the sample of JQ8pA group
Total bacterial DNA were extracted from mixtures of sediment and overlying water. DNA Integrity and concentration were determined using 1.2% agarose gel electrophoresis and spectrophotometry. The V3-V4 region of 16S rRNA gene was amplified with the primer pair 338f and 806r in which combined with adapter sequences and barcode sequences. PCR amplification was performed two times. Then all PCR products were pooled and purified. Purified amplicons were quantified using the HS-DNA Quant-it? dsDNA HS Assay Kit and paired-end sequenced on an Illumina Hiseq2500 platform.