Example #1
0
def test_sanitizeSMILES():
    """
    Test SMILES sanitization.
    """
    from perses.utils.smallmolecules import sanitizeSMILES
    smiles_list = [
        'CC', 'CCC', '[H][C@]1(NC[C@@H](CC1CO[C@H]2CC[C@@H](CC2)O)N)[H]'
    ]

    sanitized_smiles_list = sanitizeSMILES(smiles_list, mode='drop')
    if len(sanitized_smiles_list) != 2:
        raise Exception(
            "Molecules with undefined stereochemistry are not being properly dropped (size=%d)."
            % len(sanitized_smiles_list))

    sanitized_smiles_list = sanitizeSMILES(smiles_list, mode='expand')
    if len(sanitized_smiles_list) != 4:
        raise Exception(
            "Molecules with undefined stereochemistry are not being properly expanded (size=%d)."
            % len(sanitized_smiles_list))

    # Check that all molecules can be round-tripped.
    from openeye.oechem import OEGraphMol, OESmilesToMol, OECreateIsoSmiString
    for smiles in sanitized_smiles_list:
        molecule = OEGraphMol()
        OESmilesToMol(molecule, smiles)
        isosmiles = OECreateIsoSmiString(molecule)
        if (smiles != isosmiles):
            raise Exception(
                "Molecule '%s' was not properly round-tripped (result was '%s')"
                % (smiles, isosmiles))
Example #2
0
def createSystemFromSMILES(smiles,title='MOL', **system_generator_kwargs):
    """
    Create an openmm system from a smiles string

    Parameters
    ----------
    smiles : str
        smiles string of molecule

    Returns
    -------
    molecule : openeye.oechem.OEMol
        OEMol molecule
    system : openmm.System object
        OpenMM system
    positions : [n,3] np.array of floats
        Positions
    topology : openmm.app.Topology object
        Topology
    """
    # clean up smiles string
    from perses.utils.smallmolecules import sanitizeSMILES
    smiles = sanitizeSMILES([smiles])
    smiles = smiles[0]

    # Create OEMol
    molecule = smiles_to_oemol(smiles, title=title)
    system_generator = system_generator_wrapper([molecule], **system_generator_kwargs)

    # generate openmm system, positions and topology
    system, positions, topology = OEMol_to_omm_ff(molecule, system_generator)

    return (molecule, system, positions, topology)
Example #3
0
    def __init__(self, **kwargs):
        super(Selectivity, self).__init__(**kwargs)

        solvents = ['explicit'] # DEBUG
        components = ['src-imatinib', 'abl-imatinib'] # TODO: Add 'ATP:kinase' complex to enable resistance design
        padding = 9.0*unit.angstrom
        explicit_solvent_model = 'tip3p'
        setup_path = 'data/abl-src'
        thermodynamic_states = dict()
        temperature = 300*unit.kelvin
        pressure = 1.0*unit.atmospheres
        geometry_engine = geometry.FFAllAngleGeometryEngine()


        # Construct list of all environments
        environments = list()
        for solvent in solvents:
            for component in components:
                environment = solvent + '-' + component
                environments.append(environment)

        # Read SMILES from CSV file of clinical kinase inhibitors.
        from pkg_resources import resource_filename
        smiles_filename = resource_filename('perses', 'data/clinical-kinase-inhibitors.csv')
        import csv
        molecules = list()
        with open(smiles_filename, 'r') as csvfile:
            csvreader = csv.reader(csvfile, delimiter=',', quotechar='"')
            for row in csvreader:
                name = row[0]
                smiles = row[1]
                molecules.append(smiles)
        # Add current molecule
        molecules.append('Cc1ccc(cc1Nc2nccc(n2)c3cccnc3)NC(=O)c4ccc(cc4)C[NH+]5CCN(CC5)C')
        self.molecules = molecules

        # Expand molecules without explicit stereochemistry and make canonical isomeric SMILES.
        molecules = sanitizeSMILES(self.molecules)

