toxolib 0.1.0

A tool for metagenomic taxonomic profiling and abundance matrix generation

toxolib

A Python package for metagenomic taxonomic profiling and abundance matrix generation.

Installation

Using pip

pip install toxolib

Install directly from GitHub

pip install git+https://github.com/dhruvac29/toxolib.git

Using conda

We recommend using conda to install all dependencies. An environment file is included in the package:

# Clone the repository
git clone https://github.com/dhruvac29/toxolib.git
cd toxolib

# Create and activate the conda environment
conda env create -f environment.yml
conda activate taxonomy_env

# Install the package
pip install -e .

Requirements

This package requires the following external tools to be installed and available in your PATH:

• Kraken2
• Bracken
• Krona (for visualization)
• fastp (for preprocessing)
• bowtie2 (for host removal)
• samtools

All these dependencies are included in the conda environment file.

You'll also need to set the environment variable KRAKEN2_DB_DIR to the path of your Kraken2 database:

export KRAKEN2_DB_DIR=/path/to/kraken2/database

Usage

Local Usage

Generate abundance matrix from raw data

toxolib abundance -r raw_data_1.fastq.gz raw_data_2.fastq.gz -o output_directory

This will:

1. Run Kraken2 on the raw data
2. Run Bracken on the Kraken2 results
3. Generate an abundance matrix from the Bracken results

Create abundance matrix from existing Bracken files

toxolib matrix -i sample1_species.bracken sample2_species.bracken -o abundance_matrix.csv

HPC Usage

Toxolib can run the analysis pipeline on an HPC cluster using SLURM for job scheduling.

1. Set up HPC connection

toxolib hpc-setup --hostname your-hpc-server.edu --username your-username --key-file ~/.ssh/id_rsa

This will save your HPC connection details to ~/.toxolib/hpc_config.yaml.

2. Run the pipeline on HPC

toxolib hpc -r raw_data_1.fastq.gz raw_data_2.fastq.gz -o /path/on/hpc/output_dir \
    --kraken-db /path/on/hpc/kraken2_db \
    --corn-db /path/on/hpc/corn_db

This will:

1. Upload your raw data files to the HPC
2. Create a Snakemake workflow file
3. Submit a SLURM job to run the analysis
4. Return a job ID for tracking

3. Check job status

toxolib hpc-status --job-id your_job_id

4. Download results when complete

toxolib hpc-download --job-id your_job_id --output-dir ./local_results

Database Setup

Kraken2 Database

You can download the standard Kraken2 database from: https://genome-idx.s3.amazonaws.com/kraken/k2_standard_20240112.tar.gz

wget https://genome-idx.s3.amazonaws.com/kraken/k2_standard_20240112.tar.gz
tar -xzf k2_standard_20240112.tar.gz -C /path/to/kraken2/database
export KRAKEN2_DB_DIR=/path/to/kraken2/database

Corn Genome Database

For host removal, you can download the corn genome reference from: https://glwasoilmetagenome.s3.us-east-1.amazonaws.com/corn_db.zip

wget https://glwasoilmetagenome.s3.us-east-1.amazonaws.com/corn_db.zip
unzip corn_db.zip -d /path/to/corn_db

Setting up databases on HPC

When using the HPC functionality, you'll need to upload and extract these databases on your HPC system:

# On your local machine, download the databases
wget https://genome-idx.s3.amazonaws.com/kraken/k2_standard_20240112.tar.gz
wget https://glwasoilmetagenome.s3.us-east-1.amazonaws.com/corn_db.zip

# Upload to HPC (using scp)
scp k2_standard_20240112.tar.gz [e-mail]:/path/on/hpc/
scp corn_db.zip [e-mail]:/path/on/hpc/

# SSH into HPC and extract
ssh [e-mail]
mkdir -p /path/on/hpc/kraken2_db
tar -xzf /path/on/hpc/k2_standard_20240112.tar.gz -C /path/on/hpc/kraken2_db
mkdir -p /path/on/hpc/corn_db
unzip /path/on/hpc/corn_db.zip -d /path/on/hpc/corn_db

Then when running toxolib, specify these paths:

toxolib hpc -r raw_data_1.fastq.gz raw_data_2.fastq.gz -o /path/on/hpc/output_dir \
    --kraken-db /path/on/hpc/kraken2_db \
    --corn-db /path/on/hpc/corn_db

License

MIT