Differential Dynamic Microscopy of Bacterial Motility
Abstract
We demonstrate a method for the fast, high-throughput characterization of the dynamics of active particles. Specifically, we measure the swimming speed distribution and motile cell fraction in Escherichia coli suspensions. By averaging over ∼104 cells, our method is highly accurate compared to conventional tracking, yielding a routine tool for motility characterization. We find that the diffusivity of nonmotile cells is enhanced in proportion to the concentration of motile cells.
- Publication:
-
Physical Review Letters
- Pub Date:
- January 2011
- DOI:
- arXiv:
- arXiv:1004.4764
- Bibcode:
- 2011PhRvL.106a8101W
- Keywords:
-
- 87.17.Jj;
- 82.70.Dd;
- 87.80.-y;
- Cell locomotion;
- chemotaxis and related directed motion;
- Colloids;
- Biological techniques and instrumentation;
- biomedical engineering;
- Quantitative Biology - Quantitative Methods;
- Condensed Matter - Soft Condensed Matter;
- Physics - Biological Physics;
- Quantitative Biology - Cell Behavior
- E-Print:
- 4 pages, 4 figures. In this updated version we have added simulations to support our interpretation, and changed the model for the swimming speed probability distribution from log-normal to a Schulz distribution. Neither modification significantly changes our conclusions