Metagenomic sequences of petroleum contaminated soil layer: Middle layer
The 16S rRNA gene V4 region was amplified by using barcoded specific primer set 515F (5’-GTGCCAGCMGCCGCGGTAA-3’) and 806R (5’-GGACTACHVGGGTWTCTAAT-3’) with the total DNA from the petroleum contaminated soil layers as the template. PCR products from different soil layers were then gone library construction and sequencing. Sequencing libraries were generated using TruSeq DNA PCR-Free Sample Preparation Kit (Illumina, USA) following manufacturer’s recommendations, and then the libraries were sequenced on an IlluminaHiSeq 2500 platform.