DADA2 formatted 16S rRNA gene sequences for both bacteria & archaea

These two combined bacterial and archaeal 16S rRNA gene sequence databases were collated from various sources and formatted for the purpose of using the "assignTaxonomy" command within the DADA2 pipeline. RefSeq+RDP: This database contains 14676 bacterial & 660 archaea full 16S rRNA gene sequences. It was compiled in 14/05/2018 from predominantly the NCBI RefSeq 16S rrna database (https://www.ncbi.nlm.nih.gov/refseq/targetedloci/16S_process/) and was supplemented with extra sequences from the RDP database (https://rdp.cme.msu.edu/misc/resources.jsp). Genome Taxonomy Database (GTDB): The new version of our dada2 formatted GTDB reference sequences now contains 21965 bacteria and 1126 archaea full 16S rRNA gene sequences. If you wonder why there are fewer species with 16S rRNA, that is because some metagenomics assembled genomes (MAGs) lack the 16S gene and thus cannot be extracted. The database was downloaded from https://data.ace.uq.edu.au/public/gtdb/data/releases/release95/ on 19/07/2020. Please read the release notes and file descriptions. The formatting to DADA2 format of the databases was done using a simple awk bash scripts. The script takes as input a fasta file as provided by the core databases creators and then it outputs a fasta file with all 7 taxonomy ranks separated by ";" as required for DADA2 compatibility. Additionally, we have concatenated the unique sequence ID be it NCBI/RDP or GTDB ID to the species entry. We see this as an important QC step to highlight the issues/confidence associated with short read taxonomy assignment at the more finer rank levels.