- Chimera-users - RBVI Mailing Lists

install question
by Randy Heiland 23 Apr '04

23 Apr '04

Greetings from a newbie to Chimera, Is there a searchable archive? (I found the archive, but no associated search engine) I'd really like to be able to install Chimera without blowing away my current Python installation - is this possible? (I'll be using both Windows and Linux) Thanks, Randy

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Viewing orbitals and charge distributions
by João Otávio 23 Apr '04

23 Apr '04

Hello All! I am a CHIMERA newbie and I would like to know how could I create a module in order to read orbitals and/or charge distributions from molecular orbitals programs such as GAUSSIAN, GAMESS, etc. Thanks in advance, .................................................................João -- ___________________________________________________________ Sign-up for Ads Free at Mail.com http://promo.mail.com/adsfreejump.htm

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save session error in Chimera 1892
by Juha Huiskonen 22 Apr '04

22 Apr '04

Hi, when trying to save session in chimera 1892 I get an error: Error processing trigger "save session": ValueError: Can't convert type <type 'bool'> (see reply log for Python traceback info) Reply log: Traceback (most recent call last): File "/usr/local/chimera1892/share/__main__.py", line 56, in ? value = chimeraInit.init(sys.argv) File "/usr/local/chimera/share/chimeraInit.py", line 285, in init tkgui.eventLoop() File "/usr/local/chimera/share/chimera/tkgui.py", line 2809, in eventLoop app.mainloop() File "/usr/local/chimera/lib/python2.3/lib-tk/Tkinter.py", line 965, in mainloop self.tk.mainloop(n) File "/usr/local/chimera/lib/python2.3/site-packages/Pmw/Pmw_1_2/lib/PmwBase.py", line 1747, in __call__ return apply(self.func, args) File "/usr/local/chimera/share/chimera/baseDialog.py", line 409, in OK self.Apply() File "/usr/local/chimera/share/OpenSave/__init__.py", line 141, in Apply self.command(1, self) File "/usr/local/chimera/share/SimpleSession/gui.py", line 24, in _saveCB saveSession(paths[0]) File "/usr/local/chimera/share/SimpleSession/save.py", line 269, in saveSession chimera.triggers.activateTrigger(SAVE_SESSION, buf) File "/usr/local/chimera/share/chimera/triggerSet.py", line 214, in activateTrigger self._triggerDict[name].activate(data) File "/usr/local/chimera/share/chimera/triggerSet.py", line 127, in activate ret = handler.invoke(self._name, triggerData) File "/usr/local/chimera/share/chimera/triggerSet.py", line 82, in invoke self._funcData, triggerData) File "/usr/local/chimera/share/VolumeViewer/__init__.py", line 138, in save_session_cb session.save_volume_state(self, file) File "/usr/local/chimera/share/VolumeViewer/session.py", line 22, in save_volume_state t = objecttree.instance_tree_to_basic_tree(s) File "/usr/local/chimera/share/SessionUtil/objecttree.py", line 69, in instance_tree_to_basic_tree d[k] = it2bt(getattr(itree, attr)) File "/usr/local/chimera/share/SessionUtil/objecttree.py", line 37, in it2bt return instance_tree_to_basic_tree(it, c, a) File "/usr/local/chimera/share/SessionUtil/objecttree.py", line 72, in instance_tree_to_basic_tree raise ValueError, "Can't convert type " + str(t) ValueError: Can't convert type <type 'bool'> -- The session file is written, but it doesn't contain the files I have read into chimera. Cheers, Juha Huiskonen

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Re: [Chimera-users] chimera and hydrophobic potentials
by Thomas Goddard 12 Apr '04

12 Apr '04

Hi Miguel, If GRID computes the hydrophobic potential on a surface, it seems like a bad strategy to save it in a volume format. If you interpolate onto a slightly different surface, you will get values interpolated with zeros in the volume because the hydrophobicity wasn't computed at most grid vertices. It seems it would be better to render the hydrophobicity values with exactly the GRID surface. Can GRID output the triangulated surface with hydrophobicity values? I looked at the MSMS library. It does not look like it provides a triangulated version of the solvent accessible service needed by Chimera. It can give you the surface area contributed by each atom to the solvent accessible surface. Tom > Date: Sun, 11 Apr 2004 22:39:40 +0100 > From: Miguel Ortiz <mol(a)ysbl.york.ac.uk> > To: Thomas Goddard <goddard(a)cgl.ucsf.edu> > Subject: Re: [Chimera-users] chimera and hydrophobic potentials > > Dear Tom, > > I've tested your cns2delphi script and, as expected, it works wonderful- > ly. The problem with colouring the surface using these maps actually > comes from the fact that for the hydrophobic probe, grid only calculates > the potential on what it's called the "solvent accessible surface" and > not on the whole volume (as delphi does for electrostatics and grid for > other probes). Being this the case, the best solution would be to > render in chimera this surface (at present, msms renders the "solvent > excluded surface" defined as you said in your email) > > I will try to find out how msms renders its surfaces, because the only > difference between "solvent accessible " and "solvent excluded" is that > the first is the "surface" defined by the center of the probe, while > the second (msms one) is the contact surface between the surface of the > probe and that of the protein (as defined by the Van der Waals radii of > its atoms). And it seems to me that it shouldn't be difficult to convert > from one to the other. Or perhaps I'm wrong and it's more tricky... > > Thank you again for all your help. It has been not only useful but > also instructive. > > Best regards, > > Miguel

