ABSTRACT

The gut microbiota plays a critical role in host health, and quantifying the kinetics of bacterial colonization, replication, and death is essential for understanding gut population dynamics. However, accurately estimating the rates of these processes remains challenging due to population heterogeneity arising from rare stochastic events, resulting in disparate population sizes spanning multiple orders of magnitude.

To explore this issue, we investigated Escherichia coli population dynamics within the gut of Caenorhabditis elegans. We examined gut bacterial populations at multiple timepoints following different bacterial diets, which were designed to modulate different dynamics. Individual nematodes were homogenized and plated for colony-forming unit (CFU) enumeration, from which population numbers were reconstructed. This data was analyzed using stochastic simulations combined with Bayesian methods to estimate distributions of kinetic rates. This framework was subsequently applied to quantify the impact of bacterial predation on gut population dynamics.

BIOSKETCH

Dr. Stanimir Asenov Tashev is a Postdoctoral Researcher at the Center for Biological Physics at Arizona State University. Originally from Bulgaria, he moved to the United Kingdom, where he earned a BSc in Biomedical Sciences from the University of Southampton, followed by a PhD from the University of Birmingham. His doctoral research focused on developing quantitative methods for counting proteins within resolution-limited clusters. His current work investigates bacterial population dynamics in spatially constrained environments, with a particular emphasis on quantitative modeling and advanced microscopy techniques. Ultimately, his research aims to understand how geometrically complex environments shape interactions between bacterial predators and their prey.