AntiFold 预测适合抗体可变结构域结构的序列。该工具以 CSV 格式输出残差对数似然，并且可以直接将序列采样为 FASTA 格式。采样序列显示出与实验结构高度一致的结构。
AntiFold 基于 ESM-IF1 模型，并根据 SAbDab 和 OAS 解析和预测的抗体结构进行了微调。
要在不安装 AntiFold 的情况下尝试它，请参阅我们的 OPIG 网络服务器：https://opig.stats.ox.ac.uk/webapps/antifold/
conda create --name antifold python=3.10 -y && conda activate antifold
conda install -c conda-forge pytorch
git clone https://github.com/oxpig/AntiFold && cd AntiFold
pip install .仅 GPU：使用environment.yml 安装
conda create env -f environment.yml
python -m pip install .根据您的 CUDA 版本，您可能需要更改environment.yml 文件中的依赖项pytorch-cuda=12.1 。有关如何为您的系统正确安装 pytorch 的详细说明可以在此处找到
# Run AntiFold on single PDB/CIF file
# Nb: Assumes first chain heavy, second chain light
python antifold/main.py
--pdb_file data/pdbs/6y1l_imgt.pdb
# Antibody-antigen complex
python antifold/main.py
--pdb_file data/antibody_antigen/3hfm.pdb
--heavy_chain H
--light_chain L
--antigen_chain Y
# Nanobody or single-chain
python antifold/main.py
--pdb_file data/nanobody/8oi2_imgt.pdb
--nanobody_chain B
# Folder of PDB/CIFs
# Nb: Assumes first chain heavy, second light
python antifold/main.py
--pdb_dir data/pdbs
# Specify chains to run in a CSV file (e.g. antibody-antigen complex)
python antifold/main.py
--pdb_dir data/antibody_antigen
--pdbs_csv data/antibody_antigen.csv
# Sample sequences 10x (paired VH/VL only)
python antifold/main.py
--pdb_file data/pdbs/6y1l_imgt.pdb
--heavy_chain H
--light_chain L
--num_seq_per_target 10
--sampling_temp " 0.2 "
--regions " CDR1 CDR2 CDR3 "
# Run all chains with ESM-IF1 model weights
python antifold/main.py
--pdb_dir data/pdbs
--esm_if1_mode笔记本：notebook.ipynb
科拉布：
import antifold
import antifold . main
# Load model
model = antifold . main . load_model ()
# PDB directory
pdb_dir = "data/pdbs"
# Assumes first chain heavy, second chain light
pdbs_csv = antifold . main . generate_pdbs_csv ( pdb_dir , max_chains = 2 )
# Sample from PDBs
df_logits_list = antifold . main . get_pdbs_logits (
model = model ,
pdbs_csv_or_dataframe = pdbs_csv ,
pdb_dir = pdb_dir ,
)
# Output log probabilites
df_logits_list [ 0 ]所需参数：
Input PDBs should be antibody variable domain structures (IMGT positions 1-128).
If no chains are specified, the first two chains will be assumed to be heavy light.
If custom_chain_mode is set, all (10) chains will be run.
- Option 1: PDB file (--pdb_file). We recommend specifying heavy and light chain (--heavy_chain and --light_chain)
- Option 2: PDB folder (--pdb_dir) + CSV file specifying chains (--pdbs_csv)
- Option 3: PDB folder, infer 1st chain heavy, 2nd chain light
生成新序列的参数：
PDBs should be IMGT annotated for the sequence sampling regions to be valid.
- Number of sequences to generate (--num_seq_per_target)
- Region to mutate (--region) based on inverse folding probabilities. Select from list in IMGT_dict (e.g. 'CDRH1 CDRH2 CDRH3')
- Sampling temperature (--sampling_temp) controls generated sequence diversity, by scaling the inverse folding probabilities before sampling. Temperature = 1 means no change, while temperature ~ 0 only samples the most likely amino-acid at each position (acts as argmax).
