Engineers track bacteria's kayak paddle-like motion for first time

Sep 25, 2009

Yale engineers have for the first time observed and tracked E. coli bacteria moving in a liquid medium with a motion similar to that of a kayak paddle.

Their findings, which appear online September 29 in the journal Physical Review Letters, will help lead to a better understanding of how bacteria move from place to place and, potentially, how to keep them from spreading.

Scientists have long theorized that the cigar-shaped cell bodies of E. coli and other would follow periodic orbits that resemble the motion of a kayak paddle as they drift downstream in a current. Until now, no one had managed to directly observe or track those movements.

Hur Koser, associate professor at Yale's School of Engineering & Applied Science, previously discovered that hydrodynamic interactions between the bacteria and the current align the bacteria in a way that allows them to swim upstream. "They find the most efficient route to migrate upstream, and we ultimately want to understand the mechanism that allows them to do that," Koser said.

The team took sequential images of the E. coli bacteria to track their movements, which resemble the motion of a kayak paddle, through a liquid medium. Credit: Hur Koser/Yale University

In the new study, Koser, along with postdoctoral associate and lead author of the paper, Tolga Kaya, devised a method to see this motion in progress. They used advanced computer and imaging technology, along with sophisticated new algorithms, that allowed them to take millions of high-resolution images of tens of thousands of individual, non-flagellated E. coli drifting in a water and glycerin solution, which amplified the bacteria's paddle-like movements.

The team characterized the bacteria's motion as a function of both their length and distance from the surface. The team found that the longer and closer to the surface they were, the slower the E. coli "paddled."

It took the engineers months to perfect the intricate camera and computer system that allowed them to take 60 to 100 sequential images per second, then automatically and efficiently analyze the huge amount of resulting data.

This video is not supported by your browser at this time.
Yale engineers for the first time captured the kayak paddle-like motion of E. coli bacteria "paddling" in a liquid medium. Credit: Hur Koser/Yale University

E. coli and other bacteria can colonize wherever there is water and sufficient nutrients, including the human digestive tract. They encounter currents in many settings, from riverbeds to home plumbing to irrigation systems for large-scale agriculture.

"Understanding the physics of bacterial movement could potentially lead to breakthroughs in the prevention of bacterial migration and sickness," Koser said. "This might be possible through mechanical means that make it more difficult for to swim upstream and contaminate water supplies, without resorting to antibiotics or other chemicals."

Source: Yale University (news : web)

Explore further: Finding faster-than-light particles by weighing them

add to favorites email to friend print save as pdf

Related Stories

Mixing it up with E. coli

Jan 15, 2007

Poetry in motion may seem like an odd way to describe swimming bacteria, but that's what researchers at Drexel University got when they enlisted Escherichia coli (E. coli) in an effort to tackle a major problem in developing ...

Resistant gut bacteria will not go away by themselves

Jun 19, 2007

E. coli bacteria that have developed resistance to antibiotics will probably still be around even if we stop using antibiotics, as these strains have the same good chance as other bacteria of continuing to colonise the gut, ...

Recommended for you

Finding faster-than-light particles by weighing them

Dec 26, 2014

In a new paper accepted by the journal Astroparticle Physics, Robert Ehrlich, a recently retired physicist from George Mason University, claims that the neutrino is very likely a tachyon or faster-than-light par ...

Controlling core switching in Pac-man disks

Dec 24, 2014

Magnetic vortices in thin films can encode information in the perpendicular magnetization pointing up or down relative to the vortex core. These binary states could be useful for non-volatile data storage ...

World's most complex crystal simulated

Dec 24, 2014

The most complicated crystal structure ever produced in a computer simulation has been achieved by researchers at the University of Michigan. They say the findings help demonstrate how complexity can emerge ...

Atoms queue up for quantum computer networks

Dec 24, 2014

In order to develop future quantum computer networks, it is necessary to hold a known number of atoms and read them without them disappearing. To do this, researchers from the Niels Bohr Institute have developed ...

New video supports radiation dosimetry audits

Dec 23, 2014

The National Physical Laboratory (NPL), working with the National Radiotherapy Trials Quality Assurance Group, has produced a video guideĀ to support physicists participating in radiation dosimetry audits.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.