- Chimera-users - RBVI Mailing Lists

Structure editing
by George Tzotzos 02 Jul '14

02 Jul '14

I’m dealing with a X-ray model in which some of the residues are shown in two conformations. Is it possible to edit the structure keeping the higher occupancy conformation ONLY? Another question is whether it is possible to delete all waters but the selected ones (e.g. HOH molecules in the binding pocket that are conserved). I’ve been doing this manually using an editor and I wonder if there is better way of doing this. Thanks in advance for your advice Regards George

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suggested improvements
by Dougherty, Matthew T 02 Jul '14

02 Jul '14

1) first suggestion on the sym command the following is defined icosahedral symmetry I[,orientation] around center Example: i,n25 where orientation can be: 222 (default) - with two-fold symmetry axes along the X, Y, and Z axes 2n5 - with two-fold symmetry along X and 5-fold along Z n25 - with two-fold symmetry along Y and 5-fold along Z 2n3 - with two-fold symmetry along X and 3-fold along Z 222r - same as 222 except rotated 90° about Z 2n5r - same as 2n5 except rotated 180° about Y n25r - same as n25 except rotated 180° about X 2n3r - same as 2n3 except rotated 180° about Y In the chimera tool->higher order structure -> the icosahedral structure it defines similar orientations, assume in the same order. It would be helpful on the selections to include the sym syntax as part of the icosahedral structure text ie {222} xyz 2 fold {2n5} x 2 fold z 5 fold 2) second suggestion When reading an MRC file I occasionally see situations that make me question whether the file is EMDB complaint. It would be good to have the means to dump the MRC header, even if chimera refuses to read the file in its entirety. Matthew Dougherty National Center for Macromolecular Imaging Baylor College of Medicine ===========================================================================

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Re: [Chimera-users] Attaching a Probe to Modify an Existing Amino Acid
by Eric Pettersen 02 Jul '14

