sequences of bacteria
After extracting genomic DNA from the sample, the V3 + V4 region of 16S rDNA was amplified using specific primers with barcodes. The primer sequences are: 341F:CCTACGGGNGGCWGCAG;815R:GGACTACHVGGGTATCTAAT. The purified amplification product (i.e., amplicon) was connected to the sequencing adapter to construct a sequencing library.