Fluid Flow as a Driver of Bacterial Cell Division, Surface Motility, and Spreading

Princeton University, Princeton NJ

Investigators

Abstract

This project combines expertises in microbiology, engineering, and physics to advance understanding of how fluid flow affects bacterial shape, motility and spreading. There are many factors that account for the abundance of bacteria. For example, bacteria are found with different morphologies and each species has a specific characteristic shape, suggesting that shape is under intense selective pressure. Therefore, understanding the physiological benefits of specific shapes is a fundamental question in basic biology. In addition, bacteria have evolved a number of motility mechanisms that enable movement in liquid environments and on solid surfaces. While flagellar-driven swimming in liquid environments has been characterized extensively, far less is known about surface motility, and even less is known about the influence of flow on establishing unique microbial surface, or near-surface, responses. Finally, the major determinants of the fitness of bacterial populations in nature are their ability to grow/divide in their current environment and their ability to spread into new environments capable of supporting their growth. Little is known about how bacteria spread in the presence of flow. Each of these themes is addressed in this project by integrating the experimental tools of molecular biology with the experimental and theoretical perspectives of engineering and physics. In particular, this work will (i) study how flow differentially impacts the division of bacteria with different shapes, (ii) investigate the effect of fluid flow on bacterial surface motility and study the role of fluid flow in affecting bacterial spreading for both (iii) near-surface planktonic cells and (iv) surface-attached populations. The broader impact of this research will include the PIs publishing in leading journals across molecular biology, biophysics, engineering, and physics, hosting visitors from different disciplines and institutions, engaging undergraduate students in research, giving talks at conferences, leading professional development activities for undergraduate, graduate, and postdoctoral colleagues, and participating in research programs oriented towards young researchers from under-represented groups. Also, the PIs have successfully incorporated research themes into outreach activities aimed at young people such as lectures and activities for secondary school students and "holiday" lectures for children and parents. The outreach activities are directly linked to the project and reflect the PIs commitment to being engaged in teaching and mentoring future research scientists.