title: 16s RNA sequencing of colon sample from mus musculus
design: Bacterial 16S rRNA sequencing and data analysis were performed as described previously. The bacterial DNA was extracted using the PowerMax (stool/soil) DNA isolation kit (MoBio Laboratories, Carlsbad). Then, PCR amplification of the bacterial 16S rRNA genes V4 region was performed using the designated primer (the forwardprimer: 5GTGCCAGCMGCCGCGGTAA3 and the reverse primer: 5GGACTACHVGGGTWTCTAAT3) and Phusion High-Fidelity PCR Master Mix. After the individual quantification step, amplicons of samples were sequenced on the Illumina HiSeq 4000 platform (Guheinfo, China). The Quantitative Insights Into Microbial Ecology (QIIME, v1.9.0, http://qiime.org/) was used to process the sequencing data. Sequences with 97% similarity were assigned to the same operational taxonomic units (OTUs). Quality control and taxonomic classification of OTUs were conducted by Vsearch (v2.4.4, https://github.com/torog nes/vsearch) to search the representative sequences according to the Greengene database. OTU table was further generated to record the abundance of each OTU in each sample and thetaxonomy of these OTUs.