title: 16S metabarcoding of the surface of a smear-ripened cheese: after wash 4 replicate A
design: After total microbial DNA extraction directly from the cheese surface, PCR amplification (30 cylces) of the V3-V4 regions of the 16S rRNA gene was performed with the primers V3F (5-ACGGRAGGCWGCAG-3) and V4R (5-TACCAGGGTATCTAATCCT-3) carrying the Illumina 5-CTTTCCCTACACGACGCTCTTCCGATCT-3 and the 5-GGAGTTCAGACGTGTGCTCTTCCGATCT-3 tails, respectively. Amplicons were purified using a magnetic beads CleanPCR and sample multiplexing was performed by adding tailor-made 6 bp unique indexes during a second PCR step (12 cycles). After purification and quantification, all libraries were pooled with equal amounts and the mixture was loaded onto the Illumina MiSeq cartridge according to the manufacturers instructions using MiSeq Reagent Kit v3 (2  250 bp paired-end reads).