July 2018 - modeller_usage

Query about symmetry in a multi-chain model
by Iván Felsztyna 25 Jul '18

25 Jul '18

Hi, I'm modelling a homopentamer using two templates. I want the five subunits of my model to be as much symmetrical as possible. So, I'm using the symmetry constrains that I found in the manual. The example script was built for a homodimer, so I adapted it to my homopentamer. I also included the indications to rename the chains and renumber the residues. However, the models I obtain show important structural differences between the different chains. I can see those differences visually and also when I plot the DOPE profiles of the five chains. I want to know if there is any mistake in my script, or something that I could add to it, in order to improving my results. Thank you in advance fot you help, Iván Felsztyna # Comparative modeling by the automodel class # # Demonstrates how to build multi-chain models # from modeller import * from modeller.automodel import * # Load the automodel class log.verbose() # Override the 'special_restraints' and 'user_after_single_model' methods: class MyModel(automodel): def special_restraints(self, aln): # Constrain the A and B chains to be identical (but only restrain # the C-alpha atoms, to reduce the number of interatomic distances # that need to be calculated): s1 = selection(self.chains['A']).only_atom_types('CA') s2 = selection(self.chains['B']).only_atom_types('CA') s3 = selection(self.chains['C']).only_atom_types('CA') s4 = selection(self.chains['D']).only_atom_types('CA') s5 = selection(self.chains['E']).only_atom_types('CA') self.restraints.symmetry.append(symmetry(s1, s2, 1.0)) self.restraints.symmetry.append(symmetry(s1, s3, 1.0)) self.restraints.symmetry.append(symmetry(s1, s4, 1.0)) self.restraints.symmetry.append(symmetry(s1, s5, 1.0)) def user_after_single_model(self): # Report on symmetry violations greater than 1A after building # each model: self.restraints.symmetry.report(1.0) class MyModel(automodel): def special_patches(self, aln): # Rename both chains and renumber the residues in each self.rename_segments(segment_ids=['A', 'B', 'C', 'D', 'E'], renumber_residues=[1, 1, 1, 1, 1]) env = environ() # directories for input atom files env.io.atom_files_directory = ['.', '../atom_files'] # Be sure to use 'MyModel' rather than 'automodel' here! a = MyModel(env, alnfile='ali.ali', knowns=('a','b'), sequence=('r'), assess_methods=(assess.DOPE, assess.GA341)) a.starting_model= 1 # index of the first model a.ending_model = 100 # index of the last model # (determines how many models to calculate) a.make() # do comparative modeling

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DOPE energy plot
by Mohammad Goodarzi 24 Jul '18

24 Jul '18

Hello, I have used the standard analysis to perform homology modeling. I have two questions now 1- I want to plot the DOPE energy plot between the template and the model but after running the evaluate_model.py , I only have one TvLDH.profile. So how can I get the other profile to be able to plot this figure? 2- what other plot I can make from the outputs ? I appreciate if one can refer me to a paper or something Thanks Mohammad

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homology modeling
by Mohammad Goodarzi 24 Jul '18

24 Jul '18

Hello, I have a WT protein which I got the structure from the PDB. I have a mutation happing on a single point amino acid. I want to see how this mutation influence on specific domian. I want to know if I am doing it right or not 1- I installed modeller on a Mac (high Sierra) 2- I search for the sequence on Uniprot and then I arange it as >P1;myseq sequence:myseq:::::::0.00: 0.00 with a * at the end of sequence and save it as myfile.ali what step should I follow and or which script should I use ? Thanks, Mohammad

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Query about structural alignment of a homopentamer with salign
by Iván Felsztyna 05 Jul '18