        # Create a system generator for desired forcefields
        from perses.rjmc.topology_proposal import SystemGenerator
        from pkg_resources import resource_filename
        gaff_xml_filename = resource_filename('perses', 'data/gaff.xml')
        system_generators = dict()
        system_generators['explicit'] = SystemGenerator([gaff_xml_filename, 'amber99sbildn.xml', 'tip3p.xml'],
            forcefield_kwargs={'nonbondedCutoff' : 9.0 * unit.angstrom, 'implicitSolvent' : None, 'constraints' : None },periodic_forcefield_kwargs = {'nonbondedMethod': app.CutoffPeriodic})
            use_antechamber=True)
Example #4
0
    def __init__(self, **kwargs):
        super(Selectivity, self).__init__(**kwargs)

        solvents = ['explicit'] # DEBUG
        components = ['src-imatinib', 'abl-imatinib'] # TODO: Add 'ATP:kinase' complex to enable resistance design
        padding = 9.0*unit.angstrom
        explicit_solvent_model = 'tip3p'
        setup_path = 'data/abl-src'
        thermodynamic_states = dict()
        temperature = 300*unit.kelvin
        pressure = 1.0*unit.atmospheres
        geometry_engine = geometry.FFAllAngleGeometryEngine()


        # Construct list of all environments
        environments = list()
        for solvent in solvents:
            for component in components:
                environment = solvent + '-' + component
                environments.append(environment)

        # Read SMILES from CSV file of clinical kinase inhibitors.
        from pkg_resources import resource_filename
        smiles_filename = resource_filename('perses', 'data/clinical-kinase-inhibitors.csv')
        import csv
        molecules = list()
        with open(smiles_filename, 'r') as csvfile:
            csvreader = csv.reader(csvfile, delimiter=',', quotechar='"')
            for row in csvreader:
                name = row[0]
                smiles = row[1]
                molecules.append(smiles)
        # Add current molecule
        molecules.append('Cc1ccc(cc1Nc2nccc(n2)c3cccnc3)NC(=O)c4ccc(cc4)C[NH+]5CCN(CC5)C')
        self.molecules = molecules

        # Expand molecules without explicit stereochemistry and make canonical isomeric SMILES.
        molecules = sanitizeSMILES(self.molecules)

        # Create a system generator for desired forcefields
        from perses.rjmc.topology_proposal import SystemGenerator
        from pkg_resources import resource_filename
        gaff_xml_filename = resource_filename('perses', 'data/gaff.xml')
        system_generators = dict()
        system_generators['explicit'] = SystemGenerator([gaff_xml_filename, 'amber99sbildn.xml', 'tip3p.xml'],
            forcefield_kwargs={ 'nonbondedMethod' : app.CutoffPeriodic, 'nonbondedCutoff' : 9.0 * unit.angstrom, 'implicitSolvent' : None, 'constraints' : None },
            use_antechamber=True)
# NOTE implicit solvent not supported by this SystemGenerator
#        system_generators['implicit'] = SystemGenerator([gaff_xml_filename, 'amber99sbildn.xml', 'amber99_obc.xml'],
#            forcefield_kwargs={ 'nonbondedMethod' : app.NoCutoff, 'implicitSolvent' : app.OBC2, 'constraints' : None },
#            use_antechamber=True)
        system_generators['vacuum'] = SystemGenerator([gaff_xml_filename, 'amber99sbildn.xml'],
            forcefield_kwargs={ 'nonbondedMethod' : app.NoCutoff, 'implicitSolvent' : None, 'constraints' : None },
            use_antechamber=True)
        # Copy system generators for all environments
        for solvent in solvents:
            for component in components:
                environment = solvent + '-' + component
                system_generators[environment] = system_generators[solvent]

        # Load topologies and positions for all components
        from simtk.openmm.app import PDBFile, Modeller
        topologies = dict()
        positions = dict()
        for component in components:
            pdb_filename = resource_filename('perses', os.path.join(setup_path, '%s.pdb' % component))
            print(pdb_filename)
            pdbfile = PDBFile(pdb_filename)
            topologies[component] = pdbfile.topology
            positions[component] = pdbfile.positions

