Escherichia coli use long, whip-like structures called flagella to propel themselves. Motors in the cell's wall spin the flagella into bundles that rotate counter-clockwise, creating a twist that causes the bacterium to rotate clockwise, or towards the right when viewed from above.
Insight into bacterial micro-movement will benefit scientists and engineers developing nanoscale mechanical devices that may one day push fluids and transport molecules without the aid of pumps or electrical charges. The findings may also help elucidate how pathogens traverse the human body when causing disease.
This image accompanied NSF press release, "Bacteria Take the Path of Least Resistance." http://www.nsf.gov/news/news_summ.jsp?cntn_id=104283&preview=false
Credit: Nicolle Rager Fuller, National Science Foundation