05 Jul '18

Hi, I'm trying to use the script salign_multiple_struc.py to obtain the structural alignment of two homopentamers. I want to use them as templates for a multi-template modelling. The problem is that the fitted pdb files that I obtain include only one of the subunits of each of the homopentamers, while I need the whole protein to be aligned. I copy here the script: log.verbose() env = environ() env.io.atom_files_directory = ['.', '../atom_files'] aln = alignment(env) for (code, chain) in (('4cof_extracelular', 'A'), ('4cof_extracelular', 'B'), ('4cof_extracelular', 'C'), ('4cof_extracelular', 'D'), ('4cof_extracelular', 'E'), ('glucl', 'A'), ('glucl', 'B'), ('glucl', 'C'), ('glucl', 'D'), ('glucl', 'E')): mdl = model(env, file=code, model_segment=('FIRST:'+chain, 'LAST:'+chain)) aln.append_model(mdl, atom_files=code, align_codes=code+chain) for (weights, write_fit, whole) in (((1., 0., 0., 0., 1., 0.), False, True), ((1., 0.5, 1., 1., 1., 0.), False, True), ((1., 1., 1., 1., 1., 0.), True, False)): aln.salign(rms_cutoff=3.5, normalize_pp_scores=False, rr_file='$(LIB)/as1.sim.mat', overhang=30, gap_penalties_1d=(-450, -50), gap_penalties_3d=(0, 3), gap_gap_score=0, gap_residue_score=0, dendrogram_file='1is3A.tree', alignment_type='tree', # If 'progresive', the tree is not # computed and all structues will be # aligned sequentially to the first #ext_tree_file='1is3A_exmat.mtx', # Tree building can be avoided # if the tree is input feature_weights=weights, # For a multiple sequence alignment only # the first feature needs to be non-zero improve_alignment=True, fit=True, write_fit=write_fit, write_whole_pdb=whole, output='ALIGNMENT QUALITY') aln.write(file='1is3A.pap', alignment_format='PAP') aln.write(file='1is3A.ali', alignment_format='PIR') # The number of equivalent positions at different RMS_CUTOFF values can be # computed by changing the RMS value and keeping all feature weights = 0 aln.salign(rms_cutoff=1.0, normalize_pp_scores=False, rr_file='$(LIB)/as1.sim.mat', overhang=30, gap_penalties_1d=(-450, -50), gap_penalties_3d=(0, 3), gap_gap_score=0, gap_residue_score=0, dendrogram_file='1is3A.tree', alignment_type='progressive', feature_weights=[0]*6, improve_alignment=False, fit=False, write_fit=True, write_whole_pdb=False, output='QUALITY'). Thank you in advance for your help, Ivan Felsztyna

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Query Regarding Running Modeller From Mac
by Aparna Bahuguna 02 Jul '18

02 Jul '18

I installed modeller on Macbook Pro OS X Yosemite 10.10.5. But it does not work. I made the python files and transferred them to the bin folder in library. Then I opened terminal and gave the command: *python model-default.py > model-default.log* but it said permission denied. I installed python separately still it did not work. Kindly suggest how can I run modeller through Mac Book. -- Aparna Bahuguna c/o Prof. D. S. Rawat Department of Chemistry University of Delhi New Delhi - 110007

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Re: [modeller_usage] Query Regarding Running Modeller From Mac
by Ajasja Ljubetič 02 Jul '18

02 Jul '18

Yes, you do not need that file. Just call python file-i-have-prepaired.py Try to run the examples first. On Mon, 2 Jul 2018 at 10:31, Aparna Bahuguna <aparna.bahuguna04(a)gmail.com> wrote: > I have prepared the files. But I dont know how to prepare a > model-default.py script file. Even the example folder I downloaded did not > contain any such file. > > On Mon, Jul 2, 2018 at 1:57 PM, Ajasja Ljubetič <ajasja.ljubetic(a)gmail.com > > wrote: > >> Hi! >> >> Probably you should first go through the tutorials: >> https://salilab.org/modeller/tutorial/ >> >> Which will show you how to prepare files etc. >> >> Best, >> Ajasja >> >> On Mon, 2 Jul 2018 at 10:25, Aparna Bahuguna <aparna.bahuguna04(a)gmail.com> >> wrote: >> >>> Whenever I type the command model-default.py it says no such file or >>> directory found. How should I prepare this file. Even when I downloaded the >>> example files there was no such file found. >>> >>> On Sun, Jul 1, 2018 at 11:48 PM, Aparna Bahuguna < >>> aparna.bahuguna04(a)gmail.com> wrote: >>> >>>> I installed modeller on Macbook Pro OS X Yosemite 10.10.5. But it does >>>> not work. I made the python files and transferred them to the bin folder in >>>> library. Then I opened terminal and gave the command: *python >>>> model-default.py > model-default.log* but it said permission denied. I >>>> installed python separately still it did not work. Kindly suggest how can I >>>> run modeller through Mac Book. >>>> >>>> -- >>>> Aparna Bahuguna >>>> c/o Prof. D. S. Rawat >>>> Department of Chemistry >>>> University of Delhi >>>> New Delhi - 110007 >>>> >>> >>> >>> >>> -- >>> Aparna Bahuguna >>> c/o Prof. D. S. Rawat >>> Department of Chemistry >>> University of Delhi >>> New Delhi - 110007 >>> _______________________________________________ >>> modeller_usage mailing list >>> modeller_usage(a)salilab.org >>> https://salilab.org/mailman/listinfo/modeller_usage >>> >> > > > -- > Aparna Bahuguna > c/o Prof. D. S. Rawat > Department of Chemistry > University of Delhi > New Delhi - 110007 >

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