Bioinformatics
FASTQ files were demultiplexed by different regions using the module in the GeneGlobe Data Analysis Center. (https://geneglobe.qiagen.com/tr/analyze). The resulting paired-end FASTQ files were used to profile the microbiota of the samples with DADA2 using default parameters. Sequencing of 16S rRNA gene(V1-V2) regions was performed 13. Amplicon sequence variants (ASV) were picked out and assigned with taxonomic annotations using the naive Bayesian classifier method embedded in DADA2 14. The Silva (v138.1) was used as a reference database (v138.1)15.