library_construction_protocol: Total microbial DNA of fecal samples isolated according to the QIAamp Fast DNA Stool Mini Kit.The V3-V4 hypervariable regions of bacteria 16S rRNA genes were amplified with universal primers 338F (ACTCCTACGGGAGGCAGCAG) and 806R (GGACTACHVGGGTWTCTAAT). submitted_instrument_model: Illumina NextSeq 2000