Succession of bacterioplankton community composition in an enclosed bay(Omura bay).. marine plankton metagenome

We aimed at clarifying planktonic bacterial community composition in an enclosed bay (Omura bay) which consistently experiences hypoxia every summer. Water samples were collected from three depths (surface, middle, and bottom layers of water column) during May through September 2015 and April through October 2016. Samples in 2015 were collected from center of Omura bay. On the other hand, Samples in 2016 were collected from north, center, south and inner part of the bay. In addition, samples of a pelagic sea near Omura bay were also collected in 2016. Each sample (1L) was filtered through 0.22 micro meter filter (Sterivex), preserved in 10 ? TE buffer and kept frozen at -20 degree celsius. Genomic DNA was extracted with Pure Gene kit (Gentra systems, Quigen) from the frozen samples in less than one month after sampling. Procedure for the DNA extraction was based on the protocols described MIRADA project. The DNA extracts were sent to MacroGen Japan for Illumina Miseq amplicon sequence with V3-V4 regions of the bacterial 16S rDNA.