Effects of marine phytoplanktonic blooms spreading to succession patterns of prokaryotic viruses revealed by a microcosm experiment

The goal of this study is to reveal dynamics of prokaryotic viruses following shifts in abundant prokaryotes during marine phytoplanktonic blooms. To this end, a microcosm experiment was performed. Coastal prokaryotic and their viral community collected in Osaka bay was cultured with addition of dissolved intracellular organic matters extracted from Heterosigma akashiwo (NIES-293 strain) or Chaetoceros sp. (NIES-3717 strain), or aged seawater for control. Each triplicated flask was incubated at 20 degree Celsius with a 14.5 h-9.5 h light-dark photocycle. Samples were taken on the day 0 to day 7 during incubation. DNA extracted from prokaryotic fraction were offered for 16S rRNA (V3-V4 region) analysis. DNA extracted from viral fraction were offered for metagenomic analysis.