Adaptive cell-cell communication enhances bacterial chemotaxis

Bacteria track chemical gradients using a biased random walk, a process called chemotaxis. Recent experiments suggest that bacteria also communicate during this process. Using mathematical modeling and computer simulation, we find that sufficiently strong communication succeeds in keeping a population of bacteria together, but actually slows down chemotaxis. However, if communication strength is adapted to the level of the external chemical, we find that chemotaxis is instead sped up. We apply our findings to E. coli, where both communication and cell-to-cell variability play an important role. Using experimental data to calibrate the model, we predict that adaptive communication and cell-to-cell variability can synergistically increase chemotaxis speed.