METAGENOMICS FOR STUDY DIVERSITY OF MICROBIAL POPULATIONS IN CENTRAL GULF OF THAILAND

Abstract

Metagenomics is a useful technique to study microbial diversity directly in a culture-independent manner. Thus, metagenomics finds nearly 100% of all microorganisms in the environment. This approach becomes a major tool to analyze the microbial diversity (microbiota) worldwide. This research studied the diversity of microbial populations, including prokaryotes and eukaryotes, in the central Gulf of Thailand, using metagenomics combined with 16S and 18S rRNA gene sequencing. The research area covers various geographic coordinate throughout the central Gulf of Thailand, at the sea surface (<5 m from the sea surface) and a seafloor (1 m above the seafloor), during March to April (dry season) of 2013. The communities, both prokaryotes and eukaryotes, were determined homogeneous, by the function of the program Mothur (get.communitytype). Yet, some abiotic factors were found to affect the prokaryote population: temperature (p=0.012) and for eukaryote population fluorescence Seapoint (p=0.029) and salinity (p=0.004). Significant representative OTUs in prokaryotes were Pseudoalteromonadaceae and Oceanospirillacea; and eukaryotes were Bilateria, Euglenida, and Cnidaria. Moreover, the direction of water circulation and the type of organisms might affect the microbial diversity, observed possible correlation in PCoA. Overall, this research successfully studied the microbial diversity of the dry season; meanwhile does not represent other seasons. Therefore, it is advisable to also study the diversity of microbes in other seasons as well.