DNA extraction and whole-genome shotgun sequencing
Microbial DNA extraction from the fecal samples was performed using the Power Fecal DNA Isolation Kit (Mobio, USA), according to manufacturer’s protocol. WGS library was constructed according to standard True Seq WGS protocol provided by Illumina, Inc. (San Diego, USA). Library quality for fragment size distribution was checked on Bioanalyzer 2100 using high sensitivity DNA kit (Agilent technologies, USA). Library quantification was performed using a Qubit Fluorometer (Invitrogen, USA) and a Stratagene Mx3000P Real-time PCR Cycler (Agilent, USA) prior to cluster generation in a c-Bot automated sequencing system (Illumina, Inc.).