Study on how bacteria move could help researchers develop anti-bacterial surfaces

Jul 25, 2011

Jacinta Conrad, an assistant professor of chemical and biomolecular engineering at the University of Houston, likens her research into how bacteria move to "tracking bright spots on a dark background."

Using a digital camera affixed to a microscope, Conrad and her collaborators videotape hours of moving . They then analyze these tens of thousands of images to determine exactly how they cross surfaces before forming biofilms, colonies of potentially that can be found in industrial, natural and hospital environments.

Conrad has co-authored an article on the subject that is featured in the new issue of the (PNAS), one of the nation's most prestigious .

"This marks another step in our effort to fully understand how bacteria move along a surface," said Conrad, who co-authored a related paper that appeared last fall in Science.

Understanding how bacteria move on their way to forming biofilms could lead to discovering ways to hinder or prevent this process.

Biofilms can form on food processing equipment, potentially leading to food-borne illnesses, and on , leading to high rates of infection in hospitals. They also can disrupt the flow of sewage and oil pipelines and increase drag on marine vessels, slowing ships and wasting fuel, among other things.

In the Science paper, Conrad and her collaborators detailed how bacteria use hair-like called pili to pull themselves upright and "walk" across a surface.

The research in the PNAS paper builds on that finding, with researchers discovering that the bacteria employ a "slingshot" motion to move using multiple pili, which act as grappling hooks. Conrad said that bacteria rapidly "snap" to a new orientation when they release one pilus, while others remain attached. This is because the bacteria re-orients in the direction of the net force from the remaining attached pili.

"We think the bacteria use this rapid-snap motion to move forward," she said. "We believe that this method allows the bacteria to move faster and more efficiently across a surface through this sticky, viscous pre-matrix substance that surrounds it. The bacteria may use less energy this way."

Bacteria often move along a surface to form biofilms, which develop on surfaces and are shielded by an extracellular matrix of polymers. The bacteria excrete polymers as they move, which forms the basis for this shield.

This substance can be very thick and difficult to move through. The researchers hypothesize that the "slingshot" motion thins the sticky goo and makes it easier for the bacteria to travel through it. The next step is for Conrad and her collaborators to thoroughly test this hypothesis.

Explore further: Researchers discover new mechanism of DNA repair

Related Stories

Researchers discover 'walking' properties of bacteria

Oct 08, 2010

(PhysOrg.com) -- Many drug-resistant infections are the result of bacterial biofilms, structured aggregates of bacteria that live on surfaces and that are extremely resistant to environmental stresses. These ...

Biofilms use chemical weapons

Jul 23, 2008

Bacteria rarely come as loners; more often they grow in crowds and squat on surfaces where they form a community together. These so-called biofilms develop on any surface that bacteria can attach themselves ...

Recommended for you

Researchers discover new mechanism of DNA repair

21 hours ago

The DNA molecule is chemically unstable giving rise to DNA lesions of different nature. That is why DNA damage detection, signaling and repair, collectively known as the DNA damage response, are needed.

Stopping Candida in its tracks

Jul 03, 2015

Scientists are one step closer to understanding how a normally harmless fungus changes to become a deadly infectious agent.

New technique maps elusive chemical markers on proteins

Jul 02, 2015

Unveiling how the 20,000 or so proteins in the human body work—and malfunction—is the key to understanding much of health and disease. Now, Salk researchers developed a new technique that allows scientists ...

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.