海水中のもっとも小さな生物因子

水圏ウイルスの生態学

抄録

Since the discovery of an extremely high abundance of viruses in marine environments in late 1980's, their ecological roles and scientific importance have been of great interest. Most marine viruses are considered to be bacteriophages and cyanophages, which have significant impact on the global biogeochemical cycle. Marine viruses also include viruses infectious to eukaryotic microalgae (=algal viruses). The genomic and physiological analysis of algal viruses showed that they are remarkably different from previously known viruses; hence, poverty in the marine virus sequence database has been a problem. On the other hand, their potential importance as genetic resources has recently been highlighted. Algal viruses are also important for controlling phytoplankton dynamics, especially for bloom-forming species. In addition, marine viruses have been studied from the viewpoint of industrial applications, e.g. microbiological agents for eliminating harmful blooms and fish diseases caused by bacteria. Marine virus study is still in its infant stage; further intensive research will shed light on the importance of viruses in marine environments.