可选参数：
- Multi-chain mode for including antigen or other chains (--custom_chain_mode)
- Extract latent representations of PDB within model (--extract_embeddings)
- Use ESM-IF1 instead of AntiFold model weights (--esm_if1_mode), enables custom_chain_mode
例如网络服务器输出，请参阅：https://opig.stats.ox.ac.uk/webapps/antifold/results/example_job/
带有残留对数概率的输出 CSV：残留概率：6y1l_imgt.csv
pdb_pos,pdb_chain,aa_orig,aa_pred,pdb_posins,perplexity,A,C,D,E,F,G,H,I,K,L,M,N,P,Q,R,S,T,V,W,Y
2,H,V,M,2,1.6488,-4.9963,-6.6117,-6.3181,-6.3243,-6.7570,-4.2518,-6.7514,-5.2540,-6.8067,-5.8619,-0.0904,-6.5493,-4.8639,-6.6316,-6.3084,-5.1900,-5.0988,-3.7295,-8.0480,-7.3236
3,H,Q,Q,3,1.3889,-10.5258,-12.8463,-8.4800,-4.7630,-12.9094,-11.0924,-5.6136,-10.9870,-3.1119,-8.1113,-9.4382,-6.2246,-13.3660,-0.0701,-4.9957,-10.0301,-6.8618,-7.5810,-13.6721,-11.4157
4,H,L,L,4,1.0021,-13.3581,-12.6206,-17.5484,-12.4801,-9.8792,-13.6382,-14.8609,-13.9344,-16.4080,-0.0002,-9.2727,-16.6532,-14.0476,-12.5943,-15.4559,-16.9103,-17.0809,-10.5670,-13.5334,-13.4324
...
输出带有采样序列的 FASTA 文件：6y1l_imgt.fasta
>6y1l_imgt , score=0.2934, global_score=0.2934, regions=['CDR1', 'CDR2', 'CDRH3'], model_name=AntiFold, seed=42
VQLQESGPGLVKPSETLSLTCAVSGYSISSGYYWGWIRQPPGKGLEWIGSIYHSGSTYYN
PSLKSRVTISVDTSKNQFSLKLSSVTAADTAVYYCAGLTQSSHNDANWGQGTLVTVSS/V
LTQPPSVSAAPGQKVTISCSGSSSNIGNNYVSWYQQLPGTAPKRLIYDNNKRPSGIPDRF
SGSKSGTSATLGITGLQTGDEADYYCGTWDSSLNPVFGGGTKLEIKR
> T=0.20, sample=1, score=0.3930, global_score=0.1869, seq_recovery=0.8983, mutations=12
VQLQESGPGLVKPSETLSLTCAVSGASITSSYYWGWIRQPPGKGLEWIGSIYYSGSTYYN
PSLKSRVTISVDTSKNQFSLKLSSVTAADTAVYYCAGLYGSPWSNPYWGQGTLVTVSS/V
LTQPPSVSAAPGQKVTISCSGSSSNIGNNYVSWYQQLPGTAPKRLIYDNNKRPSGIPDRF
SGSKSGTSATLGITGLQTGDEADYYCGTWDSSLNPVFGGGTKLEIKR
...
usage:
# Predict on example PDBs in folder
python antifold/main.py
--pdb_file data/antibody_antigen/3hfm.pdb
--heavy_chain H
--light_chain L
--antigen_chain Y # Optional
Predict inverse folding probabilities for antibody variable domain, and sample sequences with maintained fold.
PDB structures should be IMGT-numbered, paired heavy and light chain variable domains (positions 1-128).
For IMGT numbering PDBs use SAbDab or https://opig.stats.ox.ac.uk/webapps/sabdab-sabpred/sabpred/anarci/
options:
-h, --help show this help message and exit
--pdb_file PDB_FILE Input PDB file (for single PDB predictions)
--heavy_chain HEAVY_CHAIN
Ab heavy chain (for single PDB predictions)
--light_chain LIGHT_CHAIN
Ab light chain (for single PDB predictions)
--antigen_chain ANTIGEN_CHAIN
Antigen chain (optional)
--pdbs_csv PDBS_CSV Input CSV file with PDB names and H/L chains (multi-PDB predictions)
--pdb_dir PDB_DIR Directory with input PDB files (multi-PDB predictions)
--out_dir OUT_DIR Output directory
--regions REGIONS Space-separated regions to mutate. Default ' CDR1 CDR2 CDR3H '
--num_seq_per_target NUM_SEQ_PER_TARGET
Number of sequences to sample from each antibody PDB (default 0)
--sampling_temp SAMPLING_TEMP
A string of temperatures e.g. ' 0.20 0.25 0.50 ' (default 0.20). Sampling temperature for amino acids. Suggested values 0.10, 0.15, 0.20, 0.25, 0.30. Higher values will lead to more diversity.
