AMPLICON of mice: feces
Total genomic DNA was extracted using MagPure Soil DNA LQ Kit, and the diluted DNA was used as template for PCR amplification of bacterial 16S rRNA (V3-V4) genes with the barcoded primers and Takara Ex Taq (Takara). Amplicon quality was visualized using gel electrophoresis, purified with AMPure XP beads (Agencourt), and amplified for another round of PCR. After purified with the AMPure XP beads again, the final amplicon was quantified using Qubit dsDNA assay kit. Equal amounts of purified amplicon were pooled for subsequent sequencing.