Major viral impact on the functioning of benthic deep-sea ecosystems

Nature. 2008 Aug 28;454(7208):1084-7. doi: 10.1038/nature07268.

Abstract

Viruses are the most abundant biological organisms of the world's oceans. Viral infections are a substantial source of mortality in a range of organisms-including autotrophic and heterotrophic plankton-but their impact on the deep ocean and benthic biosphere is completely unknown. Here we report that viral production in deep-sea benthic ecosystems worldwide is extremely high, and that viral infections are responsible for the abatement of 80% of prokaryotic heterotrophic production. Virus-induced prokaryotic mortality increases with increasing water depth, and beneath a depth of 1,000 m nearly all of the prokaryotic heterotrophic production is transformed into organic detritus. The viral shunt, releasing on a global scale approximately 0.37-0.63 gigatonnes of carbon per year, is an essential source of labile organic detritus in the deep-sea ecosystems. This process sustains a high prokaryotic biomass and provides an important contribution to prokaryotic metabolism, allowing the system to cope with the severe organic resource limitation of deep-sea ecosystems. Our results indicate that viruses have an important role in global biogeochemical cycles, in deep-sea metabolism and the overall functioning of the largest ecosystem of our biosphere.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomass
  • Carbon / metabolism
  • Ecosystem*
  • Geologic Sediments / virology
  • Heterotrophic Processes
  • Hydrostatic Pressure
  • Microbial Viability
  • Oceans and Seas
  • Prokaryotic Cells / cytology
  • Prokaryotic Cells / metabolism
  • Prokaryotic Cells / virology
  • Seawater / virology*
  • Virus Physiological Phenomena*
  • Viruses / isolation & purification
  • Viruses / metabolism

Substances

  • Carbon