--limit_variation Limit variation to as many mutations as expected from temperature sampling
--extract_embeddings Extract per-residue embeddings from AntiFold / ESM-IF1
--custom_chain_mode Run all specified chains (for antibody-antigen complexes or any combination of chains)
--exclude_heavy Exclude heavy chain from sampling
--exclude_light Exclude light chain from sampling
--batch_size BATCH_SIZE
Batch-size to use
--num_threads NUM_THREADS
Number of CPU threads to use for parallel processing (0 = all available)
--seed SEED Seed for reproducibility
--model_path MODEL_PATH
Alternative model weights (default models/model.pt). See --use_esm_if1_weights flag to use ESM-IF1 weights instead of AntiFold
--esm_if1_mode Use ESM-IF1 weights instead of AntiFold
--verbose VERBOSE Verbose printing用于指定 IMGT 编号的 PDB 中要变异的区域
IMGT_dict = {
"all" : range ( 1 , 128 + 1 ),
"allH" : range ( 1 , 128 + 1 ),
"allL" : range ( 1 , 128 + 1 ),
"FWH" : list ( range ( 1 , 26 + 1 )) + list ( range ( 40 , 55 + 1 )) + list ( range ( 66 , 104 + 1 )),
"FWL" : list ( range ( 1 , 26 + 1 )) + list ( range ( 40 , 55 + 1 )) + list ( range ( 66 , 104 + 1 )),
"CDRH" : list ( range ( 27 , 39 )) + list ( range ( 56 , 65 + 1 )) + list ( range ( 105 , 117 + 1 )),
"CDRL" : list ( range ( 27 , 39 )) + list ( range ( 56 , 65 + 1 )) + list ( range ( 105 , 117 + 1 )),
"FW1" : range ( 1 , 26 + 1 ),
"FWH1" : range ( 1 , 26 + 1 ),
"FWL1" : range ( 1 , 26 + 1 ),
"CDR1" : range ( 27 , 39 ),
"CDRH1" : range ( 27 , 39 ),
"CDRL1" : range ( 27 , 39 ),
"FW2" : range ( 40 , 55 + 1 ),
"FWH2" : range ( 40 , 55 + 1 ),
"FWL2" : range ( 40 , 55 + 1 ),
"CDR2" : range ( 56 , 65 + 1 ),
"CDRH2" : range ( 56 , 65 + 1 ),
"CDRL2" : range ( 56 , 65 + 1 ),
"FW3" : range ( 66 , 104 + 1 ),
"FWH3" : range ( 66 , 104 + 1 ),
"FWL3" : range ( 66 , 104 + 1 ),
"CDR3" : range ( 105 , 117 + 1 ),
"CDRH3" : range ( 105 , 117 + 1 ),
"CDRL3" : range ( 105 , 117 + 1 ),
"FW4" : range ( 118 , 128 + 1 ),
"FWH4" : range ( 118 , 128 + 1 ),
"FWL4" : range ( 118 , 128 + 1 ),
}该包中的代码和数据基于以下论文AntiFold。如果您使用它，请引用：
@misc{antifold,
title={AntiFold: Improved antibody structure-based design using inverse folding},
author={Magnus Haraldson Høie and Alissa Hummer and Tobias H. Olsen and Broncio Aguilar-Sanjuan and Morten Nielsen and Charlotte M. Deane},
year={2024},
eprint={2405.03370},
archivePrefix={arXiv},
primaryClass={q-bio.BM}
}
