Exemple #1
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def test_logp_reverse():
    """
    Make sure logp_reverse and logp_forward are consistent
    """
    molecule_name_1 = 'erlotinib'
    molecule_name_2 = 'imatinib'
    #molecule_name_1 = 'benzene'
    #molecule_name_2 = 'biphenyl'

    molecule1 = generate_initial_molecule(molecule_name_1)
    molecule2 = generate_initial_molecule(molecule_name_2)
    new_to_old_atom_mapping = align_molecules(molecule1, molecule2)

    sys1, pos1, top1 = oemol_to_openmm_system(molecule1, molecule_name_1)
    sys2, pos2, top2 = oemol_to_openmm_system(molecule2, molecule_name_2)
    test_pdb_file = open("reverse_test1.pdb", 'w')
    app.PDBFile.writeFile(top1, pos1, file=test_pdb_file)
    test_pdb_file.close()

    import perses.rjmc.geometry as geometry
    import perses.rjmc.topology_proposal as topology_proposal

    sm_top_proposal = topology_proposal.TopologyProposal(new_topology=top2, new_system=sys2, old_topology=top1, old_system=sys1,
                                                                    logp_proposal=0.0, new_to_old_atom_map=new_to_old_atom_mapping, new_chemical_state_key="CCC", old_chemical_state_key="CC", metadata={'test':0.0})
    geometry_engine = geometry.FFAllAngleGeometryEngine({'test': 'true'})
    new_positions, logp_proposal = geometry_engine.propose(sm_top_proposal, pos1, beta)

    logp_reverse = geometry_engine.logp_reverse(sm_top_proposal, pos2, pos1, beta)
    print(logp_proposal)
    print(logp_reverse)
    print(logp_reverse-logp_proposal)
Exemple #2
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def make_geometry_proposal_array(smiles_list, forcefield=['data/gaff.xml']):
    """
    Make an array of topology_proposals for each molecule to each other
    in the smiles_list. Includes self-proposals so as to test that.

    Parameters
    ----------
    smiles_list : list of str
        list of smiles

    Returns
    -------
    list of proposal_test namedtuple
    """
    topology_proposals = []
    #make oemol array:
    oemols = OrderedDict()
    syspostop = OrderedDict()

    for smiles in smiles_list:
        oemols[smiles] = generate_molecule_from_smiles(smiles)
    for smiles in oemols.keys():
        print("Generating %s" % smiles)
        syspostop[smiles] = oemol_to_openmm_system(oemols[smiles], forcefield=forcefield)

    #get a list of all the smiles in the appropriate order
    smiles_pairs = list()
    for smiles1 in smiles_list:
        for smiles2 in smiles_list:
            if smiles1==smiles2:
                continue
            smiles_pairs.append([smiles1, smiles2])

    for i, pair in enumerate(smiles_pairs):
        #print("preparing pair %d" % i)
        smiles_1 = pair[0]
        smiles_2 = pair[1]
        new_to_old_atom_mapping = align_molecules(oemols[smiles_1], oemols[smiles_2])
        sys1, pos1, top1 = syspostop[smiles_1]
        sys2, pos2, top2 = syspostop[smiles_2]
        import perses.rjmc.topology_proposal as topology_proposal
        sm_top_proposal = topology_proposal.TopologyProposal(new_topology=top2, new_system=sys2, old_topology=top1, old_system=sys1,
                                                                      old_chemical_state_key='',new_chemical_state_key='', logp_proposal=0.0, new_to_old_atom_map=new_to_old_atom_mapping, metadata={'test':0.0})
        sm_top_proposal._beta = beta
        proposal_tuple = proposal_test(sm_top_proposal, pos1)
        topology_proposals.append(proposal_tuple)
    return topology_proposals
Exemple #3
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def test_mutate_from_every_amino_to_every_other():
    """
    Make sure mutations are successful between every possible pair of before-and-after residues
    Mutate Ecoli F-ATPase alpha subunit to all 20 amino acids (test going FROM all possibilities)
    Mutate each residue to all 19 alternatives
    """
    import perses.rjmc.topology_proposal as topology_proposal

    aminos = [
        'ALA', 'ARG', 'ASN', 'ASP', 'CYS', 'GLN', 'GLU', 'GLY', 'HIS', 'ILE',
        'LEU', 'LYS', 'MET', 'PHE', 'PRO', 'SER', 'THR', 'TRP', 'TYR', 'VAL'
    ]