02 Jul '14

Hi Shana, Well, you might be able to get away with just setting that atom's "name" attribute to "SD", but since you are writing Python code anyway and residues hold their atoms in a name-indexed structure, it would be better to do it the right way by removing the atom from the residue, renaming it, and putting it back. Assuming you have the CYS residue in a variable named 'cys': s = cys.findAtom("SG") cys.removeAtom(s) s.name = "SD" cys.addAtom(s) --Eric On Jun 19, 2014, at 11:25 AM, Shana Burstein <sburstei(a)haverford.edu> wrote: > Hi Eric, > I was able to move the CN atoms from the CN residue to the CYS residue and call it MSCN. I actually need it to be called MSCN in order for the modified residue to be recognized by a force field in an MD simulation. My only problem now is that the S atom of cysteine is labeled as "SG" and I need it to be called "SD." I know how to do this by going through the Tool menu, but is there a way to automate that? > > Thanks, > Shana > > > On Wed, Jun 18, 2014 at 2:35 PM, Eric Pettersen <pett(a)cgl.ucsf.edu> wrote: > Hi Shana, > If you were starting from scratch, the procedure to add the CN would probably be simpler by using chimera.molEdit.addDihedralAtom() to add the C and then the N at the appropriate bond length, angle and dihedral and then rename the residue with: r.type = "MSCN". Nonetheless, you have come a long way down the road with your script and probably would not prefer to start over from scratch! So let's suppose you have your two relevant Residue instances in variables named 'cys' and 'cn'. The code to do what you want would be: > > for a in cn.atoms: > cn.removeAtom(a) > cys.addAtom(a) > cys.type = "MSCN" > # empty residues are problematic in various parts of Chimera, so... > cn.molecule.deleteResidue(cn) > > If you don't know how to get the 'cys' and 'cn' variables but you know an atom specifier that selects each, you can use this code to set the variables: > > runCommand("sel atom-spec-for-cys") > cys = chimera.selection.currentResidues()[0] > runCommand("sel atom-spec-for-cn") > cn = chimera.selection.currentResidues()[0] > > There's a couple of further relevant things here. Strictly speaking, 4-letter residue names are not legal in PDB format (while there is a column where a 4th character could go, according to the format definition that column is supposed to be blank). Therefore if you export your modified structure to other software programs, they may or may not be able to handle the 4-character residue name without problems. Therefore I recommend you use the same residue name that the PDB uses for this moiety, 4CY (which can be found in the 3or0 entry). > Along the same lines, 4CY can actually be found in the SwissSidechain rotamer library plugin for Chimera (SwissSidechain - A database of non-natural side chains) and therefore if you install that plugin then the entire substitution process becomes a single command: swapnaa 4CY cysteine-atom-spec. > > --Eric > > Eric Pettersen > UCSF Computer Graphics Lab > http://www.cgl.ucsf.edu > > On Jun 18, 2014, at 6:50 AM, Shana Burstein <sburstei(a)haverford.edu> wrote: > >> Hello, >> I am an undergraduate student at Haverford College and I am attempting to attach thiocyanate probes onto different sites along a protein by first replacing the existing amino acid with a cysteine and then by adding a C and N onto the S- of the Cys residue. I know it is possible to carry this out manually using Tools>Structure Editing>Modify Structure, but I am hoping to automate this process by calling an external .py script that will primarily contain a list of preexisting Chimera commands. >> >> I have been successful at converting the targeted amino acid to Cys using "swapaa," building a CN residue called MSCN (using the createMolecule.py as a guide), combining the two models into one ("combine selected close True") and forming a bond between the Cys S and CN C atoms ("bond"). >> >> At this point, I am seeking help in automating the renaming of the modified residue to MSCN. Currently, Chimera sees this residue as two different separate residues called CYS and MSCN. Is there a way to combine these two structures so that the label corresponds to MSCN and the residue number corresponds to CYS? >> >> Sincerely, >> >> Shana Burstein >> Haverford College '15 >> _______________________________________________ >> Chimera-users mailing list >> Chimera-users(a)cgl.ucsf.edu >> http://plato.cgl.ucsf.edu/mailman/listinfo/chimera-users > > > >

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Making a hole in a volume
by Dieter Blaas 01 Jul '14

01 Jul '14

Hi, I am trying to make a small hole in a volume with 'erase octant' but either it cuts away some of the volume at the wrong place or the hole created is much bigger than the green box. Sometimes it does not do anything until I make the box bigger. What might I am doing wrong ? (chimera 1.6.2) Thanks, Dieter ------------------------------------------------------------------------ Dieter Blaas, Max F. Perutz Laboratories Medical University of Vienna, Inst. Med. Biochem., Vienna Biocenter (VBC), Dr. Bohr Gasse 9/3, A-1030 Vienna, Austria, Tel: 0043 1 4277 61630, Fax: 0043 1 4277 9616, e-mail: dieter.blaas(a)meduniwien.ac.at ------------------------------------------------------------------------

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Re: [Chimera-users] Fo-Fc electron density maps
by Oliver Clarke 30 Jun '14

