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Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
Induction of prophages from deep-subseafloor bacteria
Tim Engelhardt1, Monika Sahlberg, Heribert Cypionka
1Carl-von-Ossietzky Universität Oldenburg, Institut für Chemie und Biologie des Meeres, Carl-von-Ossietzky Straße 9-11, D-26129 Oldenburg, Germany.
Environmental Microbiology Reports
|June 14, 2013
Summary
This study reveals functional viruses in the deep-subseafloor biosphere, with bacteriophages potentially regulating microbial populations and recycling nutrients in this extreme environment.
Area of Science:
- Microbiology
- Marine Biology
- Geobiology
Background:
- The deep-subseafloor biosphere contains significant microbial biomass.
- Regulation of life and death in this environment remains poorly understood.
- Viruses are potential mortality factors for microbes in the absence of higher trophic levels.
Purpose of the Study:
- To investigate the presence and activity of viruses in the deep-subseafloor biosphere.
- To determine the role of viruses as mortality factors and in nutrient cycling.
Main Methods:
- Analysis of viral to cell count ratios with sediment depth.
- Induction of prophages in bacterial isolates using mitomycin C.
- Detection and characterization of viruses using transmission electron microscopy and pulsed-field gel electrophoresis.
Main Results:
- Viral to cell counts increased with depth in subseafloor sediments.
- Prophages were inducible in 46% of bacterial isolates.
- Diverse bacteriophages (myoviruses, siphoviruses) were detected, exhibiting genetic diversity.
Conclusions:
- Functional viruses, specifically bacteriophages, exist in the deep-subseafloor biosphere.
- Bacteriophages may act as primary predators in this anoxic, oligotrophic habitat.
- The viral shunt likely plays a crucial role in nutrient recycling in this nutrient-limited environment.
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