Characterization of Vibrio cholerae Motility Using High-Throughput 3D Tracking

Abstract

Motility is known to contribute to pathogenicity in many bacterial species, but the underlying mechanisms are mostly unknown. We strive to characterize motility behavior in Vibrio cholerae, the causative agent of cholera, and identify adaptations relevant to pathogenicity. Here we present a quantitative characterization of V. cholerae motility in liquids using a recent high-throughput 3D tracking method, enabling a more comprehensive analysis of motility behavior. We typically acquired more than 5,000 individual 3D trajectories in 10 minutes. After an experimental protocol was developed that yielded a motile fraction greater than 90% and population-averaged swimming speeds greater than 90 µm/s and analysis program optimized with a false positive and negative detection rate of only 3-4%, we demonstrated for the first time that V. cholerae exhibits run-reverse-flick motility in liquids, and quantified population distributions of turning angles, swimming speed, and run durations. We also characterized another novel behavioral feature: deceleration events during runs. Our findings provide a baseline for studies of V. cholerae motility in complex environments more closely mimicking the host as well as chemotaxis assays. An understanding of V. cholerae navigation strategies could provide insight into the early stages of infection.