Abstract
Bacterial cells' behavior in which they accumulate around a source of chemical attractant was modeled as a biased discrete random walk. In this model, a model cell straightly moves during a certain period with a determined speed. After the motion, the model cell changes its direction in a random choice. Then, the model cell again moves in the determined direction. A parameter a was introduced to include biased effect in the model. When a model cell approached the chemical source in the previous step, the cell will continue to move in the same direction with the probability α, or the cell randomly change its direction with the probability (1-α). Numerical simulations for the motion in 2D plane were performed. They revealed that the distribution of the model cell is like an exponential distribution with an index related to α. This indicates the potential of this model to express the strength of bacterial chemo-taxis in terms of α.
