16S rRNA amplicon sequencing of S6 consortium (Generation 3)
PCR amplification of V3-V4 regions was performed by using 515F/806R primers. The PCR products with proper size were selected by 2% agarose gel electrophoresis. Same amount of PCR products from each sample was pooled, end-repaired, A-tailed and further ligated with Illumina adapters. Libraries were sequenced on a paired-end Illumina platform to generate 250bp paired-end raw reads