ConFindr

This program is designed to find bacterial intra-species contamination in raw Illumina data. It does this by looking for multiple alleles of core, single copy genes.

For complete instructions on installation and usage, please visit the ConFindr GitHub Pages site.

Important Note

ConFindr has only been validated using rMLST databases. Please use them if possible (--rmlst). Complete installation instructions can be found here.

Quickstart

Installing ConFindr

1. Follow the instructions here to add the Bioconda channel to your list of conda channels, if it hasn’t already been added.

2. Install ConFindr into a new conda environment named ‘confindr’:

conda create -n confindr -c bioconda confindr=0.8.2

3. Activate the new conda environment:

conda activate confindr

Downloading and setting up the rMLST databases

Instructions for downloading and setting up the rMLST databases can be found here.

Testing ConFindr

1. To obtain an example dataset, run the following command, which will create a folder named test_samples in your current working directory:

wget https://figshare.com/ndownloader/files/41228577 -O test_samples.tar.gz && \
    tar -xzvf test_samples.tar.gz && \
    rm test_samples.tar.gz

2. As of version 0.7.0 ConFindr can be run automatically on Escherichia, Salmonella, and Listeria with no further work on your part, using core-gene databases (experimental). Simply run:

confindr -i test_samples -o test_out

3. To use the recommended rMLST database (after installation):

confindr -i test_samples -o test_out --rmlst

The results for this analysis can be found within test_out/confindr_report.csv. More extensive tests can be performed by following the instructions here.

If you want to run ConFindr on genera other than the 3 listed above, you’ll need to get access to and download the rMLST databases by following the instructions here.

Running ConFindr in a Python Script

If you want to run ConFindr from within a script instead of running from the command line, here’s how:

from confindr_src import confindr

# Find read files.
paired_reads = confindr.find_paired_reads('path_to_fastq_folder', forward_id='_R1', reverse_id='_R2')
# Run confindr. This assumes that you have already downloaded the databases. If you haven't,
# you can run confindr.check_for_databases_and_download(database_location='path/where/you/want/to/download, tmpdir='a/tmp/dir')
for pair in paired_reads:
    confindr.find_contamination(pair=pair,
                                forward_id='_R1', # change if yours is different
                                threads=4, 
                                output_folder='path/to/output',
                                databases_folder='path/to/databases')
                                

Reporting Issues

If you have any problems installing or running ConFindr, or have feature request, please open an issue here on GitHub.

Citing ConFindr

ConFindr has been published in PeerJ—if you use it in your work, please cite the following:

Low AJ, Koziol AG, Manninger PA, Blais B, Carrillo CD. 2019. ConFindr: rapid detection of intraspecies and cross-species contamination in bacterial whole-genome sequence data. PeerJ 7:e6995 https://doi.org/10.7717/peerj.6995