Determining the minimal nutrient requirements for the swarming phenotype in Escherichia coli and other swarming bacterial species

Abstract

This project lays the foundation for identifying chemical inducers and inhibitors in swarming cells of Escherichia coli. Swarming is a type of cell surface motility characterized by differentiated bacterial cells that have an elongated, hyper-flagellated, and multinucleated phenotype. This swarmer cell phenotype is thought to be the prevalent phenotype in the infection of urinary tracts and bladders by uropathogenic strains of Escherichia coli and Proteus mirabilis. The nutritional requirements necessary for differentiation and swarming motility are poorly understood. The goal of this project was to formulate and characterize nutrient media that has a well-defined set of components necessary to produce a robust swarming phenotype. This minimal swarm media was designed to satisfy the following characteristics: (1) chemical reproducibility, (2) defined composition, (3) production of the swarming, hyper-flagellated phenotype in E. coli and other swarming bacteria, (4) induction of surface motility, and (5) lack of auto-fluorescence. We suggest that the designed media could serve to standardize the swarming field of study and could provide a reproducibly defined platform on which to perform future examination of the swarming phenotype.