Viral abundance, decay, and diversity in the meso- and bathypelagic waters of the North Atlantic

Author(s)
Verónica Parada, Eva Sintes, Hendrik M. Van Aken, Markus G. Weinbauer, Gerhard J. Herndl
Abstract

To elucidate the potential importance of deep-water viruses in controlling the meso- and bathypelagic picoplankton community, the abundance, decay rate, and diversity of the virioplankton community were determined in the meso- and bathypelagic water masses of the eastern part of the subtropical North Atlantic. Viral abundance averaged 1.4 × 106 ml-1 at around 100 m of depth and decreased only by a factor of 2 at 3,000 to 4,000 m of depth. In contrast, picoplankton abundance decreased by 1 order of magnitude to the Lower Deep Water (LDW; 3,500- to 5,000-m depth). The virus-to-picoplankton ratio increased from 9 at about 100 m of depth to 110 in the LDW. Mean viral decay rates were 3.5 × 10-3 h-1 between 900 m and 2,750 m and 1.1 × 10-3 h-1 at 4,000 m of depth, corresponding to viral turnover times of 11 and 39 days, respectively. Pulsed-field gel electrophoresis fingerprints obtained from the viral community between 2,400 m and 4,000 m of depth revealed a maximum of only four bands from 4,000 m of depth. Based on the high viral abundance and the low picoplankton production determined via leucine incorporation, we conclude that the viral production calculated from the viral decay is insufficient to maintain the high viral abundance in the deep North Atlantic. Rather, we propose that substantial allochthonous viral input or lysogenic or pseudolysogenic production is required to maintain the high viral abundance detected in the meso- and bathypelagic North Atlantic. Consequently, deep-water prokaryotes are apparently far less controlled in their abundance and taxon richness by lytic prokaryotic phages than the high viral abundance and the virus-to-picoplankton ratio would suggest.

Organisation(s)
External organisation(s)
Royal Netherlands Institute for Sea Research, Université Paris VI - Pierre-et-Marie-Curie
Journal
Applied and Environmental Microbiology
Volume
73
Pages
4429-4438
No. of pages
10
ISSN
0099-2240
DOI
https://doi.org/10.1128/AEM.00029-07
Publication date
07-2007
Peer reviewed
Yes
Austrian Fields of Science 2012
106021 Marine biology
ASJC Scopus subject areas
Biotechnology, Food Science, Applied Microbiology and Biotechnology, Ecology
Sustainable Development Goals
SDG 14 - Life Below Water
Portal url
https://ucris.univie.ac.at/portal/en/publications/viral-abundance-decay-and-diversity-in-the-meso-and-bathypelagic-waters-of-the-north-atlantic(8be5f389-b663-4673-8ddc-ed749e74aa13).html