30 Jun '14

Actually adding a second arg works well, thanks! So now I have: alias normalize_to_rms vop scale $1 rms 1 modelID $2; close $1; volume $2 capfaces false style mesh meshlighting false squaremesh false color blue; sop cap off alias split_diff_map vop scale $1 rms 1 modelID $2; close $1; volume $2 capfaces false style mesh meshlighting false squaremesh false level -3 color red level 3 color green; sop cap off Where the first one just normalizes to rms and colors blue, and the second one also normalizes but creates two appropriately colored contours, and I can call these as e.g. split_diff_map #0 #1, where #0 is the input map number and #1 is the desired output map number. Cheers, Oliver. On Jun 30, 2014, at 5:06 PM, Tom Goddard <goddard(a)sonic.net> wrote: > Making a macro create map #1000 does not work well, since the second time you use it it will try to make another model #1000. You could add a second argument to your macro that specifies the output model number. Or you make your macro that sets all the volume settings (mesh, capfaces, …) take a model number. None of the choices is very good. > > Tom > > On Jun 30, 2014, at 2:01 PM, Oliver Clarke <olibclarke(a)gmail.com> wrote: > >> Ah right - that’s okay then, I can just assign it to modelID 1000 then, on the assumption that I’ll never have 1000 models open at the same time. >> >> Thanks! >> >> Oliver. >> On Jun 30, 2014, at 4:59 PM, Tom Goddard <goddard(a)sonic.net> wrote: >> >>> There is no special variable to indicate the last created map for use in Chimera commands. In a vop command you can include an option “modelId #5” to assign the id number of the new model. So your macro could take the model id you want for the new map. If you use the vop (volume operation) command to create a new map and don’t specify the modelId option then the new map has the lowest unused model number. There are no output values assigned to variables in the Chimera command language, so it is quite limited. >>> >>> Tom >>> >>> >>> On Jun 30, 2014, at 11:32 AM, Oliver Clarke wrote: >>> >>>> Thanks Tom and Elaine, that’s very helpful! >>>> >>>> While we’re on the topic of macros/aliases, is there any way to refer to the model ID of an output map of a command as a variable in an alias? >>>> >>>> For example, in the normalize_to_rms macro below, I would prefer to apply all the volume settings to just the map I am normalizing, rather than all open maps, but I can’t predict the model ID of the output map because it depends on how many maps I have open. >>>> >>>> This would be handy for stringing together multiple map/model manipulations in a single macro - e.g. to normalize a map to rms, generate two contours and color them appropriately, without disturbing any other open maps. >>>> >>>> Cheers, >>>> Oliver. >>>> >>>> On Jun 30, 2014, at 2:00 PM, Tom Goddard wrote: >>>> >>>>> Hi Oliver, >>>>> >>>>> To simplify your Chimera macros a bit you can put multiple options in one volume command. Instead of >>>>> >>>>> volume # capfaces false; volume # style mesh; volume # meshlighting false; volume # squaremesh false >>>>> >>>>> you can change settings for all open maps with >>>>> >>>>> volume # capfaces false style mesh meshlighting false squaremesh false >>>>> >>>>> Tom >>>>> >>>>> >>>>> On Jun 28, 2014, at 3:14 PM, Oliver Clarke wrote: >>>>> >>>>>> Dear Egor, >>>>>> >>>>>> In addition to Elaine’s suggestion of unchecking “Cap high values at box faces", I use the following aliases to make difference maps more familiar in style to a crystallographer: >>>>>> >>>>>> First, to just normalize the map to RMS (as per coot etc) and adjust to get a mesh, turn capping, mesh lighting off etc: >>>>>> >>>>>> alias normalize_to_rms vop scale $1 rms 1; close $1; volume # capfaces false; sop cap off; volume # style mesh; volume # meshlighting false; volume # square mesh false >>>>>> >>>>>> Second, to split the map into two maps (one positive, one negative), which can then be colored green and red respectively: >>>>>> >>>>>> alias split_diff_map vop threshold $1 minimum 0; vop threshold $1 maximum 0; close $1; sop cap off; volume # style mesh; volume # meshlighting false; volume # squaremesh false; >>>>>> >>>>>> I add these two lines in a “chimera_aliases.com” file, which you can tell Chimera to read at startup under Favorites—>Preferences—>Command Line. >>>>>> >>>>>> You can then run these commands from the chimera command line, e.g. normalize_to_rms #1 or split_diff_map #1 if your map number is 1. Then just adjust the contours and colors in the volume viewer and you are good to go. >>>>>> >>>>>> I don’t know how to automatically color the resultant maps, because there does not seem an obvious way to predict their model numbers, but I am sure there is a way to do that too, perhaps via some python trickery. >>>>>> >>>>>> This is all kind of a work around of course - there may be a way to color a map by density value (such that all positive regions are green, and all negate regions are red), but I couldn’t figure out how to do it. >>>>>> >>>>>> Best, >>>>>> Oliver. >>>>>> _______________________________________________ >>>>>> Chimera-users mailing list >>>>>> Chimera-users(a)cgl.ucsf.edu >>>>>> http://plato.cgl.ucsf.edu/mailman/listinfo/chimera-users >>>>>> >>>>> >>>> >>>> >>> >> >> >

