Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Social mobility: Study shows bacteria seek each other out


A study by Princeton University scientists has shown that bacteria actively move around their environments to form social organizations. The researchers placed bacteria in minute mazes and found that they sought each other out using chemical signals.

Biologists have become increasingly aware of social interactions among bacteria, but previously believed that clusters formed only when bacteria randomly landed somewhere, then multiplied into dense populations. The discovery that they actively move into gatherings underscores the importance of bacterial interactions and could eventually lead to new drugs that disrupt the congregating behavior of harmful germs, said Jeffry Stock, a professor of molecular biology and co-author of the paper.

"It makes sense, but it’s surprising that it’s as pervasive as it now seems to be," said Stock.

The researchers observed the gathering behavior in E. coli as well as in V. harveyi, a marine bacteria that glows when it achieves a high-density population. They found that when placed in mazes the bacteria congregated in small rooms and dead-end pathways. Once clustered, the V. harveyi turned on the genes that make them glow.

Biologists had previously believed that bacteria’s ability to move and follow chemical signals - a process called chemotaxis - was primarily a means of dispersing and seeking food. The new study shows that chemotaxis may also be important for facilitating cooperative behavior.

The work was a collaboration between Stock’s lab in biology and that of Robert Austin, a professor of physics. Emil Yuzbashyan, a graduate student in Austin’s noticed unusual clumping when he put E. coli into microscopically small mazes made of silicone. Biologists in Stock’s lab supplied mutant strains of bacteria that lacked genes necessary for sensing chemical signals and chemotaxis. They found that bacteria themselves emit a key chemical attractant and that those lacking the gene for the receptor that senses that attractant did not cluster as normal bacteria did.

Disrupting chemotaxis could be a route to attacking biofilms, a common type of bacterial interaction in which they form a colony that is resistant to antibiotic drugs and chemicals, the researchers said. Biofilms pose a common danger to patients receiving medical implants and cause trouble for ships that develop biofilms on their hulls.

Clustering also allows bacteria to perform a coordinated activity called quorum sensing in which they turn on certain genes only when they sense that they are part of a dense population. Some disease-causing bacteria are believed to rely on quorum sensing in mounting a successful infection. The V. harveyi in the experiment glowed as a result of quorum sensing after they gathered into a dense population.

"Our paper points out that you don’t necessarily need growth to achieve quorum sensing," said Peter Wolanin, a postdoctoral researcher in Stock’s lab. "The bacteria can actively seek each other out to engage in collective social behavior."

The behavior observed in the experiment also may have been a survival mechanism, said Sungsu Park, a postdoctoral researcher in Austin’s lab and first author of the paper. The research was conducted with the bacteria in a nutrient-depleted environment that resembles the natural conditions for bacteria much of the time. "The bacteria are chasing amino acids released from their own cell bodies during starvation conditions," said Park. "So by getting close to each other they have a better chance of getting nutrients."

The researchers also have developed a mathematical model that simulates the bacterial congregation, said Park. They plan further research to investigate the relation between bacterial behavior and the size and geometry of their physical environment.

| Princeton University
Further information:

More articles from Life Sciences:

nachricht When fat cells change their colour
28.10.2016 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht Aquaculture: Clear Water Thanks to Cork
28.10.2016 | Technologie Lizenz-Büro (TLB) der Baden-Württembergischen Hochschulen GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel light sources made of 2D materials

Physicists from the University of Würzburg have designed a light source that emits photon pairs. Two-photon sources are particularly well suited for tap-proof data encryption. The experiment's key ingredients: a semiconductor crystal and some sticky tape.

So-called monolayers are at the heart of the research activities. These "super materials" (as the prestigious science magazine "Nature" puts it) have been...

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Prototype device for measuring graphene-based electromagnetic radiation created

28.10.2016 | Power and Electrical Engineering

Gamma ray camera offers new view on ultra-high energy electrons in plasma

28.10.2016 | Physics and Astronomy

When fat cells change their colour

28.10.2016 | Life Sciences

More VideoLinks >>>