A Multi-Scale Approach to Modeling E. coli Chemotaxis

Modeling E. coli Tumbles by Rotational Diffusion. Implications for Chemotaxis

The bacterium Escherichia coli in suspension in a liquid medium swims by a succession of runs and tumbles, effectively describing a random walk. The tumbles randomize incompletely, i.e. with a directional persistence, the orientation taken by the bacterium. Here, we model these tumbles by an active rotational diffusion process characterized by a diffusion coefficient and a diffusion time. In ho...

Engineered single- and multi-cell chemotaxis pathways in E. coli

We have engineered the chemotaxis system of Escherichia coli to respond to molecules that are not attractants for wild-type cells. The system depends on an artificially introduced enzymatic activity that converts the target molecule into a ligand for an E. coli chemoreceptor, thereby enabling the cells to respond to the new attractant. Two systems were designed, and both showed robust chemotact...

A GIS-based multi-scale approach to habitat suitability modeling

The aim of this study is to develop a method by means of which it is possible to produce georeferenced ecological information about the habitat requirements of different species. The integrated habitat suitability index approach includes the steps of constructing habitat suitability models, producing data needed in models, evaluating of target areas based on habitat factors, and combining vario...

Optimal search in E. coli chemotaxis.

We study chemotaxis of a single E. coli bacterium in a medium where the nutrient chemical is also undergoing diffusion and its concentration has the form of a Gaussian whose width increases with time. We measure the average first passage time of the bacterium at a region of high nutrient concentration. In the limit of very slow nutrient diffusion, the bacterium effectively experiences a Gaussia...

VRIJE UNIVERSITEIT A Computational Study of E. coli Chemotaxis