title: NGS_human facial: 026
design: Bacterial DNA was extracted from skin swab samples using the QIAamp Mini Kit (QIAGEN, Hilden, Germany) according to the manufacturer's instructions. The V3-V4 variable regions of the 16S rRNA gene were amplified using the following primers: 341F (5-CCTACGGGNGGCWGCAG-3) and 805R (5-GACTACHVGGGTATCTAATCC-3). The amplified products were purified using AMPure XP beads (Beckman Coulter, Krefeld, Germany). Index sequences were added to the purified amplicons using the Nextera XT Index Kit (Illumina, CA, USA). The final libraries for each sample were normalized and pooled. Sequencing was performed using the MiSeq Reagent Kit v3 (600 cycles) on an Illumina MiSeq platform with 2  300 bp paired-end reads, as previously described.