--- a +++ b/process_crossdock.py @@ -0,0 +1,443 @@ +from pathlib import Path +from time import time +import argparse +import shutil +import random + +import matplotlib.pyplot as plt +import seaborn as sns + +from tqdm import tqdm +import numpy as np + +from Bio.PDB import PDBParser +from Bio.PDB.Polypeptide import three_to_one, is_aa +from rdkit import Chem +from scipy.ndimage import gaussian_filter + +import torch + +from analysis.molecule_builder import build_molecule +from analysis.metrics import rdmol_to_smiles +import constants +from constants import covalent_radii, dataset_params + + +def process_ligand_and_pocket(pdbfile, sdffile, + atom_dict, dist_cutoff, ca_only): + pdb_struct = PDBParser(QUIET=True).get_structure('', pdbfile) + + try: + ligand = Chem.SDMolSupplier(str(sdffile))[0] + except: + raise Exception(f'cannot read sdf mol ({sdffile})') + + # remove H atoms if not in atom_dict, other atom types that aren't allowed + # should stay so that the entire ligand can be removed from the dataset + lig_atoms = [a.GetSymbol() for a in ligand.GetAtoms() + if (a.GetSymbol().capitalize() in atom_dict or a.element != 'H')] + lig_coords = np.array([list(ligand.GetConformer(0).GetAtomPosition(idx)) + for idx in range(ligand.GetNumAtoms())]) + + try: + lig_one_hot = np.stack([ + np.eye(1, len(atom_dict), atom_dict[a.capitalize()]).squeeze() + for a in lig_atoms + ]) + except KeyError as e: + raise KeyError( + f'{e} not in atom dict ({sdffile})') + + # Find interacting pocket residues based on distance cutoff + pocket_residues = [] + for residue in pdb_struct[0].get_residues(): + res_coords = np.array([a.get_coord() for a in residue.get_atoms()]) + if is_aa(residue.get_resname(), standard=True) and \ + (((res_coords[:, None, :] - lig_coords[None, :, :]) ** 2).sum( + -1) ** 0.5).min() < dist_cutoff: + pocket_residues.append(residue) + + pocket_ids = [f'{res.parent.id}:{res.id[1]}' for res in pocket_residues] + ligand_data = { + 'lig_coords': lig_coords, + 'lig_one_hot': lig_one_hot, + } + if ca_only: + try: + pocket_one_hot = [] + full_coords = [] + for res in pocket_residues: + for atom in res.get_atoms(): + if atom.name == 'CA': + pocket_one_hot.append(np.eye(1, len(amino_acid_dict), + amino_acid_dict[three_to_one(res.get_resname())]).squeeze()) + full_coords.append(atom.coord) + pocket_one_hot = np.stack(pocket_one_hot) + full_coords = np.stack(full_coords) + except KeyError as e: + raise KeyError( + f'{e} not in amino acid dict ({pdbfile}, {sdffile})') + pocket_data = { + 'pocket_coords': full_coords, + 'pocket_one_hot': pocket_one_hot, + 'pocket_ids': pocket_ids + } + else: + full_atoms = np.concatenate( + [np.array([atom.element for atom in res.get_atoms()]) + for res in pocket_residues], axis=0) + full_coords = np.concatenate( + [np.array([atom.coord for atom in res.get_atoms()]) + for res in pocket_residues], axis=0) + try: + pocket_one_hot = [] + for a in full_atoms: + if a in amino_acid_dict: + atom = np.eye(1, len(amino_acid_dict), + amino_acid_dict[a.capitalize()]).squeeze() + elif a != 'H': + atom = np.eye(1, len(amino_acid_dict), + len(amino_acid_dict)).squeeze() + pocket_one_hot.append(atom) + pocket_one_hot = np.stack(pocket_one_hot) + except KeyError as e: + raise KeyError( + f'{e} not in atom dict ({pdbfile})') + pocket_data = { + 'pocket_coords': full_coords, + 'pocket_one_hot': pocket_one_hot, + 'pocket_ids': pocket_ids + } + return ligand_data, pocket_data + + +def compute_smiles(positions, one_hot, mask): + print("Computing SMILES ...") + + atom_types = np.argmax(one_hot, axis=-1) + + sections = np.where(np.diff(mask))[0] + 1 + positions = [torch.from_numpy(x) for x in np.split(positions, sections)] + atom_types = [torch.from_numpy(x) for x in np.split(atom_types, sections)] + + mols_smiles = [] + + pbar = tqdm(enumerate(zip(positions, atom_types)), + total=len(np.unique(mask))) + for i, (pos, atom_type) in pbar: + mol = build_molecule(pos, atom_type, dataset_info) + + # BasicMolecularMetrics() computes SMILES after sanitization + try: + Chem.SanitizeMol(mol) + except ValueError: + continue + + mol = rdmol_to_smiles(mol) + if mol is not None: + mols_smiles.append(mol) + pbar.set_description(f'{len(mols_smiles)}/{i + 1} successful') + + return mols_smiles + + +def get_n_nodes(lig_mask, pocket_mask, smooth_sigma=None): + # Joint distribution of ligand's and pocket's number of nodes + idx_lig, n_nodes_lig = np.unique(lig_mask, return_counts=True) + idx_pocket, n_nodes_pocket = np.unique(pocket_mask, return_counts=True) + assert np.all(idx_lig == idx_pocket) + + joint_histogram = np.zeros((np.max(n_nodes_lig) + 1, + np.max(n_nodes_pocket) + 1)) + + for nlig, npocket in zip(n_nodes_lig, n_nodes_pocket): + joint_histogram[nlig, npocket] += 1 + + print(f'Original histogram: {np.count_nonzero(joint_histogram)}/' + f'{joint_histogram.shape[0] * joint_histogram.shape[1]} bins filled') + + # Smooth the histogram + if smooth_sigma is not None: + filtered_histogram = gaussian_filter( + joint_histogram, sigma=smooth_sigma, order=0, mode='constant', + cval=0.0, truncate=4.0) + + print(f'Smoothed histogram: {np.count_nonzero(filtered_histogram)}/' + f'{filtered_histogram.shape[0] * filtered_histogram.shape[1]} bins filled') + + joint_histogram = filtered_histogram + + return joint_histogram + + +def get_bond_length_arrays(atom_mapping): + bond_arrays = [] + for i in range(3): + bond_dict = getattr(constants, f'bonds{i + 1}') + bond_array = np.zeros((len(atom_mapping), len(atom_mapping))) + for a1 in atom_mapping.keys(): + for a2 in atom_mapping.keys(): + if a1 in bond_dict and a2 in bond_dict[a1]: + bond_len = bond_dict[a1][a2] + else: + bond_len = 0 + bond_array[atom_mapping[a1], atom_mapping[a2]] = bond_len + + assert np.all(bond_array == bond_array.T) + bond_arrays.append(bond_array) + + return bond_arrays + + +def get_lennard_jones_rm(atom_mapping): + # Bond radii for the Lennard-Jones potential + LJ_rm = np.zeros((len(atom_mapping), len(atom_mapping))) + + for a1 in atom_mapping.keys(): + for a2 in atom_mapping.keys(): + all_bond_lengths = [] + for btype in ['bonds1', 'bonds2', 'bonds3']: + bond_dict = getattr(constants, btype) + if a1 in bond_dict and a2 in bond_dict[a1]: + all_bond_lengths.append(bond_dict[a1][a2]) + + if len(all_bond_lengths) > 0: + # take the shortest possible bond length because slightly larger + # values aren't penalized as much + bond_len = min(all_bond_lengths) + else: + if a1 == 'others' or a2 == 'others': + bond_len = 0 + else: + # Replace missing values with sum of average covalent radii + bond_len = covalent_radii[a1] + covalent_radii[a2] + + LJ_rm[atom_mapping[a1], atom_mapping[a2]] = bond_len + + assert np.all(LJ_rm == LJ_rm.T) + return LJ_rm + + +def get_type_histograms(lig_one_hot, pocket_one_hot, atom_encoder, aa_encoder): + atom_decoder = list(atom_encoder.keys()) + atom_counts = {k: 0 for k in atom_encoder.keys()} + for a in [atom_decoder[x] for x in lig_one_hot.argmax(1)]: + atom_counts[a] += 1 + + aa_decoder = list(aa_encoder.keys()) + aa_counts = {k: 0 for k in aa_encoder.keys()} + for r in [aa_decoder[x] for x in pocket_one_hot.argmax(1)]: + aa_counts[r] += 1 + + return atom_counts, aa_counts + + +def saveall(filename, pdb_and_mol_ids, lig_coords, lig_one_hot, lig_mask, + pocket_coords, pocket_one_hot, pocket_mask): + np.savez(filename, + names=pdb_and_mol_ids, + lig_coords=lig_coords, + lig_one_hot=lig_one_hot, + lig_mask=lig_mask, + pocket_coords=pocket_coords, + pocket_one_hot=pocket_one_hot, + pocket_mask=pocket_mask + ) + return True + + +if __name__ == '__main__': + parser = argparse.ArgumentParser() + parser.add_argument('basedir', type=Path) + parser.add_argument('--outdir', type=Path, default=None) + parser.add_argument('--no_H', action='store_true') + parser.add_argument('--ca_only', action='store_true') + parser.add_argument('--dist_cutoff', type=float, default=8.0) + parser.add_argument('--random_seed', type=int, default=42) + args = parser.parse_args() + + datadir = args.basedir / 'crossdocked_pocket10/' + + if args.ca_only: + dataset_info = dataset_params['crossdock'] + else: + dataset_info = dataset_params['crossdock_full'] + amino_acid_dict = dataset_info['aa_encoder'] + atom_dict = dataset_info['atom_encoder'] + atom_decoder = dataset_info['atom_decoder'] + + # Make output directory + if args.outdir is None: + suffix = '_crossdock' if 'H' in atom_dict else '_crossdock_noH' + suffix += '_ca_only_temp' if args.ca_only else '_full_temp' + processed_dir = Path(args.basedir, f'processed{suffix}') + else: + processed_dir = args.outdir + + processed_dir.mkdir(exist_ok=True, parents=True) + + # Read data split + split_path = Path(args.basedir, 'split_by_name.pt') + data_split = torch.load(split_path) + + # There is no validation set, copy 300 training examples (the validation set + # is not very important in this application) + # Note: before we had a data leak but it should not matter too much as most + # metrics monitored during training are independent of the pockets + data_split['val'] = random.sample(data_split['train'], 300) + + n_train_before = len(data_split['train']) + n_val_before = len(data_split['val']) + n_test_before = len(data_split['test']) + + failed_save = [] + + n_samples_after = {} + for split in data_split.keys(): + lig_coords = [] + lig_one_hot = [] + lig_mask = [] + pocket_coords = [] + pocket_one_hot = [] + pocket_mask = [] + pdb_and_mol_ids = [] + count_protein = [] + count_ligand = [] + count_total = [] + count = 0 + + pdb_sdf_dir = processed_dir / split + pdb_sdf_dir.mkdir(exist_ok=True) + + tic = time() + num_failed = 0 + pbar = tqdm(data_split[split]) + pbar.set_description(f'#failed: {num_failed}') + for pocket_fn, ligand_fn in pbar: + + sdffile = datadir / f'{ligand_fn}' + pdbfile = datadir / f'{pocket_fn}' + + try: + struct_copy = PDBParser(QUIET=True).get_structure('', pdbfile) + except: + num_failed += 1 + failed_save.append((pocket_fn, ligand_fn)) + print(failed_save[-1]) + pbar.set_description(f'#failed: {num_failed}') + continue + + try: + ligand_data, pocket_data = process_ligand_and_pocket( + pdbfile, sdffile, + atom_dict=atom_dict, dist_cutoff=args.dist_cutoff, + ca_only=args.ca_only) + except (KeyError, AssertionError, FileNotFoundError, IndexError, + ValueError) as e: + print(type(e).__name__, e, pocket_fn, ligand_fn) + num_failed += 1 + pbar.set_description(f'#failed: {num_failed}') + continue + + pdb_and_mol_ids.append(f"{pocket_fn}_{ligand_fn}") + lig_coords.append(ligand_data['lig_coords']) + lig_one_hot.append(ligand_data['lig_one_hot']) + lig_mask.append(count * np.ones(len(ligand_data['lig_coords']))) + pocket_coords.append(pocket_data['pocket_coords']) + pocket_one_hot.append(pocket_data['pocket_one_hot']) + pocket_mask.append( + count * np.ones(len(pocket_data['pocket_coords']))) + count_protein.append(pocket_data['pocket_coords'].shape[0]) + count_ligand.append(ligand_data['lig_coords'].shape[0]) + count_total.append(pocket_data['pocket_coords'].shape[0] + + ligand_data['lig_coords'].shape[0]) + count += 1 + + if split in {'val', 'test'}: + # Copy PDB file + new_rec_name = Path(pdbfile).stem.replace('_', '-') + pdb_file_out = Path(pdb_sdf_dir, f"{new_rec_name}.pdb") + shutil.copy(pdbfile, pdb_file_out) + + # Copy SDF file + new_lig_name = new_rec_name + '_' + Path(sdffile).stem.replace('_', '-') + sdf_file_out = Path(pdb_sdf_dir, f'{new_lig_name}.sdf') + shutil.copy(sdffile, sdf_file_out) + + # specify pocket residues + with open(Path(pdb_sdf_dir, f'{new_lig_name}.txt'), 'w') as f: + f.write(' '.join(pocket_data['pocket_ids'])) + + lig_coords = np.concatenate(lig_coords, axis=0) + lig_one_hot = np.concatenate(lig_one_hot, axis=0) + lig_mask = np.concatenate(lig_mask, axis=0) + pocket_coords = np.concatenate(pocket_coords, axis=0) + pocket_one_hot = np.concatenate(pocket_one_hot, axis=0) + pocket_mask = np.concatenate(pocket_mask, axis=0) + + saveall(processed_dir / f'{split}.npz', pdb_and_mol_ids, lig_coords, + lig_one_hot, lig_mask, pocket_coords, + pocket_one_hot, pocket_mask) + + n_samples_after[split] = len(pdb_and_mol_ids) + print(f"Processing {split} set took {(time() - tic) / 60.0:.2f} minutes") + + # -------------------------------------------------------------------------- + # Compute statistics & additional information + # -------------------------------------------------------------------------- + with np.load(processed_dir / 'train.npz', allow_pickle=True) as data: + lig_mask = data['lig_mask'] + pocket_mask = data['pocket_mask'] + lig_coords = data['lig_coords'] + lig_one_hot = data['lig_one_hot'] + pocket_one_hot = data['pocket_one_hot'] + + # Compute SMILES for all training examples + train_smiles = compute_smiles(lig_coords, lig_one_hot, lig_mask) + np.save(processed_dir / 'train_smiles.npy', train_smiles) + + # Joint histogram of number of ligand and pocket nodes + n_nodes = get_n_nodes(lig_mask, pocket_mask, smooth_sigma=1.0) + np.save(Path(processed_dir, 'size_distribution.npy'), n_nodes) + + # Convert bond length dictionaries to arrays for batch processing + bonds1, bonds2, bonds3 = get_bond_length_arrays(atom_dict) + + # Get bond length definitions for Lennard-Jones potential + rm_LJ = get_lennard_jones_rm(atom_dict) + + # Get histograms of ligand and pocket node types + atom_hist, aa_hist = get_type_histograms(lig_one_hot, pocket_one_hot, + atom_dict, amino_acid_dict) + + # Create summary string + summary_string = '# SUMMARY\n\n' + summary_string += '# Before processing\n' + summary_string += f'num_samples train: {n_train_before}\n' + summary_string += f'num_samples val: {n_val_before}\n' + summary_string += f'num_samples test: {n_test_before}\n\n' + summary_string += '# After processing\n' + summary_string += f"num_samples train: {n_samples_after['train']}\n" + summary_string += f"num_samples val: {n_samples_after['val']}\n" + summary_string += f"num_samples test: {n_samples_after['test']}\n\n" + summary_string += '# Info\n' + summary_string += f"'atom_encoder': {atom_dict}\n" + summary_string += f"'atom_decoder': {list(atom_dict.keys())}\n" + summary_string += f"'aa_encoder': {amino_acid_dict}\n" + summary_string += f"'aa_decoder': {list(amino_acid_dict.keys())}\n" + summary_string += f"'bonds1': {bonds1.tolist()}\n" + summary_string += f"'bonds2': {bonds2.tolist()}\n" + summary_string += f"'bonds3': {bonds3.tolist()}\n" + summary_string += f"'lennard_jones_rm': {rm_LJ.tolist()}\n" + summary_string += f"'atom_hist': {atom_hist}\n" + summary_string += f"'aa_hist': {aa_hist}\n" + summary_string += f"'n_nodes': {n_nodes.tolist()}\n" + + # Write summary to text file + with open(processed_dir / 'summary.txt', 'w') as f: + f.write(summary_string) + + # Print summary + print(summary_string) + + print(failed_save)