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Re: [Chimera-users] Fo-Fc electron density maps
by Oliver Clarke 30 Jun '14

30 Jun '14

Dear Egor, In addition to Elaine’s suggestion of unchecking “Cap high values at box faces", I use the following aliases to make difference maps more familiar in style to a crystallographer: First, to just normalize the map to RMS (as per coot etc) and adjust to get a mesh, turn capping, mesh lighting off etc: alias normalize_to_rms vop scale $1 rms 1; close $1; volume # capfaces false; sop cap off; volume # style mesh; volume # meshlighting false; volume # square mesh false Second, to split the map into two maps (one positive, one negative), which can then be colored green and red respectively: alias split_diff_map vop threshold $1 minimum 0; vop threshold $1 maximum 0; close $1; sop cap off; volume # style mesh; volume # meshlighting false; volume # squaremesh false; I add these two lines in a “chimera_aliases.com” file, which you can tell Chimera to read at startup under Favorites—>Preferences—>Command Line. You can then run these commands from the chimera command line, e.g. normalize_to_rms #1 or split_diff_map #1 if your map number is 1. Then just adjust the contours and colors in the volume viewer and you are good to go. I don’t know how to automatically color the resultant maps, because there does not seem an obvious way to predict their model numbers, but I am sure there is a way to do that too, perhaps via some python trickery. This is all kind of a work around of course - there may be a way to color a map by density value (such that all positive regions are green, and all negate regions are red), but I couldn’t figure out how to do it. Best, Oliver.

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Calculating ASA for side chain
by saadraza＠bs.qau.edu.pk 29 Jun '14

29 Jun '14

Respected Admin I would like to know if there is any way to modify the calculation of Accessible Surface Area (ASA) to calculate only the ASA for the side chain or a particular group of atoms in chimera. If not possible could someone guide me to some other tool. I will be obliged if someone sort this problem for me Regards Saad Raza

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Fo-Fc electron density maps
by Egor Tchesnokov 28 Jun '14

28 Jun '14

Hello, Is there a way to display Fo-Fc electron density maps so that "red/negative" and "green/positive" densities are displayed at the same time. Thank you Egor

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Urgent: surface calculus
by Olivier Sire 27 Jun '14

27 Jun '14

Hello, I am in a hurry to generate a surface object with 2FJG complex to be exported in a STL format for 3D printing. This item will be presented for a local event organized by the Ligue contre le Cancer. I have download Chimera as absolute beginner and I am facing a need for splitting the (too big ?, multi-chain) complex. The function Action / Surface / show generates the splitting solution. Could you help me and guide me ? Thanks in advance Regards Olivier Sire -- *Olivier SIRE * / Professeur à l'Université de Bretagne-Sud / ------------------------------------------------------------------------ Laboratoire d'Ingénierie des Matériaux de Bretagne Campus de Tohannic BP575 56017 VANNES cedex Tél. 02 97 01 71 48 Fax. 02 97 01 70 70 Mob. 06 89 48 25 24 olivier.sire(a)univ-ubs.fr UNIVERSITÉ DE BRETAGNE-SUD http://www-limatb.univ-ubs.fr/ <http://www.univ-ubs.fr/>

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Build a quadruplex
by sette＠uniroma2.it 26 Jun '14

