Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Invisibility Cloak Needed for Cooperation?

08.09.2010
Unusual lipopolysaccharide enables symbiosis between bacterium and fungus

We and all other organisms must constantly grapple with bacteria. Whether for a necessary symbiosis or an infection, carbohydrate structures on cell surfaces play an important role in the interactions between bacteria and organisms.

A team led by Antonio Molinaro at the University of Naples and Christian Hertweck at the Leibniz Institute for Natural Product Research and Infection Biology in Jena have now discovered an unusual carbohydrate structure without which the symbiosis between a bacterium and a fungus that affects rice plants is not stable. As the researchers report in the journal Angewandte Chemie, the bacterium probably requires this structure as camouflage for protection against the defense mechanisms of the fungus.

In gram-negative bacteria, lipopolysaccharide (LPS) carbohydrate structures are especially important for cell–cell interactions. LPS consists of a complex chain made of various saccharide molecules and a lipid that anchors the structure in the cell membrane. “Previous studies were limited to the role of LPS in the interaction of bacteria with animals or plants,” says Hertweck. “There is thus a sizeable knowledge gap with respect to interaction with other microbes.” The team has now examined a singular symbiosis: The fungus Rhizopus microsporus, which causes rice blight, inhibits root growth in rice plants, causing the plants to die. To achieve this, the fungus needs a partner—the bacterium Burkholderia rhizoxinica. The bacteria produce toxins needed by the fungus to damage the rice plants. The nutrients released by the dead plants are then used by both symbiotic partners.

“Until now the mechanism that allows the bacteria to survive within the fungal cells has remained a mystery,” says Hertweck. Now the team seems to be on the heels of a solution. “We have found an unusual polysaccharide, a chain of several galactose molecules, in the LPS of the bacterium,” says Herweck. “This pattern has not been seen before in this class of bacteria; however similar structures often occur in fungi.” The bacterium possibly mimics these structural elements of its host organism. The researchers infected fungi with mutated bacteria that did not contain these polysaccharides. In this case, the partners are not able establish a stable symbiosis. This becomes evident when the fungi are no longer able to produce spores.

“The special galactose sequence probably acts as a disguise for the bacterium,” opines Hertweck. “It is possible that it is thus not recognized as foreign, which keeps it safe from the defense mechanism of the fungus.”

Author: Christian Hertweck, Leibniz-Institut für Naturstoff-Forschung und Infektionsbiologie, HKI, http://www.hki-jena.de/index.php/0/1/107

Title: An Unusual Galactofuranose Lipopolysaccharide That Ensures the Intracellular Survival of Toxin-Producing Bacteria in Their Fungal Host

Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201003301

Christian Hertweck | Angewandte Chemie
Further information:
http://www.hki-jena.de/index.php/0/1/107
http://pressroom.angewandte.org

More articles from Life Sciences:

nachricht More genes are active in high-performance maize
19.01.2018 | Rheinische Friedrich-Wilhelms-Universität Bonn

nachricht How plants see light
19.01.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Let the good tubes roll

19.01.2018 | Materials Sciences

How cancer metastasis happens: Researchers reveal a key mechanism

19.01.2018 | Health and Medicine

Meteoritic stardust unlocks timing of supernova dust formation

19.01.2018 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>