Social Dynamics, Signaling, and Surface Motility in Cyanobacteria: Integrating Models and Experiments

University Of Maryland, College Park, College Park MD

Investigators

Abstract

Microorganisms live in environments that are often severely limited in resources or in which vital inputs such as light and nutrients fluctuate unpredictably. Thus, their ability to sense and respond quickly to environmental cues is finely regulated and well-evolved. We are particularly interested in the exquisite ability of photosynthetic microorganisms, like cyanobacteria, to sense and respond to light, in a process called phototaxis. Based on our preliminary studies, we hypothesize that the motility of cyanobacteria in space and time is a result of an intricate interplay between the characteristics of an individual bacterium and the social dynamics of the colony. We aim (1) To experimentally monitor surface dependent motility of Synechocystis sp. under defined, biologically relevant conditions. (2) To derive, study, and test mathematical models that will be integrated with the new biological data. (3) To use phototaxis mutants to extend and refine mathematical models in the context of biologically relevant questions. This project deals with fundamental biological questions about cell motility and social behavior. A successful completion of the proposed activities will shed light on how single cells perceive light signals and the importance of communication for social behaviors that lead to group movement. The project is designed as a truly interdisciplinary effort to deal with a complex phenomenon. It extends the promising preliminary results of the work of the investigators bringing together math and biology. A considerable intellectual effort is embedded in designing the mathematical research directions that will provide answers that are relevant to solving biological problems. This project potentially has a direct impact on fundamental biological questions in other fields. The widespread importance of mixed bacterial communities and surface dependent motility is becoming increasingly apparent in the field of pathogen biology as well as in environmental microbial ecology. Mathematical models that directly address group dynamics could be potentially very relevant to other problems: biological (such as modeling the behavior of ant colonies), and non-biological (such as crowds behavior in models in economics and social networks). The project includes a substantial educational component that reflects an ongoing commitment to education on all levels (undergraduate, graduate, and post-graduate education). Special attention is given to outreach activities, minorities, and to developing programs that foster and encourage training in the fields of biology and mathematics.