Bacterial morphogenesis and growth control in dynamic environments

Bacteria are highly adaptive microorganisms that thrive in a wide range of environmental conditions via changes in cell morphologies and macromolecular composition. How bacterial growth and morphologies are regulated in diverse environmental conditions is a long-standing question. Regulation of bacterial cell size implies cellular control mechanisms that couple bacterial growth and division to the extracellular environment and intracellular composition. In the past decade, simple quantitative laws have emerged that connect cell growth to proteomic composition and the nutrient availability in the external environment. However, the relationships between cell morphology and growth physiology remain poorly understood in dynamic environments. In this talk, I will present our recent work on understanding the physical and biological forces that regulate bacterial growth and morphological adaptation in dynamic changing environments. Specifically, I'll discuss how changes in nutrient environments modulate cell shape, growth, and mechanics to optimize cellular adaptive performance under stress. Integrating quantitative theories with experimental data, we identify mechanistic models underlying cellular growth control and shape regulation, revealing the intimate connections between cell morphology and organismal fitness. In particular, we show how shape changes can provide adaptive benefits in stressful environments.