10.5061/DRYAD.MR0N8
Zhang, Ji
University of Helsinki
University of Jyväskylä
Örmälä-Odegrip, Anni-Maria
University of Helsinki
University of Jyväskylä
Mappes, Johanna
University of Jyväskylä
Laakso, Jouni
University of Helsinki
University of Jyväskylä
Data from: Top-down effects of a lytic bacteriophage and protozoa on
bacteria in aqueous and biofilm phases
Dryad
dataset
2015
2015-10-02T00:00:00Z
2015-10-02T00:00:00Z
en
https://doi.org/10.1002/ece3.1302
113811 bytes
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CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Lytic bacteriophages and protozoan predators are the major causes of
bacterial mortality in natural microbial communities, which also makes
them potential candidates for biological control of bacterial pathogens.
However, little is known about the relative impact of bacteriophages and
protozoa on the dynamics of bacterial biomass in aqueous and biofilm
phases. Here, we studied the temporal and spatial dynamics of bacterial
biomass in a microcosm experiment where opportunistic pathogenic bacteria
Serratia marcescens was exposed to particle-feeding ciliates,
surface-feeding amoebas, and lytic bacteriophages for 8 weeks, ca. 1300
generations. We found that ciliates were the most efficient enemy type in
reducing bacterial biomass in the open water, but least efficient in
reducing the biofilm biomass. Biofilm was rather resistant against
bacterivores, but amoebae had a significant long-term negative effect on
bacterial biomass both in the open-water phase and biofilm. Bacteriophages
had only a minor long-term effect on bacterial biomass in open-water and
biofilm phases. However, separate short-term experiments with the
ancestral bacteriophages and bacteria revealed that bacteriophages crash
the bacterial biomass dramatically in the open-water phase within the
first 24 h. Thereafter, the bacteria evolve phage-resistance that largely
prevents top-down effects. The combination of all three enemy types was
most effective in reducing biofilm biomass, whereas in the open-water
phase the ciliates dominated the trophic effects. Our results highlight
the importance of enemy feeding mode on determining the spatial
distribution and abundance of bacterial biomass. Moreover, the enemy type
can be crucially important predictor of whether the rapid defense
evolution can significantly affect top-down regulation of bacteria.
Biomass dynamics in free water and biofilmAmoeba and ciliate dynamics