How to define fish pathogen relatives from a 16S rRNA sequence library and Pearson correlation analysis between defined OTUs from the library: Supplementary data to the research article "Presence and habitats of bacterial fish pathogen relatives in a marine salmon post-smolt RAS".

This paper provides supplementary data to the research paper ''Presence and habitats of bacterial fish pathogen relatives in a marine salmon post-smolt RAS" [1]. Here, environmental samples from a marine recirculating aquaculture system (RAS) were subjected to microbiome studies. This data article adds value to the research article by providing open access to data files that increased information retrieval from the 16S rRNA sequence library. A fasta file of full-length 16S rRNA sequences from fish pathogenic microbes was deposited in the Mendeley data repository, a collection named "Fish Pathogen Database". Alignment of this database against the short sequences in the 16S rRNA library revealed the fish pathogen-relatives. Furthermore, a link to a CSV file containing Pearson correlation data was provided, an analysis based on the relative abundance information of all operational taxonomic units defined in the microbiome dataset. Included also, the methodological description of the Pearson correlation analysis, as well as a table where correlation data for the defined fish pathogen-relatives was retrieved from the large data file (Table 1).

Microbiome dataset from a marine recirculating aquaculture system (RAS) for salmon post-smolt production in Norway.

A marine aquaculture recycling system (RAS) for the production of post-smolt was monitored for microbial community structures during the first year of operation. Sample material was obtained monthly from the biofilter biofilm carriers, the production water (tank 3), the fish skin (tank 3) and the tank 3 wall biofilm. Additional samples were taken during outbreaks of fish skin wounds, washing of the plant, UV filtration of the inlet water and from various wall biofilms. Samples for depth profiles from all fish tanks were also collected. The sampling tools were a ladle for capturing biofilter biofilm carriers, toothbrushes for wall biofilm capture, filters for capture of water microbes and scalpels for skin tissue slicing. The sampling times were indicated by the production cycle number (cycle 2-5) and the week number within the cycle (W). Prior to bacterial community analysis, the stored samples were exposed to cell lysis and extraction of environmental DNA by commercial kits. All samples were subjected for PCR amplification of 16S rDNA sequences for library formations and prepared for Ion Torrent technology, which sequences 250 bp fragments. A total of 1.1 million reads were obtained from the 100 RAS samples analysed. The process from Ion Torren analysis to library involved bioinformatics steps with sorting, filtering, adjustment and taxonomic identification, and the final output was shown in a table as operational taxonomic units (OTUs) and relative abundance at different sampling sites and sampling time points. Of a total of 450 taxonomically assigned OTUs, 45% were classified at genus level. The 16S library raw data are deposited in the Mendeley data repository and cited in this Data in Brief article co-submitted with the article "Microbial colonization and stability in a marine post-smolt RAS inoculated with a commercial starter culture." [1]. So far, the raw data are referenced in four more publications in progress. These cover microbial shifts and enrichments between sampling times, sulfur cycling, "in vivo biofilm" and identification of relatives of fish pathogens in RAS. All library sequences are available in GenBank with accession numbers MN890148-MN891672.