26 Jun '14

Dear all, Im interested to create a rough model of a quadruplex molecule using a specific sequence. One possibility could be to load a pdb structure of a quadruplex and « mutate » each nucleotide with the correct one. Is this feasible with Chimera ? Alternative suggestions are appreciated as well. Thanks for your help, Marco Dr.Marco Sette, Ph.D. Department of Chemical Sciences and Technology University of Rome, "Tor Vergata" via della Ricerca Scientifica, 00133, Rome, Italy e-mail: sette(a)uniroma2.it e-mail: m77it(a)yahoo.it Tel.: +39-0672594424 Fax: +39-0672594328 www.rete29aprile.it ---------------------------------------------------------------- Invito da parte dell'Ateneo: Il tuo futuro e quello della Ricerca Scientifica hanno bisogno del tuo aiuto. Dona il 5 x mille all'Universita' di Roma Tor Vergata codice fiscale: 80213750583 http://5x1000.uniroma2.it

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Rainbow by secondary structural element?
by Oliver Clarke 26 Jun '14

26 Jun '14

Hi all, Currently, the rainbow function can operate at the levels of per residue, per chain or per model. I was wondering whether it would be feasible in a future release to add an additional level, coloring per secondary structural element? This would be particularly handy for structures of membrane proteins, where it is often desirable to color each helix/strand a different color, while not varying the color along the helix (and not coloring residues in loops etc). Even better would be to have separate “rainbow helix” “rainbow strand” and “rainbow secstruc” commands for finer control, but this is probably not really necessary. Cheers, Oliver.

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Color by height from surface?
by Oliver Clarke 25 Jun '14

25 Jun '14

Hi all, I’m wondering if there is any way to use scolor to color by height from another surface rather than from a plane, axis or point? Specifically, I’d like to color a molecular surface by distance from the surface of the low-res model generated using multi-scale models, in order to highlight cavities in the surface of the protein. Best, Oliver.

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Chimera scripting with --nogui can't write pdb files
by rswett＠chem.wayne.edu 24 Jun '14

24 Jun '14

Hey guys, i've been trying to put together a command line only set of scripts that will do some selection processing and save a pdb without going through the gui. If I use the command chimera --nogui --script close.py pdb1.pdb pdb2.pdb where close.py contains select #0 za<3 & #1:HOH write selected 1 output.pdb I should get the residues that match that selection criteria saved as the pdb output.pdb, correct? I get SyntaxError: invalid syntax for line 2 even though this works OUTSIDE a script. as in, if I just run chimera command line and enter those commands sequentially, it works. I also noticed that within the gui I need "#1" and outside it only works with '1" as the model number. I've also tried doing this with a python script: chimera --nogui --nostatus --script "close.py pdb1.pdb pdb2.pdb output.pdb" this should pass whatever I enter as $1 $2 $3 as arguments to my script, correct? So close.py for this version contains open (sys.argv[1]) open (sys.argv[2]) select #0 za<3 & #1:CVX write selected 1 (sys.argv[3]) which also pukes on the pdb write. I couldn't find any other way to write a pdb using python syntax, I assume the way i'm doing it is wrong, but I couldn't find a write.pdb function during my digging. Does anyone have suggestions for writing a pdb based on a selection without going through the gui? I plan on batching this up for a huge number of files and directories and going through the gui would be far too time consuming. Rebecca

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making capsid map from asymmetry unit.
by Jian Guan 24 Jun '14

24 Jun '14

Dear All, I want to make a capsid map from asymmetry unit. The PDB ID is 3iyj, the L1 protein of BPV. The BPV is a T=7, icosahedral capsid. Does anybody know how to make it? Thanks a lot. Sincerely yours, Jian

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side view crash
by m.maletta＠nki.nl 23 Jun '14

