README.md

PCN-db-pipeline by Rohan Maddamsetti and Maggie Wilson.

Requirements: biopython, kallisto, SRA-Toolkit, pysradb, and ncbi-datasets-cli

This program can either be run locally or on Duke Compute Cluster (DCC). DCC is suggested to use due to the large amount of data that is downloaded from the thousands of samples.

Make a top-level directory with three directories inside, named "data", "results", and "src". Now copy all source code files in this repository into "src".

The following file needs to be downloaded into the data/ directory.

data/prokaryotes.txt should be downloaded from: https://ftp.ncbi.nlm.nih.gov/genomes/GENOME_REPORTS/prokaryotes.txt

results/prokaryotes-with-chromosomes-and-plasmids.txt should then be generated with the following command (run from src/ directory):

(head -n 1 ../data/prokaryotes.txt && grep "plasmid" ../data/prokaryotes.txt | grep "chromosome") > ../results/prokaryotes-with-chromosomes-and-plasmids.txt

This command ensures that every genome has both an annotated chromosome and at least one annotated plasmid.

SRA data for ~6000 genomes was downloaded, but only have about ~4500 reference genomes. to understand this discrepancy, I ran: cd ../data/NCBI-reference-genomes ls | grep ".gbff.gz" | sed 's/_genomic.gbff.gz$//' > ../../results/downloaded-genome-ids.txt

Expected Output:

The first steps of this pipeline, convert these sample IDs into run accession IDs and create the reference genome path. Two txt files, a table with run accession IDs and a list of the genome paths will be created. Then, the sample's reference genome will be downloaded if a run accession ID is present, these genomes will be downloaded into the ref-genomes folder in results. There should be 4,540 genomes downloaded, as that is the number of samples that have a run ID.

A metadata csv is then created, a master list of all the samples were are downloading data for. Next, fastq files are downloaded for each run ID and put into the SRA folder in results.

The next several functions parse through the SRA and reference genomes using kallisto and themisto.

Lastly the final tables of results are created as "PIRA-PCN-estimates.csv", and "NCBI-replicon_lengths.csv".

How to run on DCC or locally.

create a new conda environment (here I clone the base environment):

conda create --name PCNdb_env --clone base

conda activate PCNdb_env

install pysradb and biopython in this environment using pip:

pip install pysradb

pip install biopython

install kallisto and ncbi-datasets-cli in this new environment

conda install bioconda::kallisto

conda install conda-forge::ncbi-datasets-cli

conda install bioconda::breseq

You will then need to load the SRA-Toolkit module that is available on DCC:

module load SRA-Toolkit

alternatively, install a pre-built binary of SRA-Toolkit on your machine from here: https://github.com/ncbi/sra-tools

This will take ~2 weeks to run on DCC.

The Illumina data download (stage 3) takes 281 hours (12 days) to download 15 TB of raw sequencing data from NCBI Short Read Archive (SRA).

sbatch --mem=16G -t 430:00:00 -p youlab --wrap="python PCN_pipeline.py"

Use .../work, as ~15 terabytes will be downloaded.