E. coli in Motion

  title={E. coli in Motion},
  author={Louis J. DeFelice},
  booktitle={Biological and Medical Physics, Biomedical Engineering},

Swimming behavior of the monotrichous bacterium Pseudomonas fluorescens SBW25.

The flagellation and swimming behavior of P. fluorescens SBW25 show some similarity to Caulobacter, a fresh-water inhabitant, while the complex swimming pattern might be an adaptation to the geometrically restricted rhizo- and phyllospheres.

Survival in a Sea of Gradients: Bacterial and Archaeal Foraging in a Heterogeneous Ocean

The physical and biological processes that structure the ocean at the scale of marine microbes, the adaptations enabling them to navigate this patchy seascape, and the way these microscale behaviors can scale-up to influence large-scale biogeochemical processes are described.

Optimal search strategies and intermittent random walk : from restriction enzymes to the albatross flight

This thesis deals with intermittent target search strategies, which combine slow phases, allowing the searcher to detect the target, and fast phases without detection. Foraging animals are an example

Bacterial Proprioception: Can a Bacterium Sense Its Movement?

The mechanism whereby the flagellar motor precisely tunes its chemotaxis output under different mechanical loads, analogous to proprioception in higher order organisms, is discussed and speculated on the roles bacterial proprioceptions might play in a variety of phenomena including the transition to surface-associated lifestyles such as swarming and biofilms.

Spatial modulation of individual behaviors enables an ordered structure of diverse phenotypes during bacterial group migration

By investigating the single-cell trajectories during group migration, it is discovered that, despite the constant migrating speed of a group, the drift velocities of individual bacteria decrease from the back to the front, which implies the spatial modulation of individual run-and-tumble random motions and enables the bacterial population to migrate as a pushed wave front.

Hydrodynamics and direction change of tumbling bacteria

A theoretical approach to model the angular distribution of swimming E. coli cells during tumbles finds that the main change of direction occurs during the ‘bundling’ part of the process wherein, at the end of a tumble, the dispersed flagellar filaments are brought back together in the helical bundle, which is confirmed using a simplified forced-sphere model.

A model of strongly biased chemotaxis reveals the trade-offs of different bacterial migration strategies.

A model for strong chemotaxis is derived that resolves how both the drift and diffusive components depend on the underlying chemotactic strategy and is tested against individual-based simulations and identifies further refinements that allow the continuum model to resolve boundary effects.

Bacterial flagellar motor

This review outlines what has been learned about the structure and function of the bacterial flagellar motor using a combination of genetics, single-molecule and biophysical techniques, with a focus on recent results and single-Molecule techniques.

Deep learning in light–matter interactions

The emerging opportunities and challenges of deep learning in photonics are discussed, shining light on how deep learning advances photonics.



Random Walks in Biology

This book is a lucid, straightforward introduction to the concepts and techniques of statistical physics that students of biology, biochemistry, and biophysics must know. It provides a sound basis

Über die Sichtbarmachung der Geisseln und die Geisselbewegung der Bakterien

  • Zentralbl. Bakteriol. Parasitenk. Infektionskr. Abt. 1 Orig. 51:14–94.
  • 1909

Flagellar rotation and the mechanism of bacterial motility

BACTERIAL flagella are generally composed of three morphologically distinguishable regions: the long flagellar filament, the hook, and the basal structure which is composed of an intricate set of disks and rods attaching the hook to the cell membrane and cell wall.

Flagella and motility

Targeted disulfide cross-linking of the MotB protein of Escherichia coli: evidence for two H(+) channels in the stator Complex.

A targeted disulfide-cross-linking study is begun to probe the arrangement of membrane segments in the MotA/MotB complex, beginning with the single membrane segment of MotB.

Function of Proline Residues of MotA in Torque Generation by the Flagellar Motor of Escherichia coli

Motor function in Pro 173 and Pro 222 mutants is examined, and properties of the mutants suggest that Pro 173 has a pivotal role in coupling proton flow to motor rotation and is positioned in the channel near Asp 32 of MotB.

Chemomechanical coupling without ATP: the source of energy for motility and chemotaxis in bacteria.

The source of energy for bacterial motility is the intermediate in oxidative phosphorylation, not ATP directly. For chemotaxis, however, there is an additional requirement, presumably ATP. These