Viruses of the Ocean: On the Shores of the <i>Aqua Incognita</i>. Horizons of the Taxonomic Diversity

Abstract

In recent years, marine viruses have evolved into a distinct branch of virology, yet they still represent a sort of “dark matter”, and their role and significance in the evolution and functioning of Earth's biosphere remain unclear. The widespread implementation of the primerless sequencing methods in routine laboratory practice has streamlined the development of marine virology from initial observations of virus-like particles in seawater, once deemed exotic, to comprehensive generalizations that reshape our understanding of global problems in the World Ocean. They include the continuous depletion of biological resources and diversity, marine pollution, and global climate change. Nevertheless, in terms of virology, the World Ocean remains a true aqua incognita, and marine virology, as a subset of general virology, and marine biology are just at the initial stages of their development, standing on the cusp of new discoveries. Those discoveries have the potential to reveal fundamental processes in the origin and evolution of life on Earth, accelerate the development of novel technologies, and even foster innovative approaches to reshaping the noosphere. The aim of this review is to draw scientific attention to the numerous problematic aspects of viruses in the World Ocean. It covers the main topics such as the current taxonomy of marine viruses, their role in marine ecosystems, the presence of viruses in marine species and related diseases, and the role of marine viruses in the context of global climate change, focusing on unexplored area and outlining directions for future research studies.