Marine viruses | EPFL Graph Search

Are you an EPFL student looking for a semester project?

Work with us on data science and visualisation projects, and deploy your project as an app on top of GraphSearch.

Marine viruses are defined by their habitat as viruses that are found in marine environments, that is, in the saltwater of seas or oceans or the brackish water of coastal estuaries. Viruses are small infectious agents that can only replicate inside the living cells of a host organism, because they need the replication machinery of the host to do so. They can infect all types of life forms, from animals and plants to microorganisms, including bacteria and archaea. When not inside a cell or in the process of infecting a cell, viruses exist in the form of independent particles called virions. A virion contains a genome (a long molecule that carries genetic information in the form of either DNA or RNA) surrounded by a capsid (a protein coat protecting the genetic material). The shapes of these virus particles range from simple helical and icosahedral forms for some virus species to more complex structures for others. Most virus species have virions that are too small to be seen with an optical microscope. The average virion is about one one-hundredth the linear size of the average bacterium. A teaspoon of seawater typically contains about fifty million viruses. Most of these viruses are bacteriophages which infect and destroy marine bacteria and control the growth of phytoplankton at the base of the marine food web. Bacteriophages are harmless to plants and animals but are essential to the regulation of marine ecosystems. They supply key mechanisms for recycling ocean carbon and nutrients. In a process known as the viral shunt, organic molecules released from dead bacterial cells stimulate fresh bacterial and algal growth. In particular, the breaking down of bacteria by viruses (lysis) has been shown to enhance nitrogen cycling and stimulate phytoplankton growth. Viral activity also affects the biological pump, the process which sequesters carbon in the deep ocean. By increasing the amount of respiration in the oceans, viruses are indirectly responsible for reducing the amount of carbon dioxide in the atmosphere by approximately 3 gigatonnes of carbon per year.

About this result

This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.

Related publications (70)

Related people (26)

Related units (14)

Related concepts (11)

Related lectures (9)

Benchmarking informatics approaches for virus discovery: caution is needed when combining in silico identification methods

Jaspreet Singh Saini

Understanding the ecological impacts of viruses on natural and engineered ecosystems relies on the accurate identification of viral sequences from community sequencing data. To maximize viral recovery from metagenomes, researchers frequently combine viral ...

Washington2024

Surfactant Treatment for Efficient Gene Detection of Enteric Viruses and Indicators in Surface Water Concentrated by Ultrafiltration

Shotaro Torii

The hollow fiber ultrafiltration (HFUF)-based microbial concentration method is widely applied for monitoring pathogenic viruses and microbial indicators in environmental water samples. However, the HFUF-based method can co-concentrate substances that inte ...

SPRINGER2023

What happens to biomass burning-emitted particles in the ocean? A laboratory experimental approach based on their tracers

Christos Panagiotopoulos

Wildfires, controlled burns, and biofuel combustion (biomass burning or BB) are major contributors to particulate matter in the atmosphere and thus have an impact on climate, human health, and ecosystems. Once emitted, the particulate matter derived from B ...

Amsterdam2023

Marine biogeochemical cycles

Marine biogeochemical cycles are biogeochemical cycles that occur within marine environments, that is, in the saltwater of seas or oceans or the brackish water of coastal estuaries. These biogeochemical cycles are the pathways chemical substances and elements move through within the marine environment. In addition, substances and elements can be imported into or exported from the marine environment. These imports and exports can occur as exchanges with the atmosphere above, the ocean floor below, or as runoff from the land.

Viral shunt

The viral shunt is a mechanism that prevents marine microbial particulate organic matter (POM) from migrating up trophic levels by recycling them into dissolved organic matter (DOM), which can be readily taken up by microorganisms. The DOM recycled by the viral shunt pathway is comparable to the amount generated by the other main sources of marine DOM. Viruses can easily infect microorganisms in the microbial loop due to their relative abundance compared to microbes.

Marine primary production

Marine primary production is the chemical synthesis in the ocean of organic compounds from atmospheric or dissolved carbon dioxide. It principally occurs through the process of photosynthesis, which uses light as its source of energy, but it also occurs through chemosynthesis, which uses the oxidation or reduction of inorganic chemical compounds as its source of energy. Almost all life on Earth relies directly or indirectly on primary production. The organisms responsible for primary production are called primary producers or autotrophs.

Biomass: Introduction ME-409: Energy conversion and renewable energy

Covers the introduction of biomass, its types, structure, composition, and carbon-neutral aspect.

Biomass Conversion: TVN ME-409: Energy conversion and renewable energy

Discusses the potential of biomass as a renewable energy source and its various uses.

Silica Biomineralization: Diatoms, Radiolarians, Sponges

Delves into silica biomineralization in diatoms, radiolarians, and sponges, exploring their origin, distribution, and impact on the ocean's silica cycle.