V3-V4 regions of the 16S rRNA gene of Bacteria: Euthynnus sp. fermented entrail fish
DNA from the Tai-pla sample was extracted using the QIAamp Fast DNA stool mini kit (Qiagen, Hilden, Germany), following the manufacturers instructions. DNA concentration and purity were measured using a NanoDrop One Spectrophotometer (Thermo Fisher Scientific, Waltham, MA) and by 1% agarose electrophoresis. Subsequently, each DNA sample was diluted to a final concentration of 1 ng/L with sterile water. The V3-V4 regions of the gene were amplified using universal region-specific primers 341F (5-CCT AYG GGR BGC ASC AG-3) and 806R (5-GGA CTA CNN GGG TAT CTA AT-3) tagged with sample-identifying barcodes. PCR products of the proper size were selected by 2% agarose gel electrophoresis. The DNA fragments were end-repaired and A-tailed then further ligated with Illumina adapters. The libraries were generated and sequenced on a paired-end Illumina platform.