2.3. 16S rRNA Sequencing and Bacterial Identification

To identify pure-cultured bacteria, total genomic DNA was extracted from single colony of the bacteria using the DNeasy^® Blood & Tissue Kit (Qiagen, Valencia, CA, USA), following the manufacturer’s protocol. Universal primers targeting the 16S rRNA gene of the bacteria were used for PCR, under conditions reported previously. For gene sequence analysis, the PCR products were sent to the genomic division of Macrogen (Seoul, Korea), where nucleotide sequencing was performed using the ABI PRISM 3730XL Analyzer with the BigDye^® Terminator v3.1 Cycle Sequencing Kit (Applied Biosystems, Waltham, MA, USA). The sequence of the 16S rRNA gene was compared to other available 16S rRNA genes by the NCBI blast search and using the EzBioCloud server (https://www.ezbiocloud.net/) to identify similar subspecies of bacteria. For accurate identification of the bacteria, the freshly cultured bacteria on TSA media were used for bacterial identification using MALDI-TOF Biotyper 3 (Bruker, Billerica, MA, USA). In addition, to confirm the identification result, the genomic DNA of bacteria was extracted and analyzed by PCR using specific primers [15] to detect partial soda, a house-keeping gene of the bacteria.