pip install kraken-db-builder
kdb --help
kraken-db-builder --help
To create standard Kraken2 database
kdb --db-type standard
Before creating a standard database, you can try a smaller database like fungi.
kdb --db-type fungi
To use locally downloaded files, run the following command
kdb --db-name k2_test --genomes-dir /path/to/genomes --taxonomy-dir /path/to/taxonomy
To limit the number of genomes in the database, use the --limit
option
kdb --db-name k2_test_100 --genomes-dir /path/to/genomes --limit 1000
kdb was aimed to created to provide a simple and easy to use tool to build wide variety of databases with a single command.
Why not kraken2-build?
kraken2-build is a tool provided by Kraken2 to build Kraken2 database. It is a great tool but it is limited to build only Kraken2 database. kdb is a more generic tool which can be used to build databases for Kraken2, Centrifuge, Bracken, etc.