Metagenome of marine water: viral fraction
DNA was extracted with phenol-chloroform followed by precipitatation in ethanol from the viral fractions obtained from 3L of marine water with Pellicon XL50 cassette with 100 kDa cutoff (Millipore) and precipitated in PEG 8000 (10% w/v) and NaCl (1 M).  NGS libraries were made using NEBNext Ultra II DNA Library Prep kit (NEB).