WGS of Gut Microbiome : Homo sapiens
Approximately 100-150 mg of fecal material from four serial stool samples (collected at week 3, months 3, 6 and 12) were used to extract genomic DNA with the ZR Fecal DNA MicroPrep Kit (Zymo Research, USA) according to the manufacturers instructions. For each stool sample, a sequencing library was first constructed using Illuminas Truseq Nano DNA Library Preparation Kit (Illumina, San Diego, USA). The samples were sheared on a Covaris E220 to ~450 bp, following the manufacturers recommendation, and uniquely tagged with one of Illuminas TruSeq HT DNA barcode combinations to enable sample pooling for sequencing. The finished libraries were quantitated using Invitrogens Picogreen assay and the average library size was determined on Bioanalyzer 2100, using a DNA 7500 chip (Agilent). Library concentrations were then normalized to 4 nM and validated by qPCR on a ViiA-7 real-time thermocycler (Applied Biosystems), using qPCR primers recommended in Illuminas qPCR protocol, and Illuminas PhiX control library as standard. The libraries were then pooled at equimolar concentrations and sequenced on an Illumina HiSeq2500