Ecological and Evolutionary Science
Research Article | Ecological and Evolutionary ScienceResistance Evolution against Phage Combinations Depends on the Timing and Order of ExposureGlobally rising rates of antibiotic resistance have renewed interest in phage therapy where combinations of phages have been successfully used to treat multidrug-resistant infections. To optimize phage therapy, we first need to understand how bacteria evolve resistance against combinations of multiple phages. Here, we use simple laboratory experiments and genome sequencing to show that the timing and order of phage exposure determine...
Perspective | Ecological and Evolutionary ScienceAntibiotics: Combatting Tolerance To Stop ResistanceAntibiotic resistance poses an alarming and ever-increasing threat to modern health care. Although the current antibiotic crisis is widely acknowledged, actions taken so far have proved insufficient to slow down the rampant spread of resistant pathogens. Problematically, routine screening methods and strategies to restrict therapy failure almost exclusively focus on genetic resistance, while evidence for dangers posed by other bacterial...
Research Article | Ecological and Evolutionary ScienceMetagenomes from Coastal Marine Sediments Give Insights into the Ecological Role and Cellular Features of Loki- and ThorarchaeotaMicroorganisms of the superphylum Asgard Archaea are considered to be the closest living prokaryotic relatives of eukaryotes (including plants and animals) and thus promise to give insights into the early evolution of more complex life forms. However, very little is known about their biology as none of the organisms has yet been cultivated in the laboratory. Here we report on the ecological distribution of Asgard Archaea...
Research Article | Ecological and Evolutionary ScienceTransposon-Mediated Horizontal Transfer of the Host-Specific Virulence Protein ToxA between Three Fungal Wheat PathogensThis work dissects the tripartite horizontal transfer of ToxA, a gene that has a direct negative impact on global wheat yields. Defining the extent of horizontally transferred DNA is important because it can provide clues to the mechanisms that facilitate HGT. Our analysis of ToxA and its surrounding 14 kb suggests that this gene was horizontally transferred in two independent events, with one event likely facilitated...
Research Article | Ecological and Evolutionary ScienceMassive Gene Flux Drives Genome Diversity between Sympatric Streptomyces ConspecificsHorizontal gene transfer is a rapid and efficient way to diversify bacterial gene pools. Currently, little is known about this gene flux within natural soil populations. Using comparative genomics of Streptomyces strains belonging to the same species and isolated at microscale, we reveal frequent transfer of a significant fraction of the pangenome. We show that it occurs at a time scale enabling the population to diversify and...
Research Article | Ecological and Evolutionary ScienceThe Origin, Succession, and Predicted Metabolism of Bacterial Communities Associated with Leaf DecompositionCommunity ecologists have traditionally treated individuals within a species as uniform, with individual-level biodiversity rarely considered as a regulator of community and ecosystem function. In our study system, we have documented clear evidence of within-species variation causing local ecosystem adaptation to fluxes across ecosystem boundaries. In this striking pattern of a “home-field advantage,” leaves from individual trees tend...
Research Article | Ecological and Evolutionary ScienceSystems Biology and Pangenome of Salmonella O-AntigensLipopolysaccharides are a major component of the outer membrane in Gram-negative bacteria. They are composed of a conserved lipid structure that is embedded in the outer leaflet of the outer membrane and a polysaccharide known as the O-antigen. O-antigens are highly variable in structure across strains of a species and are crucial to a bacterium’s interactions with its environment. They constitute the first line of defense against both...
Research Article | Ecological and Evolutionary ScienceA Membrane-Bound Cytochrome Enables Methanosarcina acetivorans To Conserve Energy from Extracellular Electron TransferThe discovery of a methanogen that can conserve energy to support growth solely from the oxidation of organic carbon coupled to the reduction of an extracellular electron acceptor expands the possible environments in which methanogens might thrive. The potential importance of c-type cytochromes for extracellular electron transfer to syntrophic bacterial partners and/or Fe(III) minerals in some Archaea was previously...
Editor's Pick Research Article | Ecological and Evolutionary SciencePseudomonas aeruginosa Interstrain Dynamics and Selection of Hyperbiofilm Mutants during a Chronic InfectionBacteria adapt to infections by evolving variants that are more fit and persistent. These recalcitrant variants are typically observed in chronic infections. However, it is unclear when and why these variants evolve. To address these questions, we used a porcine chronic wound model to study the evolutionary dynamics of Pseudomonas aeruginosa in a mixed-strain...
Research Article | Ecological and Evolutionary ScienceMicrobial Similarity between Students in a Common Dormitory Environment Reveals the Forensic Potential of Individual Microbial SignaturesHumans leave behind a microbial trail, regardless of intention. This may allow for the identification of individuals based on the “microbial signatures” they shed in built environments. In a shared living environment, these trails intersect, and through interaction with common surfaces may become homogenized, potentially confounding our ability to link individuals to their associated microbiota. We sought to understand the factors that...