Metagenomic analysis of surface microlayers in the Northwestern Pacific Ocean and the Bering Sea

Abstract

Surface microlayer (SML) is generally defined as a thin layer in top few millimeters of surface water in aquatic environments. The ocean SML is covering >70% of the Earth's surface and is important to understand the ocean-atmosphere interactions, such as exchange of green-house gases, production of aerosols and feasibility for remote sensing of physical parameters in oceanography. Previous studies on SML have shown a striking difference in physical, chemical and biological properties between SML and underlying water (UW; a depth of a few ten centimeters to a few meters below SML) in marine environments. SML is also interesting in a microbiological aspect because SML is exposed to strong solar (and UV) irradiation driving selective microbial colonizations and is a source of marine bioaerosols potentially impacting on cloud development, atmospheric chemistry and microbial biogeography. To investigate community structures and potential functions of SML microorganisms, two sets of SML and UW samples were collected from Northwestern Pacific Ocean and the Bering Sea and subjected to metagenomics analysis using shotgun DNA sequences. In the presentation, some results will be shown and discussed in a respect of microbial selection and adaptation to such a harsh SML environment.