Bacteriophage Ecology
Our lab is interested in how phage replication strategies shape the microbiome of animal hosts and modulate the interplay between commensal and pathogenic microbes. During lytic infections, phages take over the bacterial cell machinery to produce viral particles released upon lysis. During lysogeny, phages integrate into the bacterial chromosome, and are duplicated along the cell genetic material at every replication event. These two strategies have divergent outcomes: bacterial top-down control by lytic viral infection, and increased bacterial fitness and resistance by lysogeny. The underlying hypothesis of this research program is that microbial communities associated with animal hosts are predominantly lysogenic, and that integrated prophages confer higher fitness to the resident community compared to foreign microbes.
Phage roles in coral health and disease
Lateral transfer of virulence genes by phages is a major mechanism for the rise of pathogens. This research investigates virulence genes encoded by temperate phages and their effect on bacterial interaction with corals. The outcomes of phage-mediated gene transfers are often community dominance by virulent strains and the generation of evolutionary ratchets of bacteria-phage cooperation. This work utilizes bioinformatics approaches to identify patterns in virulence gene distributions and mutation rates in coral reefs, followed by infection experiments and cellular biology tools to access the effect of phage gene products on coral health.
Lateral transfer of virulence genes by phages is a major mechanism for the rise of pathogens. This research investigates virulence genes encoded by temperate phages and their effect on bacterial interaction with corals. The outcomes of phage-mediated gene transfers are often community dominance by virulent strains and the generation of evolutionary ratchets of bacteria-phage cooperation. This work utilizes bioinformatics approaches to identify patterns in virulence gene distributions and mutation rates in coral reefs, followed by infection experiments and cellular biology tools to access the effect of phage gene products on coral health.
Molecular drivers of phage infection strategies
The canonical view on the prevalence of lysogeny in the environment comes from the interaction of the model organisms E. coli and lambda phage. However, the assumption that mixed communities in natural environments reproduce the E. coli model are overly simplistic. On coral reefs, rewiring of central carbon pathways by heterotrophic bacteria during coral reef trophic downgrading yield metabolic scenarios favoring lysogeny. This research employs in situ and in vitro incubation experiments to analyze bacterial metabolism, followed by bioinformatics and mathematical models to predict the ecological scenarios favoring lysogeny. This work offers a new viewpoint on lysogeny and its outcomes in complex microbial communities.
The canonical view on the prevalence of lysogeny in the environment comes from the interaction of the model organisms E. coli and lambda phage. However, the assumption that mixed communities in natural environments reproduce the E. coli model are overly simplistic. On coral reefs, rewiring of central carbon pathways by heterotrophic bacteria during coral reef trophic downgrading yield metabolic scenarios favoring lysogeny. This research employs in situ and in vitro incubation experiments to analyze bacterial metabolism, followed by bioinformatics and mathematical models to predict the ecological scenarios favoring lysogeny. This work offers a new viewpoint on lysogeny and its outcomes in complex microbial communities.
Tripartite phage-bacteria-coral symbiosis
This research program focuses on the role of lysogeny in the establishment, function, and stability of microbial communities associated with corals. Most phages associated with animals, from corals to humans, are temperate, suggesting that lysogeny plays a central role in the community assembly of animal microbiomes. Lysogeny can create a self-recognition mechanism through superinfection exclusion, and manipulate bacterial function through lateral gene transfer. Scleractinian corals are ideal models for this research because of their position as basal metazonas harboring complex innate immune system and mucosal layers. The main goal of this research is to identify fundamental rules governing the association between phages and animal microbiomes. |