design: Metagenomic sequencing was performed on an Illumina MiSeq platform (Illumina) targeting 16S rRNA V3 and V4 regions according to manufacturer protocols. Briefly, 16S Amplicon PCR primers used are as following: 5 TCGTCGGCAGCGTCAGATGTGTATAAGAGACAGCCTACGGGNGGCWGCAG 3 and 5 GTCTCGTGGGCTCGGAGATGTGTATAAGAGACAGGACTACHVGGGTATCTAATCC 3. PCR products were cleaned using AMPure XP beads before Illumina sequencing adapters were added with the Nextera XT Index kit. The library was cleaned again using the AMPure XP beads prior to quantification using automated electrophoresis with TapeStation System (Agilent). The MiSeq v3 reagent kit (Illumina) was used according to the manufacturers protocol for sequencing.