Uncovering the coevolution between microbial predators and prey

Predation plays a key role in the planet’s ecology and evolution.

The most prevalent and diverse predators on the planet are protozoans, single-cell eukaryotes that live from consuming bacterial prey.

Protozoan predation massively impacts bacterial diversity, shapes microbial ecosystems, is essential for nutrient cycling and has been linked to the emergence of bacterial virulence. Yet, despite its importance, it remains largely elusive how protozoan predators and bacterial prey coevolve.

To understand this coevolution, we need an integrative research approach that accounts for offense and defense mechanisms in both predator and prey, and spans from cellular response systems to community ecology.Here, I take this approach, and present the first integrative research program on microbial predator-prey coevolution.

By leveraging recent advances in gene editing and single-cell phenotyping, we will focus on the coevolution between amoebal predators and bacterial prey in the soil – a hotspot for microbial predation. First, we will establish a predator-prey model system that permits a two-sided and systems-level analysis of predation.

Using genome-wide genetic screens, we will identify all genes underlying offense and defense mechanisms, study how they exert their effect, how they are regulated, and how they impact selection across environments. Second, we will expand from our model system, to study natural predator-prey soil communities.

We will explore how sexual reproduction and horizontal gene transfer impact coevolution, and emulate soil conditions in the lab, to determine how biotic and abiotic factors affect eco-evolutionary dynamics of predator-prey communities in both time and space.My research will connect ecology and evolution with molecular and systems biology, opening up the door for breakthrough advances in our understanding of predator-prey interfaces, the impact of coevolution on microbial ecosystems, and the emergence of nascent pathogenicity.