Eco-evolutionary dynamics of microbial populations with heterogeneous growth and dispersal

Speaker: Ashish Bino George, Boston University, Physics Department

When: April 6, 2020 (Mon), 02:30PM to 03:30PM (add to my calendar)

This event is part of the Departmental Seminars.

Understanding eco-evolutionary dynamics in bacterial colonies, cancer tumors, and the human microbiome is vital for many health, energy, and agricultural applications. However, spatial structure and population heterogeneity make this challenging. My research examines the evolutionary consequences of cell shape asymmetry and phenotypic heterogeneity in spatially expanding populations.

First, I examine the evolutionary effect of chiral cell shape in bacterial, human, and cancer cells. I will present a minimal model of chiral growth that quantitatively reproduces experimental patterns in bacterial colonies. The model shows that cells can invade by either increasing their chirality or switching their handedness. To understand how chirality mediates competition, we derived a general effective theory of chiral growth. The theory reveals that selection occurs due to coupling of the dynamics of the expanding colony edge and the population dynamics at the edge.

Second, I describe a growing bacterial colony, composed of phenotypes with distinct growth and migration strategies. I show that coordinated phenotypic switching in a cooperative population reproduces periodic, pulsed expansions observed in P. mirabilis colonies, and discuss implied evolutionary tradeoffs. I conclude by presenting ongoing work on the assembly of complex microbial communities optimized to perform a specific function like producing biofuel or treating disease. I will describe a framework for community optimization and methods to help bioengineers estimate the difficulty of searching for an optimal community.

Join Zoom Meeting

Meeting ID: 433 892 652