big city  1
DNA was extracted from mouse stool using the Purelink  Microbiome DNA Purification kit (Invitrogen). Metagenomic NGS and bioinformatic analysis were performed by BMKGene (Biomarker Technologies, Beijing, China). The amplification of V3-V4 region of the 16S rRNA gene for the library preparation were done with 338F and 806R primers.