        # Construct positions and topologies for all solvent environments
        for solvent in solvents:
            for component in components:
                environment = solvent + '-' + component
                if solvent == 'explicit':
                    # Create MODELLER object.
                    modeller = app.Modeller(topologies[component], positions[component])
                    modeller.addSolvent(system_generators[solvent].getForceField(), model='tip3p', padding=9.0*unit.angstrom)
                    topologies[environment] = modeller.getTopology()
                    positions[environment] = modeller.getPositions()
                else:
                    environment = solvent + '-' + component
                    topologies[environment] = topologies[component]
                    positions[environment] = positions[component]

        # Set up the proposal engines.
        from perses.rjmc.topology_proposal import SmallMoleculeSetProposalEngine
        proposal_metadata = { }
        proposal_engines = dict()
        for environment in environments:
            storage = None
            if self.storage:
                storage = NetCDFStorageView(self.storage, envname=environment)
            proposal_engines[environment] = SmallMoleculeSetProposalEngine(molecules, system_generators[environment], residue_name='MOL', storage=storage)

        # Generate systems
        systems = dict()
        for environment in environments:
            systems[environment] = system_generators[environment].build_system(topologies[environment])

        # Define thermodynamic state of interest.
        from perses.samplers.thermodynamics import ThermodynamicState
        thermodynamic_states = dict()
        temperature = 300*unit.kelvin
        pressure = 1.0*unit.atmospheres
        for component in components:
            for solvent in solvents:
                environment = solvent + '-' + component
                if solvent == 'explicit':
                    thermodynamic_states[environment] = ThermodynamicState(system=systems[environment], temperature=temperature, pressure=pressure)
                else:
                    thermodynamic_states[environment] = ThermodynamicState(system=systems[environment], temperature=temperature)

        # Create SAMS samplers
        from perses.samplers.samplers import SamplerState, MCMCSampler, ExpandedEnsembleSampler, SAMSSampler
        mcmc_samplers = dict()
        exen_samplers = dict()
        sams_samplers = dict()
        for solvent in solvents:
            for component in components:
                environment = solvent + '-' + component
                chemical_state_key = proposal_engines[environment].compute_state_key(topologies[environment])

                storage = None
                if self.storage:
                    storage = NetCDFStorageView(self.storage, envname=environment)

                if solvent == 'explicit':
                    thermodynamic_state = ThermodynamicState(system=systems[environment], temperature=temperature, pressure=pressure)
                    sampler_state = SamplerState(system=systems[environment], positions=positions[environment], box_vectors=systems[environment].getDefaultPeriodicBoxVectors())
                else:
                    thermodynamic_state = ThermodynamicState(system=systems[environment], temperature=temperature)
                    sampler_state = SamplerState(system=systems[environment], positions=positions[environment])

                mcmc_samplers[environment] = MCMCSampler(thermodynamic_state, sampler_state, storage=storage)
                mcmc_samplers[environment].nsteps = 5 # reduce number of steps for testing
                mcmc_samplers[environment].verbose = True
                exen_samplers[environment] = ExpandedEnsembleSampler(mcmc_samplers[environment], topologies[environment], chemical_state_key, proposal_engines[environment], options={'nsteps':10}, geometry_engine=geometry_engine, storage=storage)
                exen_samplers[environment].verbose = True
                sams_samplers[environment] = SAMSSampler(exen_samplers[environment], storage=storage)
                sams_samplers[environment].verbose = True
                thermodynamic_states[environment] = thermodynamic_state

        # Create test MultiTargetDesign sampler.

        from perses.samplers.samplers import MultiTargetDesign
        target_samplers = {sams_samplers['explicit-src-imatinib']: 1.0, sams_samplers['explicit-abl-imatinib']: -1.0}
        designer = MultiTargetDesign(target_samplers, storage=self.storage)
        designer.verbose = True

        # Store things.
        self.molecules = molecules
        self.environments = environments
        self.topologies = topologies
        self.positions = positions
        self.system_generators = system_generators
        self.systems = systems
        self.proposal_engines = proposal_engines
        self.thermodynamic_states = thermodynamic_states
        self.mcmc_samplers = mcmc_samplers
        self.exen_samplers = exen_samplers
        self.sams_samplers = sams_samplers
        self.designer = designer

        # This system must currently be minimized.
        minimize(self)