Annotated MAGs (WGS) from bioaugmented biogas reactors

Biomethanation represents a promising approach for biomethane production while biofilm-based process, e.g. trickle bed reactor (TBR), is one of the most efficient solutions. There are challenges to maintain stable performance and debates between pure and mix culture approaches. This study introduces inoculum contains enriched hydrogenotrophic methanogens to TBR as bioaugmentation to access their impacts on the process and, microbial community dynamics.During the enrichment experiment, two samples were collected at start (timepoint 0), and after 1 month, 2 months and 3 months, constituting a total 8 samples for 16S rRNA gene sequencing. For metagenome sequencing, a total 12 samples were collected. Two samples were collected from the raw inoculum and two samples were collected from the enriched inoculum. Then, for the trickle bed reactor experiment, four samples were collected from the TBR-Control and four samples from the TBR-Bio. The TBR samples constituted two samples of the liquid fraction and two samples of the solid fraction/biofilm at the end of the reactor experiment. All samples for microbial analysis were frozen at -18 ^°C immediately, following shipment to a commercial company for analyses (DNASense, 9220 Aalborg, Denmark) in an insulated package containing 5 kg dry ice. The biofilm samples constituted a whole biofilm carrier (Jensen et al., 2019). DNA extraction, 16S rRNA gene sequencing, and metagenomic sequencing was performed by DNASense. Briefly, DNA for 16S rRNA gene sequencing was extracted using the FastDNA Spin Kit for Soil (MP Biomedicals, USA) and paired-end sequenced (2x300 bp) using the MiSeq platform (Illumina, USA). Similarly, DNA for whole genome sequencing was extracted using the DNeasy PowerSoil Pro Kit (Qiagen, Germany) and sequenced on the PromethION P24 platform (Oxford Nanopore Technologies, Oxford, UK).