Simple bacterial assembly and annotation pipeline
nf-core/bacass is a bioinformatics best-practice analysis pipeline for simple bacterial assembly and annotation. The pipeline is able to assemble short reads, long reads, or a mixture of short and long reads (hybrid assembly).
The pipeline is built using Nextflow, a workflow tool to run tasks across multiple compute infrastructures in a very portable manner. It uses Docker/Singularity containers making installation trivial and results highly reproducible. The Nextflow DSL2 implementation of this pipeline uses one container per process which makes it much easier to maintain and update software dependencies. Where possible, these processes have been submitted to and installed from nf-core/modules in order to make them available to all nf-core pipelines, and to everyone within the Nextflow community!
On release, automated continuous integration tests run the pipeline on a full-sized dataset on the AWS cloud infrastructure. This ensures that the pipeline runs on AWS, has sensible resource allocation defaults set to run on real-world datasets, and permits the persistent storage of results to benchmark between pipeline releases and other analysis sources. The results obtained from the full-sized test can be viewed on the nf-core website.
Short Read Assembly
This pipeline is primarily for bacterial assembly of next-generation sequencing reads. It can be used to quality trim your reads using FastP and performs basic sequencing QC using FastQC. Afterwards, the pipeline performs read assembly using Unicycler. Contamination of the assembly is checked using Kraken2 to verify sample purity.
Long Read Assembly
For users that only have Nanopore data, the pipeline quality trims these using PoreChop and assesses basic sequencing QC utilizing NanoPlot and PycoQC. The pipeline can then perform long read assembly utilizing Unicycler, Miniasm in combination with Racon, or Canu. Long reads assembly can be polished using Medaka or NanoPolish with Fast5 files.
For users specifying both short read and long read (NanoPore) data, the pipeline can perform a hybrid assembly approach utilizing Unicycler, taking the full set of information from short reads and long reads into account.
Assembly QC and annotation
First, prepare a samplesheet with your input data that looks as follows:
Each row represents a fastq file (single-end) or a pair of fastq files (paired end).
Default: Short read assembly with Unicycler,
--kraken2db can be any compressed database (
Long read assembly with Miniasm:
Please provide pipeline parameters via the CLI or Nextflow
-params-file option. Custom config files including those
provided by the
-c Nextflow option can be used to provide any configuration except for parameters;
To see the results of an example test run with a full size dataset refer to the results tab on the nf-core website pipeline page. For more details about the output files and reports, please refer to the output documentation.
Contributions and Support
If you would like to contribute to this pipeline, please see the contributing guidelines.
If you use nf-core/bacass for your analysis, please cite it using the following doi: 10.5281/zenodo.2669428
An extensive list of references for the tools used by the pipeline can be found in the
You can cite the
nf-core publication as follows:
The nf-core framework for community-curated bioinformatics pipelines.
Philip Ewels, Alexander Peltzer, Sven Fillinger, Harshil Patel, Johannes Alneberg, Andreas Wilm, Maxime Ulysse Garcia, Paolo Di Tommaso & Sven Nahnsen.
Nat Biotechnol. 2020 Feb 13. doi: 10.1038/s41587-020-0439-x.