Adjustment in tumbling rates improves bacterial chemotaxis on obstacle-laden terrains

Abstract

Significance Bacterial chemotaxis is the process of bacterial migration in the direction of food and/or a chemoattractant and away from chemorepellents. Several models have been proposed for this process and these predict that their migration across obstacle-laden terrains would be slower when compared with terrains that do not contain obstacles. However, our experiments show that the presence of obstacles does not alter the average time it takes Escherichia coli cells to reach the food source. We show, both theoretically and experimentally, that a modified model that relies on adaptive movement following collisions with obstacles accurately explains this surprising result. These findings imply operational short-term memory of bacteria and motivate improved algorithms for self-autonomous robotic swarms.