Soil metagenome  at the middle of Tiser cave(2)
total environment DNA was extracted from 1 g of soil samples using DNeasy PowerSoil Isolation Kit (QIAGEN Cat. No: 47014). The quality and quantity of DNA were checked on agarose gel (8% w/v) and through NanoDrop ND-1002 spectrophotometer. Library was builded by BGI (Beijing Genomics Institute, Shenzhen, China).