23 Jun '14

Dear all, I installed the latest stable Chimera 1.9 on a 64bit ubuntu precise 12.04 and I noticed that every time I try to use the side-view applet, in the viewing control, Chimera just crash. Other function seems to work just fine. I should add that on the same machine the Chimera 1.6 does not crash. Can anyone share a similar experience in Linux? chimera Segmentation fault (core dumped) Any hint what may be the problem? Best Max __________________________________ Massimiliano Maletta post-doc in NKI Netherlands Cancer Institute -Antoni van Leeuwenhoek Hospital Plesmanlaan 121 B6 1066CX Amsterdam group of Peter Peters www.nki.nl/research/peters/ | www.necen.nl m.maletta(a)nki.nl Tel : +31 20 512 2022 Fax : +31 20 512 2029

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Icosahedral model
by 李智海 20 Jun '14

20 Jun '14

Hi， I have a density map of an icosahedral capsid, and now i want to make a icosahedral model to represent the capsid. In this model, every corner represent a capsomere. what can i do to display this in Chimera ? Do I require any plug-in? Thank you！ Best wishes! Zhihai Li School of Life Sciences, Xiamen University. Xiang'an Road(South), Xiang'an District, Xiamen City, Fujian Province, China.

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Fwd: CCL: Coordinate system rotation
by Elaine Meng 19 Jun '14

19 Jun '14

On Jun 19, 2014, at 8:33 AM, "Radoslaw Kaminski rkaminski.rk,+,gmail.com" <owner-chemistry(a)ccl.net> wrote: > Sent to CCL by: "Radoslaw Kaminski" [rkaminski.rk]=[gmail.com] > Dear All, > > A trivial question. I have a XYZ file with a molecule in some coordinate > system. I would like to have a Z axis be in a certain direction along A...B > atoms. Is there any program that can easily change my coordinate system by > choosing some 3 atoms? I can of course do all transformations by hand (for > example in Excel) but its tedious. I know that ADF is capable of transforming > the coordinates to some specified coordination system (Prof. Baerends' CCL post > from several years ago), but is there any other program that can just make such > transformations quickly? > > Thanks in advance, > Radek From: Elaine Meng <meng(a)cgl.ucsf.edu> Subject: Re: CCL: Coordinate system rotation Date: June 19, 2014 9:57:00 AM PDT Hi Radek, With Chimera you could align 2 atoms front->back and then save a PDB file with the transformed coordinates. Not sure if that is exactly what you needed, or whether it is quick enough, but you could automate looping through multiple files with a little bit of Python. (1) open XYZ file (e.g. menu File…Open, choose file.xyz, or command "open file.xyz") <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/xyz.html> <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/open.html> That will automatically assign unique atom names by element and order in file, for example the first C will be C1, the first N will be N1. (2) use "align" command to put atoms A,B in center of view along the line of sight (laboratory Z axis) with A in front and B in back (e.g.: align @c1@o1) <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/align.html> (3) save PDB with transformed coordinates (e.g. menu File…Save PDB, un-check "use untransformed coordinates" or command something like "write #0 file.pdb") <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/write.html> (4) close structure (e.g. command "close #0" or "close all") … if multiple structures to process, loop back to step 1. See here for writing looping scripts for Chimera: <http://www.rbvi.ucsf.edu/chimera/docs/ProgrammersGuide/basicPrimer.html> I hope this helps, 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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split
by John Mercer 19 Jun '14

19 Jun '14

Hi All, I understand the use of split as outlined in the tutorial describing how to find the contact region between two chains. file:///Applications/Bioinformatics/Chimera.app/Contents/Resources/share/chimera/helpdir/UsersGuide/frametut.html I don’t know the proper syntax for models with more than two chains, e. g. A, B, C, D, and E where you might like to split the model either as: A, B, D, and E in one group C in the other or A, B, and D in one group and C and E in the other. I would be grateful for a recommendation for the correct syntax to use in the argument list to form two groups to identify the contact surface after further processing (in the same manner as the tutorial). Thanks, -John

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STL Resolution Issues
by Eric Bell 19 Jun '14

