This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Weinbauer, M. G.
Right arrow Articles by Höfle, M. G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Weinbauer, M. G.
Right arrow Articles by Höfle, M. G.
Agricola
Right arrow Articles by Weinbauer, M. G.
Right arrow Articles by Höfle, M. G.

 Previous Article  |  Next Article 

Appl Environ Microbiol, February 1998, p. 431-438, Vol. 64, No. 2
0099-2240/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

Significance of Viral Lysis and Flagellate Grazing as Factors Controlling Bacterioplankton Production in a Eutrophic Lake

Markus G. Weinbauer* and Manfred G. Höfle

GBF---National Research Center of Biotechnology, AG Molecular Microbial Ecology, D-38124 Braunschweig, Germany

Received 19 August 1997/Accepted 14 November 1997

The effects of viral lysis and heterotrophic nanoflagellate (HNF) grazing on bacterial mortality were estimated in a eutrophic lake (Lake Plußsee in northern Germany) which was separated by a steep temperature and oxygen gradient into a warm and oxic epilimnion and a cold and anoxic hypolimnion. Two transmission electron microscopy-based methods (whole-cell examination and thin sections) were used to determine the frequency of visibly infected cells, and a model was used to estimate bacterial mortality due to viral lysis. Examination of thin sections also showed that between 20.2 and 29.2% (average, 26.1%) of the bacterial cells were empty (ghosts) and thus could not contribute to viral production. The most important finding was that the mechanism for regulating bacterial production shifted with depth from grazing control in the epilimnion to control due to viral lysis in the hypolimnion. We estimated that in the epilimnion viral lysis accounted on average for 8.4 to 41.8% of the summed mortality (calculated by determining the sum of the mortalities due to lysis and grazing), compared to 51.3 to 91.0% of the summed mortality in the metalimninon and 88.5 to 94.2% of the summed mortality in the hypolimnion. Estimates of summed mortality values indicated that bacterial production was controlled completely or almost completely in the epilimnion (summed mortality, 66.6 to 128.5%) and the hypolimnion (summed mortality, 43.4 to 103.3%), whereas in the metalimnion viral lysis and HNF grazing were not sufficient to control bacterial production (summed mortality, 22.4 to 56.7%). The estimated contribution of organic matter released by viral lysis of cells into the pool of dissolved organic matter (DOM) was low; however, since cell lysis products are very likely labile compared to the bulk DOM, they might stimulate bacterial production. The high mortality of bacterioplankton due to viral lysis in anoxic water indicates that a significant portion of bacterial production in the metalimnion and hypolimnion is cycled in the bacterium-virus-DOM loop. This finding has major implications for the fate and cycling of organic nutrients in lakes.


* Corresponding author. Mailing address: GBF---National Research Center of Biotechnology, AG Molecular Microbial Ecology, Mascheroder Weg 1, D-38124 Braunschweig, Germany. Phone: 49-531-6181-440. Fax: 49-531-6181-411. E-mail: mgw{at}gbf.de.




This article has been cited by other articles:

