16S sequence
The bacterial diversity was analyzed by amplifying the hypervariable V3-V4 region of the 16S rRNA gene using 341F and 806R primers (Gobbi et al., 2019; Takahashi et al., 2014). A 16S rRNA gene double PCR-step approach was used for Illumina sequencing library preparations (Gobbi et al., 2019). Sequencing was performed on Illuminas MiSeq platform using the V2 500 cycles reagent kit.