title: Microbial Biofilm
design: Amplicon libraries were prepared with a first PCR using the V4 16S SSU rRNA primers 515F 5'-GTGYCAGCMGCCGCGGTAA-3') and 806R (5'-GGACTACNVGGGTWTCTAAT-3') with overhangs matching the Nextera XT-indices [29, 30]. The PCR mix contained 14 l DNA-extract, 0,5 l 10 M forward and reverse primer and 10 l 2xKAPA HiFi Hot Start Ready-mix. The PCR was done with 3 min denaturation at 94C, 35 cycles of 45 sec denatura-tion at 94C, 60 sec annealing at 50C and 90 sec elongations at 72C, and a final elongation for 10 min at 72C. The PCR products were cleanup with Ampure XP beads at 0.8x ratio. Following cleanup and QC, we prepared an equimolar pool of the amplicon libraries which was sequenced on an MiSeq Nano V2 flow cell 2x150 bp PE.