E 7 - Knut Drescher

Environmental triggers for dispersal of Vibrio cholerae biofilms








Prof. Dr. Knut Drescher

SYNMIKRO & Max Planck Institute for Terrestrial Microbiology

Karl-von-Frisch-Straße 16, 35043 Marburg

+49 - 6421 - 2821473




Research summary:

By growing in matrix-enclosed groups, which are known as biofilms, bacteria can become immune to a large variety of environmental stresses. The typical life cycle of a biofilm includes cell-to-surface attachment, immobilization, extracellular matrix secretion, growth into multicellular cell clusters, and finally dispersal back into the surrounding environment. Though all phases of this cycle are critical to understanding biofilm behavior, they have not been given equal attention; in particular, little is known about the environmental triggers, signals, precise mechanisms, matrix architectural modifications, and evolutionary fitness consequences of dispersal. To fill this gap, we will use a combination of methods from molecular biology and physics to study the dispersal of individual cells from Vibrio cholerae biofilms, and the en mass dispersal of a large fraction of the cells inside a biofilm.

Firstly, we aim to determine the spatiotemporal dynamics of biofilm dispersal at single-cell resolution, using novel microscopy and image analysis technology developed in my group. Secondly, we will uncover the detailed relationship between quorum sensing and dispersal – our preliminary results suggest that quorum sensing is involved in triggering biofilm mass dispersal. Thirdly, we will use custom microfluidics to capture dispersing cells and measure their transcriptomic and metabolomic profiles, to determine the general regulatory mechanisms underlying dispersal events. In our fourth aim, we will investigate the structural and compositional changes of the biofilm matrix during biofilm dispersal. Lastly, we will determine how the physical and environmental conditions, such as flow profiles and substrata topography found in the natural environments of V. cholerae impinge on the accumulation of signals that eventually trigger biofilm dispersal. At all points during the proposed work, we will assess whether the regulatory mechanisms that control the dispersal of individual cells and those that control mass dispersal events are fundamentally different.