metagenome of ocean water
The quality of DNA extract quality was checked on agarose gel (1%), and then fragmented to an average size (~300 bp) using Covaris M220 (Gene Company Limited, China) for paired-end library construction. Then, paired-end sequencing was performed on Illumina HiSeq4000 platform at Majorbio Bio-Pharm Technology Co., Ltd. (Shanghai, China).