Validating models of bacterial chemotaxis by simulating the random motility coefficient

In order to characterize the random walk of E. coli, biologists have studied several parameters, such as the motility speed, run duration, and random motility coefficient. Previously, biologists indicated that the probability distributions of these parameters may vary depending on the presence or absence of a chemical gradient in the environment. For instance, in a gradient, the cell of E. coli exhibits a biased-random walk. Although it is suggested that the parameter distributions change from unbiased to biased conditions, there are contradicting reports of the actual distributions since they are usually derived from observations of cell movement. In this paper, we consider the problem conversely. We try hypotheses for the parameter distributions respectively for the unbiased and biased cases to simulate random walks. Then we can validate our chemotaxis model through the simulated random motility coefficient, under unbiased and biased environments.