    failed_mutants = 0

    pdbid = "2A7U"
    topology, positions = load_pdbid_to_openmm(pdbid)
    modeller = app.Modeller(topology, positions)
    for chain in modeller.topology.chains():
        pass

    modeller.delete([chain])

    ff_filename = "amber99sbildn.xml"
    max_point_mutants = 1

    ff = app.ForceField(ff_filename)
    system = ff.createSystem(modeller.topology)
    chain_id = 'A'

    metadata = dict()

    system_generator = topology_proposal.SystemGenerator([ff_filename])

    pm_top_engine = topology_proposal.PointMutationEngine(
        modeller.topology,
        system_generator,
        chain_id,
        proposal_metadata=metadata,
        max_point_mutants=max_point_mutants,
        always_change=True)

    current_system = system
    current_topology = modeller.topology
    current_positions = modeller.positions

    pm_top_engine._allowed_mutations = list()
    for k, proposed_amino in enumerate(aminos):
        pm_top_engine._allowed_mutations.append((str(k + 2), proposed_amino))
    pm_top_proposal = pm_top_engine.propose(current_system, current_topology)
    current_system = pm_top_proposal.new_system
    current_topology = pm_top_proposal.new_topology

    for chain in current_topology.chains():
        if chain.id == chain_id:
            # num_residues : int
            num_residues = len(chain._residues)
            break
    new_sequence = list()
    for residue in current_topology.residues():
        if residue.index == 0:
            continue
        if residue.index == (num_residues - 1):
            continue
        if residue.name in ['HID', 'HIE']:
            residue.name = 'HIS'
        new_sequence.append(residue.name)
    for i in range(len(aminos)):
        assert new_sequence[i] == aminos[i]

    pm_top_engine = topology_proposal.PointMutationEngine(
        current_topology,
        system_generator,
        chain_id,
        proposal_metadata=metadata,
        max_point_mutants=max_point_mutants)

    from perses.rjmc.topology_proposal import append_topology
    old_topology = app.Topology()
    append_topology(old_topology, current_topology)
    new_topology = app.Topology()
    append_topology(new_topology, current_topology)

    old_chemical_state_key = pm_top_engine.compute_state_key(old_topology)

    for chain in new_topology.chains():
        if chain.id == chain_id:
            # num_residues : int
            num_residues = len(chain._residues)
            break
    for proposed_location in range(1, num_residues - 1):
        print('Making mutations at residue %s' % proposed_location)
        original_residue_name = chain._residues[proposed_location].name
        matching_amino_found = 0
        for proposed_amino in aminos:
            pm_top_engine._allowed_mutations = [(str(proposed_location + 1),
                                                 proposed_amino)]
            new_topology = app.Topology()
            append_topology(new_topology, current_topology)
            old_system = current_system
            old_topology_natoms = sum([1 for atom in old_topology.atoms()])
            old_system_natoms = old_system.getNumParticles()
            if old_topology_natoms != old_system_natoms:
                msg = 'PolymerProposalEngine: old_topology has %d atoms, while old_system has %d atoms' % (
                    old_topology_natoms, old_system_natoms)
                raise Exception(msg)
            metadata = dict()

            for atom in new_topology.atoms():
                atom.old_index = atom.index

            index_to_new_residues, metadata = pm_top_engine._choose_mutant(
                new_topology, metadata)
            if len(index_to_new_residues) == 0:
                matching_amino_found += 1
                continue
            print('Mutating %s to %s' %
                  (original_residue_name, proposed_amino))

            residue_map = pm_top_engine._generate_residue_map(
                new_topology, index_to_new_residues)
            for res_pair in residue_map:
                residue = res_pair[0]
                name = res_pair[1]
                assert residue.index in index_to_new_residues.keys()
                assert index_to_new_residues[residue.index] == name
                assert residue.name + '-' + str(
                    residue.id) + '-' + name in metadata['mutations']

            new_topology, missing_atoms = pm_top_engine._delete_excess_atoms(
                new_topology, residue_map)
            new_topology = pm_top_engine._add_new_atoms(
                new_topology, missing_atoms, residue_map)
            for res_pair in residue_map:
                residue = res_pair[0]
                name = res_pair[1]
                assert residue.name == name

            atom_map = pm_top_engine._construct_atom_map(
                residue_map, old_topology, index_to_new_residues, new_topology)
            templates = pm_top_engine._ff.getMatchingTemplates(new_topology)
            assert [
                templates[index].name == residue.name
                for index, (residue, name) in enumerate(residue_map)
            ]

