title: Biofilm Metagenomic
design: The swabbed samples were subjected to cell lysis and subsequent DNA extraction protocols, using the magnetic beads technique with a proprietary protocol (Neoprospecta Microbiome Technologies, Brazil) . The isolated microorganisms were diluted on 10 scale for DNA analysis and on a log scale to determine the colony forming units (CFU). Additionally, molecules of synthetic DNA were inserted into some samples prior to DNA extraction and at different concentrations (~600; 6,000; and 60,000 molecules) to evaluate their recovery profile after sequencing. Bacterial identifications were performed using high-throughput sequencing of the V3/ V4 regions of the 16S rRNA gene. Sequencing was performed on the MiSeq equipment (Illumina Inc., USA) using the single-end 300-cycle V2 kit, without library normalization. The DNA sequences of the microorganisms were analysed through a proprietary pipeline (Neoprospecta Microbiome Technologies, Brazil), considering a maximum of 1.0% accumulated error in the sequencing. To identify the microorganisms present in the samples, the DNA sequences were compared with a database containing other DNA sequences already characterized for the species of interest.