Dataset Information

Virus decomposition provides an important contribution to benthic deep-sea ecosystem functioning.

ABSTRACT: Viruses are key biological agents of prokaryotic mortality in the world oceans, particularly in deep-sea ecosystems where nearly all of the prokaryotic C production is transformed into organic detritus. However, the extent to which the decomposition of viral particles (i.e., organic material of viral origin) influences the functioning of benthic deep-sea ecosystems remains completely unknown. Here, using various independent approaches, we show that in deep-sea sediments an important fraction of viruses, once they are released by cell lysis, undergo fast decomposition. Virus decomposition rates in deep-sea sediments are high even at abyssal depths and are controlled primarily by the extracellular enzymatic activities that hydrolyze the proteins of the viral capsids. We estimate that on a global scale the decomposition of benthic viruses releases ?37-50 megatons of C per year and thus represents an important source of labile organic compounds in deep-sea ecosystems. Organic material released from decomposed viruses is equivalent to 3 ± 1%, 6 ± 2%, and 12 ± 3% of the input of photosynthetically produced C, N, and P supplied through particles sinking to bathyal/abyssal sediments. Our data indicate that the decomposition of viruses provides an important, previously ignored contribution to deep-sea ecosystem functioning and has an important role in nutrient cycling within the largest ecosystem of the biosphere.

SUBMITTER: Dell'Anno A

PROVIDER: S-EPMC4413343 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Virus decomposition provides an important contribution to benthic deep-sea ecosystem functioning.

Dell'Anno Antonio A Corinaldesi Cinzia C Danovaro Roberto R

Proceedings of the National Academy of Sciences of the United States of America 20150406 16

Viruses are key biological agents of prokaryotic mortality in the world oceans, particularly in deep-sea ecosystems where nearly all of the prokaryotic C production is transformed into organic detritus. However, the extent to which the decomposition of viral particles (i.e., organic material of viral origin) influences the functioning of benthic deep-sea ecosystems remains completely unknown. Here, using various independent approaches, we show that in deep-sea sediments an important fraction of ...[more]

PMID: 25848024

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Dataset Information

Virus decomposition provides an important contribution to benthic deep-sea ecosystem functioning.

Publications

Virus decomposition provides an important contribution to benthic deep-sea ecosystem functioning.

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