16S rRNA is a component of the 30S small subunit of the ribosome in prokaryotic cells, containing 9 hypervariable regions (V1-V9).Since 16S rDNA amplicon sequencing typically selects one or several hypervariable regions of interest, the universal primer used during PCR amplification is designed from the conservative regions that encompass the hypervariable regions of interest, which will allow for the identification of microorganisms from the hypervariable regions through subsequent analysis (Caporaso et al., 2011; Youssef et al., 2009; Hess et al., 2011).With the continuous development of high-throughput sequencing platforms, the PE250 sequencing strategy can be realized through the upgraded Illumina sequencing platform.

In the process from DNA samples to final data, each step such as sample test, PCR, purification, library preparation, and sequencing will affect the quality and quantity of data, while the data quality will directly affect the subsequent information analysis results. In order to keep the accuracy and reliability of sequencing data, quality control (QC) is performed at each step of the procedure.