19 Jun '14

Hello, I am trying to change the resolution of the atoms for a large molecule packing, but no matter how I change the zoom or the subdivisions property in the viewing effects, it seems to always produce the same filesize (~900 MB, not something our software can handle). Is this a bug or is it something that I'm doing incorrectly? I'm running on a mac, and I have tested this both with a .mol2 and .pdb file. Thanks, Eric

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how to tranfer a .mrc file to .mtz file
by #ZHANG HAIPING# 18 Jun '14

18 Jun '14

Dear chimera user: I have a .mrc file generated by chimera, now I want to convert it to .mtz formate, so I can load to coot, and examine the structure in details. Can anyone tell me how to convert .mrc to .mtz? Best regards, Haiping

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rename a residue?
by Julian Tirado-Rives 18 Jun '14

18 Jun '14

Dear Chimera team, thanks for all the work you put in into a very, very, useful program. I just have a question that I am hoping is just my inability to find the proper command ... is there a way to rename a residue before writing a PDB? I often use chimera as pre-preparation step before getting into some particular calculation packages, which often require different names for residues to indicate tautomers, protonation, etc. and it would be nice to do it from chimera rather than take the PDB's through a rather annoying set of scripts, sed's, or even text editors! Thanks in advance, - Julian - -- ----------------------------------------------------------------- | Julian Tirado-Rives | | | Department of Chemistry | Phone: (203)432-3356 | | Yale University | Fax: (203)432-6144 | | P. O. Box 208107 | email: Julian.Tirado-Rives(a)yale.edu | | New Haven, CT 06520-8107 | | -----------------------------------------------------------------

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Attaching a Probe to Modify an Existing Amino Acid
by Shana Burstein 18 Jun '14

18 Jun '14

Hello, I am an undergraduate student at Haverford College and I am attempting to attach thiocyanate probes onto different sites along a protein by first replacing the existing amino acid with a cysteine and then by adding a C and N onto the S- of the Cys residue. I know it is possible to carry this out manually using Tools>Structure Editing>Modify Structure, but I am hoping to automate this process by calling an external .py script that will primarily contain a list of preexisting Chimera commands. I have been successful at converting the targeted amino acid to Cys using "swapaa," building a CN residue called MSCN (using the createMolecule.py as a guide), combining the two models into one ("combine selected close True") and forming a bond between the Cys S and CN C atoms ("bond"). At this point, I am seeking help in automating the renaming of the modified residue to MSCN. Currently, Chimera sees this residue as two different separate residues called CYS and MSCN. Is there a way to combine these two structures so that the label corresponds to MSCN and the residue number corresponds to CYS? Sincerely, Shana Burstein Haverford College '15

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delete atoms based on their coordinates
by Aranha, Michelle 18 Jun '14

18 Jun '14

Hi , I wanted to know if there is a way in chimera to select and delete atom/atoms based on their position/coordinates in the simulation box. For example delete water 150 at (x, y, z). I tried zone sel, but I couldnt get it to work. Regards, Michelle ?

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com files & animation
by Dougherty, Matthew T 16 Jun '14

16 Jun '14

When executing a com file for animation production, I would like to see the line that is being executed display in the reply log. Is there a way to do that? I would prefer not using echo commands because of the large number of lines in the file being executed. Matthew Dougherty National Center for Macromolecular Imaging Baylor College of Medicine ===========================================================================

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Chimera Plugins
by Eric Bell 16 Jun '14

16 Jun '14

Hello, Does a list exist somewhere of plugins developed for Chimera, or would we need to find them posted separately on a host site? Also, I found recently a software that gives preset .stl mesh resolutions for all atoms of the same element so that when they are 3d-printed, the atoms can all be distinguished from one another: http://cad4.cpac.washington.edu/WinXMorphHome/Cif2VRMLHome/Cif2VRML.htm However, the rest of the software seems lacking in reference to chimera's capabilities, is there any way that Chimera could have a similar feature? Ideally it would allow the "subdivisions" property of the viewing effects apply to every element, similar to how radius applies to all atoms of the same element. Thanks, Eric

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