---
license: apache-2.0
library_name: pytorch
tags:
- biology
- protein
- protein-structure
- protein-structure-tokenizer
- structure-tokenizer
- dplm-2
- pytorch
- arxiv:2410.13782
- arxiv:2504.11454
datasets:
- airkingbd/pdb_swissprot
---

# DPLM-2 Structure Tokenizer

This repository contains the structure tokenizer used by DPLM-2, a multimodal
diffusion protein language model for joint protein sequence and structure
modeling. The tokenizer converts protein backbone/atom coordinates into
discrete structure tokens and can decode structure tokens back into protein
structures. DPLM-2 uses these tokens to support sequence-structure
co-generation, forward folding, inverse folding, and motif scaffolding.

For the official implementation, installation instructions, DPLM-2 generation
scripts, and evaluation utilities, see the
[bytedance/dplm](https://github.com/bytedance/dplm) repository.

## Model Details

- **Checkpoint:** `airkingbd/struct_tokenizer`
- **Files:** `config.yaml`, `dplm2_struct_tokenizer.ckpt`
- **Model class:** `byprot.models.structok.structok_lfq.VQModel`
- **Tokenizer type:** LFQ-based discrete protein structure tokenizer
- **Codebook size:** 8,192 structure tokens (`2^13`)
- **Codebook embedding dimension:** 13
- **Encoder:** GVP-based structure encoder
- **Decoder:** ESMFold-style structure decoder with decoder input dimension 128
- **License:** Apache-2.0
- **Paper:** [DPLM-2: A Multimodal Diffusion Protein Language Model](https://arxiv.org/abs/2410.13782)

## Quick Start

Install the official DPLM codebase and dependencies:

```bash
git clone --recursive https://github.com/bytedance/dplm.git
cd dplm

conda create -n dplm python=3.9 pip
conda activate dplm
bash scripts/install.sh
```

Load the released structure tokenizer:

```python
from byprot.models.utils import get_struct_tokenizer

struct_tokenizer = get_struct_tokenizer("airkingbd/struct_tokenizer")
struct_tokenizer = struct_tokenizer.cuda().eval()
```

The helper downloads this repository from Hugging Face, reads `config.yaml`,
constructs `VQModel`, and loads `dplm2_struct_tokenizer.ckpt`.

## Tokenize PDB Structures

The official repository provides `src/byprot/utils/protein/tokenize_pdb.py` for
converting PDB files into structure-token FASTA files:

```bash
python src/byprot/utils/protein/tokenize_pdb.py \
    --input_pdb_folder /path/to/input/pdbs \
    --output_dir /path/to/output/tokenized_protein
```

The script processes `*.pdb` files in the input folder and writes:

- `struct_seq.fasta`: tokenized structure sequences
- `aa_seq.fasta`: amino-acid sequences extracted from the same structures

The structure sequences can be used as DPLM-2 structure-conditioning inputs.
For example, pass the generated structure-token FASTA file to
`generate_dplm2.py --task inverse_folding --input_fasta_path ...`.


## Use with DPLM-2

DPLM-2 checkpoints load this tokenizer through their `struct_tokenizer` property.
For example:

```python
from byprot.models.dplm2 import MultimodalDiffusionProteinLanguageModel as DPLM2

dplm2 = DPLM2.from_pretrained("airkingbd/dplm2_650m").cuda().eval()
struct_tokenizer = dplm2.struct_tokenizer
```

The DPLM-2 configs point to this repository with:

```yaml
struct_tokenizer:
  exp_path: airkingbd/struct_tokenizer
```


## Citation

If you use this tokenizer, please cite the DPLM and DPLM-2 papers:

```bibtex
@inproceedings{wang2024dplm,
  title={Diffusion Language Models Are Versatile Protein Learners},
  author={Wang, Xinyou and Zheng, Zaixiang and Ye, Fei and Xue, Dongyu and Huang, Shujian and Gu, Quanquan},
  booktitle={International Conference on Machine Learning},
  year={2024}
}

@inproceedings{wang2025dplm2,
  title={DPLM-2: A Multimodal Diffusion Protein Language Model},
  author={Wang, Xinyou and Zheng, Zaixiang and Ye, Fei and Xue, Dongyu and Huang, Shujian and Gu, Quanquan},
  booktitle={International Conference on Learning Representations},
  year={2025}
}

@inproceedings{hsieh2025dplm2_1,
  title={Elucidating the Design Space of Multimodal Protein Language Models},
  author={Hsieh, Cheng-Yen and Wang, Xinyou and Zhang, Daiheng and Xue, Dongyu and Ye, Fei and Huang, Shujian and Zheng, Zaixiang and Gu, Quanquan},
  booktitle={International Conference on Machine Learning},
  year={2025}
}
```

## Acknowledgements

DPLM builds on and acknowledges prior work and resources including ByProt,
ESM, OpenFold-related structure modeling utilities, EigenFold, and MultiFlow.
See the official repository for complete acknowledgements and implementation
details.