            new_chemical_state_key = pm_top_engine.compute_state_key(
                new_topology)
            new_system = pm_top_engine._system_generator.build_system(
                new_topology)
            pm_top_proposal = topology_proposal.TopologyProposal(
                new_topology=new_topology,
                new_system=new_system,
                old_topology=old_topology,
                old_system=old_system,
                old_chemical_state_key=old_chemical_state_key,
                new_chemical_state_key=new_chemical_state_key,
                logp_proposal=0.0,
                new_to_old_atom_map=atom_map)

        assert matching_amino_found == 1
Exemple #4
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def test_run_geometry_engine(index=0):
    """
    Run the geometry engine a few times to make sure that it actually runs
    without exceptions. Convert n-pentane to 2-methylpentane
    """
    import logging
    logging.basicConfig(level=logging.DEBUG)
    import copy
    molecule_name_1 = 'benzene'
    molecule_name_2 = 'biphenyl'
    #molecule_name_1 = 'imatinib'
    #molecule_name_2 = 'erlotinib'

    molecule1 = generate_initial_molecule(molecule_name_1)
    molecule2 = generate_initial_molecule(molecule_name_2)
    new_to_old_atom_mapping = align_molecules(molecule1, molecule2)

    sys1, pos1, top1 = oemol_to_openmm_system(molecule1, molecule_name_1)
    sys2, pos2, top2 = oemol_to_openmm_system(molecule2, molecule_name_2)

    import perses.rjmc.geometry as geometry
    import perses.rjmc.topology_proposal as topology_proposal
    from perses.tests.utils import compute_potential_components

    sm_top_proposal = topology_proposal.TopologyProposal(new_topology=top2, new_system=sys2, old_topology=top1, old_system=sys1,
                                                                      old_chemical_state_key='',new_chemical_state_key='', logp_proposal=0.0, new_to_old_atom_map=new_to_old_atom_mapping, metadata={'test':0.0})
    sm_top_proposal._beta = beta
    geometry_engine = geometry.FFAllAngleGeometryEngine(metadata={})
    # Turn on PDB file writing.
    geometry_engine.write_proposal_pdb = True
    geometry_engine.pdb_filename_prefix = 't13geometry-proposal'
    test_pdb_file = open("%s_to_%s_%d.pdb" % (molecule_name_1, molecule_name_2, index), 'w')

    valence_system = copy.deepcopy(sys2)
    valence_system.removeForce(3)
    valence_system.removeForce(3)
    integrator = openmm.VerletIntegrator(1*unit.femtoseconds)
    integrator_1 = openmm.VerletIntegrator(1*unit.femtoseconds)
    ctx_1 = openmm.Context(sys1, integrator_1)
    ctx_1.setPositions(pos1)
    ctx_1.setVelocitiesToTemperature(300*unit.kelvin)
    integrator_1.step(1000)
    pos1_new = ctx_1.getState(getPositions=True).getPositions(asNumpy=True)
    context = openmm.Context(sys2, integrator)
    context.setPositions(pos2)
    state = context.getState(getEnergy=True)
    print("Energy before proposal is: %s" % str(state.getPotentialEnergy()))
    openmm.LocalEnergyMinimizer.minimize(context)

    new_positions, logp_proposal = geometry_engine.propose(sm_top_proposal, pos1_new, beta)
    logp_reverse = geometry_engine.logp_reverse(sm_top_proposal, new_positions, pos1, beta)
    print(logp_reverse)

    app.PDBFile.writeFile(top2, new_positions, file=test_pdb_file)
    test_pdb_file.close()
    context.setPositions(new_positions)
    state2 = context.getState(getEnergy=True)
    print("Energy after proposal is: %s" %str(state2.getPotentialEnergy()))
    print(compute_potential_components(context))

    valence_integrator = openmm.VerletIntegrator(1*unit.femtoseconds)
    platform = openmm.Platform.getPlatformByName("Reference")
    valence_ctx = openmm.Context(valence_system, valence_integrator, platform)
    valence_ctx.setPositions(new_positions)
    vstate = valence_ctx.getState(getEnergy=True)
    print("Valence energy after proposal is %s " % str(vstate.getPotentialEnergy()))
    final_potential = state2.getPotentialEnergy()
    return final_potential / final_potential.unit