Run-and-Tumble Analysis of Enterobacter Sp. SM3

We present first findings of the run-and-tumble behavior of the newly-discovered, swarm-competent bacterium enterobacter sp. SM3. SM3 has been shown to reduce stomach lining inflammation in mice afflicted with irritable bowel disease (De et al., Gastroenterology, 2021) and it offers a new opportunity to elucidate the physical mechanism of swarming motility. To better understand the swarming motility of SM3, and thereby gain insight into the connection between swarming and inflammation, it is a useful initial step to measure SM3 in its state as individual swimmers. Here we demonstrate how relevant run-and-tumble behavior, characterized by physical parameters such as the tumble time, run time, and tumble angle, vary with factors including exposure to various chemicals and whether SM3 is taken from a swarm prior to its release in an aqueous environment. These results are compared to those of E. coli to determine the extent to which they share run-and-tumble type swimming behavior. Our data also serve as a benchmark for understanding the connection between swimming and swarming motility.