  • Eiler, A., Bertilsson, S. (2007). Flavobacteria Blooms in Four Eutrophic Lakes: Linking Population Dynamics of Freshwater Bacterioplankton to Resource Availability. Appl. Environ. Microbiol. 73: 3511-3518 [Abstract] [Full Text]  
  • Young, K. D. (2006). The Selective Value of Bacterial Shape. Microbiol. Mol. Biol. Rev. 70: 660-703 [Abstract] [Full Text]  
  • Bettarel, Y., Bouvy, M., Dumont, C., Sime-Ngando, T. (2006). Virus-Bacterium Interactions in Water and Sediment of West African Inland Aquatic Systems. Appl. Environ. Microbiol. 72: 5274-5282 [Abstract] [Full Text]  
  • Colombet, J., Sime-Ngando, T., Cauchie, H. M., Fonty, G., Hoffmann, L., Demeure, G. (2006). Depth-related gradients of viral activity in lake pavin.. Appl. Environ. Microbiol. 72: 4440-4445 [Abstract] [Full Text]  
  • Corno, G., Jurgens, K. (2006). Direct and Indirect Effects of Protist Predation on Population Size Structure of a Bacterial Strain with High Phenotypic Plasticity. Appl. Environ. Microbiol. 72: 78-86 [Abstract] [Full Text]  
  • Tucker, S., Pollard, P. (2005). Identification of Cyanophage Ma-LBP and Infection of the Cyanobacterium Microcystis aeruginosa from an Australian Subtropical Lake by the Virus. Appl. Environ. Microbiol. 71: 629-635 [Abstract] [Full Text]  
  • Bettarel, Y., Sime-Ngando, T., Amblard, C., Dolan, J. (2004). Viral Activity in Two Contrasting Lake Ecosystems. Appl. Environ. Microbiol. 70: 2941-2951 [Abstract] [Full Text]  
  • Breitbart, M., Wegley, L., Leeds, S., Schoenfeld, T., Rohwer, F. (2004). Phage Community Dynamics in Hot Springs. Appl. Environ. Microbiol. 70: 1633-1640 [Abstract] [Full Text]  
  • Wolf, A., Wiese, J., Jost, G., Witzel, K.-P. (2003). Wide Geographic Distribution of Bacteriophages That Lyse the Same Indigenous Freshwater Isolate (Sphingomonas sp. Strain B18). Appl. Environ. Microbiol. 69: 2395-2398 [Abstract] [Full Text]  
  • Dominik, K., Hofle, M. G. (2002). Changes in Bacterioplankton Community Structure and Activity with Depth in a Eutrophic Lake as Revealed by 5S rRNA Analysis. Appl. Environ. Microbiol. 68: 3606-3613 [Abstract] [Full Text]  
  • Simek, K., Pernthaler, J., Weinbauer, M. G., Hornák, K., Dolan, J. R., Nedoma, J., Masín, M., Amann, R. (2001). Changes in Bacterial Community Composition and Dynamics and Viral Mortality Rates Associated with Enhanced Flagellate Grazing in a Mesoeutrophic Reservoir. Appl. Environ. Microbiol. 67: 2723-2733 [Abstract] [Full Text]  
  • Noble, R. T., Fuhrman, J. A. (2000). Rapid Virus Production and Removal as Measured with Fluorescently Labeled Viruses as Tracers. Appl. Environ. Microbiol. 66: 3790-3797 [Abstract] [Full Text]  
  • Jurgens, K., Jeppesen, E. (2000). The impact of metazooplankton on the structure of the microbial food web in a shallow, hypertrophic lake. J PLANKTON RES 22: 1047-1070 [Abstract] [Full Text]  
  • Wommack, K. E., Colwell, R. R. (2000). Virioplankton: Viruses in Aquatic Ecosystems. Microbiol. Mol. Biol. Rev. 64: 69-114 [Abstract] [Full Text]  
  • Guixa-Boixereu, N., Lysnes, K., Pedrós-Alió, C. (1999). Viral Lysis and Bacterivory during a Phytoplankton Bloom in a Coastal Water Microcosm. Appl. Environ. Microbiol. 65: 1949-1958 [Abstract] [Full Text]  
  • van Hannen, E. J., Zwart, G., van Agterveld, M. P., Gons, H. J., Ebert, J., Laanbroek, H. J. (1999). Changes in Bacterial and Eukaryotic Community Structure after Mass Lysis of Filamentous Cyanobacteria Associated with Viruses. Appl. Environ. Microbiol. 65: 795-801 [Abstract] [Full Text]  
  • Weinbauer, M. G., Höfle, M. G. (1998). Distribution and Life Strategies of Two Bacterial Populations in a Eutrophic Lake. Appl. Environ. Microbiol. 64: 3776-3783 [Abstract] [Full Text]