopped ccp4 maps when they are displayed in Chimera (whereas they're fine Coot) may have to do with the fact that as far as I know Chimera does not apply the crystallographic symmetry operations to the ccp4 map (at least that's how it used to be in v1.3), whereas Coot does. So if the map is defined for the asymmetric unit only, it has to be expanded in order to cover all the region which one wants to display before being read into Chimera. There could of course be other reasons for the chopped maps. Cheers, Boaz ----- Original Message ----- From: chimera-users-request(a)cgl.ucsf.edu Date: Thursday, January 28, 2010 21:11 Subject: Chimera-users Digest, Vol 81, Issue 21 To: chimera-users(a)cgl.ucsf.edu > Send Chimera-users mailing list submissions to > chimera-users(a)cgl.ucsf.edu > > To subscribe or unsubscribe via the World Wide Web, visit > http://www.cgl.ucsf.edu/mailman/listinfo/chimera-users > or, via email, send a message with subject or body 'help' to > chimera-users-request(a)cgl.ucsf.edu > > You can reach the person managing the list at > chimera-users-owner(a)cgl.ucsf.edu > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Chimera-users digest..." > > > Today's Topics: > > 1. Re: Chimera movie question (Tom Goddard) > 2. Contouring ED Map: Sigma versus Chimera > thresholds (Veer Bhatt) > 3. Re: Contouring ED Map: Sigma versus Chimera thresholds > (Elaine Meng) > 4. Contouring ED Maps (Hector Viadiu) > 5. Re: Contouring ED Maps (Tom Goddard) > 6. H Bonds in MD simulation (snoze pa) > 7. Re: H Bonds in MD simulation (Elaine Meng) > > > ----------------------------------------------------------------- > ----- > > Message: 1 > Date: Wed, 27 Jan 2010 12:51:19 -0800 > From: Tom Goddard <goddard(a)cgl.ucsf.edu> > To: Bridget Carragher <bcarr(a)scripps.edu> > Cc: chimera-users(a)cgl.ucsf.edu > Subject: Re: [Chimera-users] Chimera movie question > Message-ID: <4B60A747.5030705(a)cgl.ucsf.edu> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Hi Bridget, > > I put an example animation on the Chimera web site in the > animation > gallery called "Herpes virus slices". There is also a link > to a command > script which makes this movie. You just use File/Open... > in Chimera to > run the command script. > > > http://www.cgl.ucsf.edu/chimera/animations/animations.html > Tom > > > > > > OK, thanks Tom. Any tips on how to do all three planes > at once - or > > > rather keep the others constant while eating though the side > plane. I > > > have sen movies like this but can;t seem to figure out how > to do it in > > > Chimera. > > > Bridget > > > > > > > ------------------------------ > > Message: 2 > Date: Wed, 27 Jan 2010 19:12:31 -0500 > From: Veer Bhatt <veer82(a)gmail.com> > To: chimera-users(a)cgl.ucsf.edu > Subject: [Chimera-users] Contouring ED Map: Sigma versus Chimera > thresholds > Message-ID: <C41C6E8E-343B-4FA1-BB71-49BAADB32DF2(a)gmail.com> > Content-Type: text/plain; charset="us-ascii"; Format="flowed"; > DelSp="yes" > > Hi, > This in context of using Chimera to view *ccp4 format > electron > density maps. How does Chimera 'Threshold Level' ('Level' in > Volume > viewer) equate or relate to sigma level reported by some > other > programs. For example a 'Level' of 0.4 seems like a map > contoured at > 1.5 sigma or so. > I was wondering if someone could point out how these two are > related, > more precisely. > > Thanks > > Veer Sandeep Bhatt > >

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Contouring ED Map: Sigma versus Chimera thresholds
by Veer Bhatt 27 Jan '10

27 Jan '10

Hi, This in context of using Chimera to view *ccp4 format electron density maps. How does Chimera 'Threshold Level' ('Level' in Volume viewer) equate or relate to sigma level reported by some other programs. For example a 'Level' of 0.4 seems like a map contoured at 1.5 sigma or so. I was wondering if someone could point out how these two are related, more precisely. Thanks Veer Sandeep Bhatt

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