Sequencing analysis
We amplified DNA extracted by polymerase chain reaction (PCR) with primer pairs, 16S Amplicon PCR Forward Primer: 5’CCTACGGGNGGCWGCAG, and 16S Amplicon PCR Reverse Primer: 5’GACTACHVGGGTATCTAATCC targeting the V3 and V4 hypervariable regions of the bacterial 16S rRNA gene [