10 research outputs found
Predator-by-Environment Interactions Mediate Bacterial Competition in the \u3ci\u3eDictyostelium discoideum\u3c/i\u3e Microbiome
Interactions between species and their environment play a key role in the evolution of diverse communities, and numerous studies have emphasized that interactions among microbes and among trophic levels play an important role in maintaining microbial diversity and ecosystem functioning. In this study, we investigate how two of these types of interactions, public goods cooperation through the production of iron scavenging siderophores and predation by the social amoeba Dictyostelium discoideum, mediate competition between two strains of Pseudomonas fluorescens that were co-isolated from D. discoideum. We find that although we are able to generally predict the competitive outcomes between strains based on the presence and absence of either D. discoideum or iron, predator-by-environment interactions result in unexpected competitive outcomes. This suggests that while both cooperation and predation can mediate the competitive abilities and potentially the coexistence of these strains, predicting how combinations of different environments affect even the relatively simple microbiome of D. discoideum remains challenging
Hey! That\u27s Cheating: Cooperatin within Pseudomonas fluorescens
From the Washington University Undergraduate Research Digest: WUURD, Volume 11, 2015-2016. Published by the Office of Undergraduate Research, Joy Zalis Kiefer Director of Undergraduate Research and Assistant Dean in the College of Arts & Sciences; Lindsey Paunovich, Editor; Kristin Sobotka, Editor; Jennifer Kohl.
Mentor: David Queller and Joan Strassman
Hey! That\u27s Cheating: Cooperation within Pseudomonas fluorescens
From the Washington University Undergraduate Research Digest: WUURD, Volume 10, 2014-2015. Published by the Office of Undergraduate Research, Joy Zalis Kiefer Director of Undergraduate Research and Assistant Dean in the College of Arts & Sciences; Stacy Ross, Editor; Kristin Sobotka, Editor; Jennifer Kohl. Mentor: Joan Strassman
Data from: Does high relatedness promote cheater-free multicellularity in synthetic lifecycles?
The evolution of multicellularity is one of the key transitions in evolution and requires extreme levels of cooperation between cells. However, even when cells are genetically identical, non-cooperative cheating mutants can arise that cause a breakdown in cooperation. How then, do multicellular organisms maintain cooperation between cells? A number of mechanisms that increase relatedness amongst cooperative cells have been implicated in the maintenance of cooperative multicellularity including single cell bottlenecks and kin recognition. In this study we explore how relatively simple biological processes such as growth and dispersal can act to increase relatedness and promote multicellular cooperation. Using experimental populations of pseudo-organisms, we found that manipulating growth and dispersal of clones of a social amoeba to create high levels of relatedness was sufficient to prevent the spread of cheating mutants. By contrast cheaters were able to spread under low relatedness conditions. Most surprisingly, we saw the largest increase in cheating mutants under an experimental treatment that should create intermediate levels of relatedness. This is because one of the factors raising relatedness, structured growth, also causes high vulnerability to growth rate cheaters
Predator-By-Environment Interactions Mediate Bacterial Competition in the Dictyostelium Discoideum Microbiome
Interactions between species and their environment play a key role in the evolution of diverse communities, and numerous studies have emphasized that interactions among microbes and among trophic levels play an important role in maintaining microbial diversity and ecosystem functioning. In this study, we investigate how two of these types of interactions, public goods cooperation through the production of iron scavenging siderophores and predation by the social amoeba Dictyostelium discoideum, mediate competition between two strains of Pseudomonas fluorescens that were co-isolated from D. discoideum. We find that although we are able to generally predict the competitive outcomes between strains based on the presence and absence of either D. discoideum or iron, predator-by-environment interactions result in unexpected competitive outcomes. This suggests that while both cooperation and predation can mediate the competitive abilities and potentially the coexistence of these strains, predicting how combinations of different environments affect even the relatively simple microbiome of D. discoideum remains challenging
Predator-by-Environment Interactions Mediate Bacterial Competition in the Dictyostelium discoideum Microbiome
Interactions between species and their environment play a key role in the evolution of diverse communities, and numerous studies have emphasized that interactions among microbes and among trophic levels play an important role in maintaining microbial diversity and ecosystem functioning. In this study, we investigate how two of these types of interactions, public goods cooperation through the production of iron scavenging siderophores and predation by the social amoeba Dictyostelium discoideum, mediate competition between two strains of Pseudomonas fluorescens that were co-isolated from D. discoideum. We find that although we are able to generally predict the competitive outcomes between strains based on the presence and absence of either D. discoideum or iron, predator-by-environment interactions result in unexpected competitive outcomes. This suggests that while both cooperation and predation can mediate the competitive abilities and potentially the coexistence of these strains, predicting how combinations of different environments affect even the relatively simple microbiome of D. discoideum remains challenging
Expansion rate
Comparison of the expansion rates across a nutrient agar plate of NC28.1 and EC28.2
Flow cytometry results
Cells counts of fluorescently-labelled and non-labelled D. discoideum spores, that underwent varying levels of structured growth and structured dispersa
Growth Rates
Comparison of growth rates between EC28.2 and NC28.2
Data_Sheet_1_Predator-by-Environment Interactions Mediate Bacterial Competition in the Dictyostelium discoideum Microbiome.DOCX
<p>Interactions between species and their environment play a key role in the evolution of diverse communities, and numerous studies have emphasized that interactions among microbes and among trophic levels play an important role in maintaining microbial diversity and ecosystem functioning. In this study, we investigate how two of these types of interactions, public goods cooperation through the production of iron scavenging siderophores and predation by the social amoeba Dictyostelium discoideum, mediate competition between two strains of Pseudomonas fluorescens that were co-isolated from D. discoideum. We find that although we are able to generally predict the competitive outcomes between strains based on the presence and absence of either D. discoideum or iron, predator-by-environment interactions result in unexpected competitive outcomes. This suggests that while both cooperation and predation can mediate the competitive abilities and potentially the coexistence of these strains, predicting how combinations of different environments affect even the relatively simple microbiome of D. discoideum remains challenging.</p