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Re: [Chimera-users] chimera and hydrophobic potentials
by Thomas Goddard 09 Apr '04

09 Apr '04

Hi Miguel, I wrote a conversion program cns2delphi.py that takes the k2f output and produces a delphi file and tried it on the data you sent. The delphi file is read properly by Chimera DelphiViewer and can be used to color an MSMS surface. A problem with the data you sent is that the hydrophobicity map is zero over the entire MSMS surface. There are blobs of hydrophobicity a few angstroms away from the surface but they don't touch the surface. I observed this by showing the map with the Chimera volume viewer (just use File/Open...). You can change the probe radius for generating the MSMS surface by going to Favorites/Model Panel, selecting the MSMS surface, clicking the Attributes button, changing the probe radius setting, and pressing Enter. (You need to set the surface color to a solid color before changing the radius or an error message is generated.) Unfortunately that does not push the molecular surface out uniformly -- only the surface in the cavities is pushed further from the molecule. Apparently the probe radius is the radius of a ball rolled over the molecule with standard atom radii. The MSMS surface is the surface of the region that cannot be touched by the ball. So a bigger ball does not change the surface location at protrusions. Maybe a better approach is to specify larger atom radii. Below is the cns2delphi.py Python program. It requires the Numeric Python module which is not a standard part of Python. The Python that comes with Chimera includes Numeric. You can convert k2f output to delphi format as follows. % /usr/local/chimera/bin/python2.3 cns2delphi.py 1ltlA.k2f 1ltlA.phi This creates the 1ltlA.phi file. To use the Chimera DelphiViewer extension, start Chimera, open 1ltlA.pdb, make a molecular surface with Actions/Surface/Show, start Extensions/Delphi/DelphiViewer, enter Potential File 1ltlA.phi, click the Browse button next to MSMS Surface in the Molecular surface pane so the surface is listed, then press Apply in the Molecular surface pane. This will color the surface. You can also just use File/Open... on 1ltlA.phi to see an isosurface of the hydrophobicity map. You can drag the vertical bar on the histogram shown in the volume viewer dialog to change the isosurface threshold level. Tom ----- cns2delphi.py follows. Preserve indentation since it is important in Python. #!/usr/bin/env python # ---------------------------------------------------------------------------- # Convert CNS volume to Delphi format. # # ---------------------------------------------------------------------------- # Returns matrix, xyz_origin, and xyz_step # def read_cns_file(path): f = open(path, 'r') f.readline() # First line is blank ntitle_line = f.readline() # integer number of comment lines try: ntitle = int(ntitle_line.split()[0]) except ValueError: raise SyntaxError, ('Invalid CNS comment line count on line 2: %s' % ntitle_line[:80]) for t in range(ntitle): f.readline() extent_line = f.readline() extent = split_fields(extent_line, 8, 9) try: na, amin, amax, nb, bmin, bmax, nc, cmin, cmax = map(int, extent) except ValueError: raise SyntaxError, 'Invalid CNS grid size line: %s' % extent_line[:80] cell_line = f.readline() cell = split_fields(cell_line, 12, 6) try: cell_params = map(float, cell) except ValueError: raise SyntaxError, ('Invalid CNS cell parameters line: %s' % cell_line[:80]) cell_size = cell_params[0:3] cell_angles = cell_params[3:6] axis_order_line = f.readline() # Must be ZYX asize, bsize, csize = (amax - amin + 1, bmax - bmin + 1, cmax - cmin + 1) if asize <= 0 or bsize <= 0 or csize <=0: raise SyntaxError, ('Bad CNS grid size (%d,%d,%d)' % (asize, bsize, csize)) import Numeric data = Numeric.zeros((csize, bsize, asize), Numeric.Float32) for c in range(csize): read_floats(f, 1) # c section number values = read_floats(f, asize * bsize) array = Numeric.array(values, Numeric.Float32) plane = Numeric.reshape(array, (bsize, asize)) data[c,:,:] = plane f.readline() # footer - int value must be -9999 f.readline() # density average and standard dev f.close() xyz_step = (cell_size[0]/na, cell_size[1]/nb, cell_size[2]/nc) xyz_origin = map(lambda gmin, step: gmin * step, (amin, bmin, cmin), xyz_step) return data, xyz_origin, xyz_step # ----------------------------------------------------------------------------- # Read ascii float values on as many lines as needed to get count values. # def read_floats(f, count): values = [0.0] * count c = 0 while c < count: line = f.readline() if line == '': raise FileFormatError('File is shorter than expected') fields = split_fields(line, 12, 6) if c + len(fields) > count: fields = fields[:count-c] for v in map(float, fields): values[c] = v c = c + 1 return values # ----------------------------------------------------------------------------- # def split_fields(line, field_size, max_fields): fields = [] for k in range(0, len(line), field_size): f = line[k:k+field_size].strip() if f: fields.append(f) else: break return fields[:max_fields] # ---------------------------------------------------------------------------- # def write_delphi_file(path, matrix, xyz_center, scale): zsize, ysize, xsize = matrix.shape if xsize != ysize or xsize != zsize: raise ValueError, "Matrix size (%d,%d,%d) has to be the same in all 3 dimensions" % (zsize, ysize, xsize) size = xsize uplbl = delphi_record('Converted from ' + path) morelabels = delphi_record('%70s' % '') import Numeric data_flat = Numeric.ravel(matrix) data = delphi_record(floats_as_string(data_flat)) botlbl = delphi_record('') params = delphi_record(floats_as_string((scale,) + tuple(xyz_center)) + integer_as_string(size)) f = open(path, 'wb') f.write(uplbl + morelabels + data + botlbl + params) f.close() # ---------------------------------------------------------------------------- # def delphi_record(data): size_str = integer_as_string(len(data)) r = size_str + data + size_str return r # ---------------------------------------------------------------------------- # def integer_as_string(i): import Numeric return Numeric.array((i,), Numeric.Int32).tostring() # ---------------------------------------------------------------------------- # def floats_as_string(f): import Numeric return Numeric.array(f, Numeric.Float32).tostring() # ---------------------------------------------------------------------------- # def cns_to_delphi_file(cns_path, delphi_path): data, xyz_origin, xyz_step = read_cns_file(cns_path) if xyz_step[0] != xyz_step[1] or xyz_step[0] != xyz_step[2]: raise Value_Error, 'Step sizes (%.2g, %.2g, %.2g) are not the same along all axes' % xyz_step scale = 1.0 / xyz_step[0] size = list(data.shape) size.reverse() xyz_center = map(lambda o, st, sz: o + st * ((sz-1)/2), xyz_origin, xyz_step, size) write_delphi_file(delphi_path, data, xyz_center, scale) # ---------------------------------------------------------------------------- # if __name__ == '__main__': import sys if len(sys.argv) != 3: sys.stderr.write('Syntax: cns2delphi <cnsfile> <delphifile>\n') sys.exit(1) cns_path = sys.argv[1] delphi_path = sys.argv[2] cns_to_delphi_file(cns_path, delphi_path)

