[A-OS17] Marine microbial ecology

[AOS17-02] Development of a scheme for analyzing individual marine sinking particles

*Tatsuhiko Hoshino^1,2, Yosuke Yamada^1,2, Ryo Takahashi³, Fumio Inagaki^2,1 (1.Japan Agency for Marine-Earth Science and Technology, 2.WPI-AIMEC, 3.Marine Works Japan LTD)

Keywords:Marine particle, Microbial community, Metagenome

Particulate organic matter (POM) plays crucial roles in transport and sequestration of carbon in the marine environment. Approximately 80% of the carbon exported from eutrophic zones is carried by these particles. Furthermore, due to biological processes, POM flux in the mesopelagic zone declines by approximately 85%.
These particles function as hotspots of microbial activity within the water column. Microorganisms attached to POM exhibit higher cell densities, accelerated growth rates, enhanced extracellular enzyme activities, greater metabolic diversity, and elevated rates of biogeochemical transformation compared to their free-living counterparts. Therefore, it is pivotal to elucidate the interactions between marine particles and their associated microbial communities to better understand carbon cycling and biogeochemical processes in the ocean.
The composition and function of microbial communities inhabiting marine particles are likely to vary depending on physical factors, such as the size and density of the particles, and chemical factors, including the chemical composition of the particles themselves. To study individual marine particles, we are developing an analytical scheme that involves isolating single particles via laser microdissection, followed by DNA amplification and subsequent amplicon/metagenome sequencing. In this presentation, we will share preliminary results on microbial community composition and metagenomic analysis of these particles, and discuss their roles in the ocean's material cycle.