metagenome of Homo sapiens : human gut microbiome
Fecal samples were collected using a Commode Specimen Collection System. All samples were then stored at -80C prior to processing. DNA was extracted from the fecal samples using DNeasy PowerLyzer PowerSoil Kit (Qiagen, Germantown, MD). DNA library for sequencing was prepared by Illumina HiSeq; we used the Nextera XT Index kit to attach dual index adapters. Each library was prepared by diluting the samples to 5 ng/Lm and equal volumes were mixed to 4 nM. We quantified the DNA concentration by Qubit (Thermo Fisher Scientific, USA).