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Re: [Chimera-users] chimera and hydrophobic potentials
by Thomas Goddard 08 Apr '04

08 Apr '04

Hi Miguel, Send me some example k2a output and I'll send you a little Python program that will convert it into a Delphi file readable by Chimera DelphiViewer. Tom > Date: Thu, 8 Apr 2004 19:33:31 +0100 > From: Miguel Ortiz =?iso-8859-15?Q?Lombard=EDa?= <mol(a)ysbl.york.ac.uk> > Subject: Re: [Chimera-users] chimera and hydrophobic potentials > > Hi Tom, > > Thank you very much for your comments. > Part of the problem is that I don't trust the "delphi" maps that > GRID produces. Actually, I've been able to open some of them with > chimera. Other programs ablo to open such maps (like vmd) can't > open any of them. > > Yes, I've used k2a, and it works: it produces an ascii map that > looks sensible. My problem here is that my programming skills are > very reduced! I could work it out on a "model" program, but not > from scratch. Have you something like that? > > Thank you again, your answer has been very useful. > > Best regards, > > Miguel > > -- > Miguel Ortiz Lombardía > email: mol(a)ysbl.york.ac.uk > http://www.ysbl.york.ac.uk/~mol > ----------------------------------------------------------------------- > Our business in life is not to succeed, but > to continue to fail in good spirits. R.L. Stevenson >

