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 Researchers develop eco-friendly, 4-in-1 catalyst
25.04.2017 | Brown University

nachricht Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017
25.04.2017 | Laser Zentrum Hannover e.V.

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

NASA's Fermi catches gamma-ray flashes from tropical storms

25.04.2017 | Physics and Astronomy

Researchers invent process to make sustainable rubber, plastics

25.04.2017 | Materials Sciences

Transfecting cells gently – the LZH presents a GNOME prototype at the Labvolution 2017

25.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>