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chimera and hydrophobic potentials
by Miguel Ortiz Lombardía 08 Apr '04

08 Apr '04

Hi, I would like to display the hydrophobic potential of a protein onto its MSMS surface. One program that calculates such potentials is GRID (from Molecular Discovery: http://www.moldiscovery.com/ ) GRID can produce the map in different formats. One of them is like delphi (grasp mode) map. This has the drawback that the map has to be 65x65x65 grid points and the grid points separation has to be an integer starting with 1 Ansgtroem. Hence, it's not appropriate for medium-big proteins. The GRID format hasn't those limitations. I can __sometimes__ read in chimera (throught the DelphiViewer) the delphi maps produced by GRID. Sometimes they are unreadable (and this seems to me more a problem with GRID than with chimera: something wrong in the header) But even when they are readable I'm not sure they are covering the region they are supposed to be covering. Does anyone know if chimera can read any other of the GRID map formats: GRID (this would be the optimal) Chem-X Frodo Insight Molcad Quanta Sybyl Otherwise: does anybody how to the kind of representation I'm looking for in any other way? Thank you for any advice! Miguel -- Miguel Ortiz Lombardía email: mol(a)ysbl.york.ac.uk http://www.ysbl.york.ac.uk/~mol ----------------------------------------------------------------------- Our business in life is not to succeed, but to continue to fail in good spirits. R.L. Stevenson

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compiling minrms on mac os10.2.8
by Chris Adams 02 Apr '04

02 Apr '04

Hi: I am also trying to get minrms on my OS10.2.8 machine. I followed the commands you recommended to Howard to get the "make" command to work. However, my ls output was not at all like what you said would happen in the message. I get this: ls -1 /usr/bin/*make /usr/bin/automake and am unable to compile the minrms program. I am not very unix savvy but am learning, perhaps you can help? thank you, Chris Adams UW-Biochemistry Madison, WI 53704

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correction re sessions
by Elaine Meng 31 Mar '04

31 Mar '04

Hello, in my previous message about saving parts of PDB files, I included some text from older replies to users, and this part about sessions is no longer true: >The command "save" (or File... Save Session As... ) doesn't save coordinates, >only how they are positioned/colored/displayed, etc. In fact, restarting >a saved session will use the original input file(s) for coordinates. Actually in the last few versions, the session files do include coordinates and do not look for the original input files. Sorry about that, Elaine

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writing out part of a PDB
by Elaine Meng 31 Mar '04

31 Mar '04

Hi Shuanghong, Question (1), surface problem: I don't think the problem where nothing happens when you type the command "surface" has been reported. Sometimes there is a delay while the surface is being calculated, but it shouldn't be terribly long. Problems have been reported in some cases, but they generally cause some sort of error message. To register a problem more formally, you could send mail to chimera-bugs(a)cgl.ucsf.edu and be sure to include what version of Chimera and what kind of computer you are using, and what structure(s) cause the problem. Question (2), writing out part of a PDB file: If you are on a **non-Windows** system, you can use the command "pdbrun" to save just the atoms that are displayed. You could display only the atoms you want by first selecting what you want to measure the distance to. Then, use Select...Zone... to select all the atoms in the region you want to write out. Then the command "show sel" will undisplay the rest of the stuff. (Or, instead of selecting you could do it all in one command, for example show :212.a za<4.5 for all atoms within 4.5 A of any atom in residue 212 of chain A. Specifying zones in the command line is described in the manual page on atom specification, which is listed in the Basic Functions index.) Next, use pdbrun (see man page using the command "help pdbrun"), for example: pdbrun nouser cat > myzone.pdb Pdbrun literally sends the information for only the displayed atoms in their displayed positions to another command, in this case "cat" to send the information to the file myzone.pdb. If you want the coordinates to be the same as in the original file, first use the command "reset." The command "save" (or File... Save Session As... ) doesn't save coordinates, only how they are positioned/colored/displayed, etc. In fact, restarting a saved session will use the original input file(s) for coordinates. The command "write" (same as the function "write PDB" in the Model Panel) saves coordinates into a file. However, these will save the entire coordinates whether displayed or not. If you are on **Windows** the only way I can think of is to actually delete the atoms/bonds you don't want to write out ("delete" command or Actions... Atoms/Bonds... delete). For example, when only what you want to write out is displayed, delete @/!display actually deletes the other stuff. Subsequently, a file created with "write" would only contain the atoms/bonds that had not been deleted. I hope this helps, Elaine =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Elaine C. Meng, Ph.D. Computer Graphics Lab and Babbitt Lab meng(a)cgl.ucsf.edu http://www.cgl.ucsf.edu/home/meng/index.html =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

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