Featured Research

from universities, journals, and other organizations

Mycotoxin protects against nematodes, study finds

Date:
May 27, 2014
Source:
ETH Zürich
Summary:
Most terrestrial plants enter into biocoenosis with funghi. Both sides benefit: the fungus, which surrounds the small roots of the host plant with a thick felt, supplies the plant with trace elements and water. The plant, in turn, supplies the fungus with sugars and other metabolites which it is unable to produce itself.

The fungal toxin binds to specific sugar structures which occur on the surface of intestinal cells of the nematode Caenorhabditis elegans. Where the toxin accumulates the surface is glowing bright red.
Credit: Alex Butschi / University of Zürich

Most terrestrial plants enter into biocoenosis with funghi. Both sides benefit: the fungus, which surrounds the small roots of the host plant with a thick felt, supplies the plant with trace elements and water. The plant, in turn, supplies the fungus with sugars and other metabolites which it is unable to produce itself.

Toxic protein kills intestinal cells

ETH researchers from the research group of microbiology professor Markus Aebi have discovered a protein in the cells of one such ectomycorrhizal fungus which offers an additional advantage to the fungus-plant duo. It protects the fungus and possibly its roots, too, against nematodes as it is toxic to the parasites. "This toxin is probably part of this fungus' defence system against predators," says Markus Künzler, senior assistant in Aebi's group. If the nematodes feed on the fungal cells, they ingest the toxic protein. The nematode's intestinal cells are destroyed by a mechanism which has still to be elucidated.

The mushroom mainly forms the protein in its pileus, i.e. the part of the fruiting body visible above ground and in the dense fungal net around the tips of the roots. The fact that the toxin is close to the root tips could be an indication that the toxin not only protects the fungus but also the plant roots against predators. Many nematodes that live in the soil feed not only on fungal tissue but also on plant cells.

Modified sugar as the docking station

In their study, which has just been published in the journal PNAS, the researchers demonstrate that the defence protein docks on to a specific target in the nematode : a modified sugar found on the surfaces of the worm's intestinal cells but also on those of molluscs like snails. However, there doesn't seem to be any such surface structure on the cells of vertebrates.

Furthermore, Künzler and his colleagues show that this point of attack is also found in specific bacteria which means that the toxic protein can also dock on there. As the protein has several binding points for the target structure, the protein and several bacteria form clumps, they "agglutinate."

"This reaction is interesting as close relatives of this protein, known as homologs have also been found in animals -- ranging from invertebrates like the horseshoe crab to humans -- where they play a role in the defence against bacteria," continues Künzler.

The fact that fungal and animal toxic proteins bind to the same target structures means that this defence mechanism must be very old in terms of evolution. This type of defence is part of the "innate" defence system of highly diverse organism groups like mushrooms, crabs or even humans.

Vaccinate livestock against parasites

This finding also paves the way for practical applications: the ETH spin-off Malcisbo, which came from the microbiologist's laboratory, endeavours, on the basis of these surface sugar structures to develop novel vaccines against parasites and pathogenic germs for livestock and humans. "The funghi reveal to us the Achilles heel of nematodes and bacteria. We can now use these findings to combat them," hopes Künzler.


Story Source:

The above story is based on materials provided by ETH Zürich. The original article was written by Peter Rüegg. Note: Materials may be edited for content and length.


Journal Reference:

  1. Wohlschlager T, et al. Methylated glycans as conserved targets of animal and fungal innate defense. PNAS, May 2014 DOI: 10.1073/pnas.1401176111

Cite This Page:

ETH Zürich. "Mycotoxin protects against nematodes, study finds." ScienceDaily. ScienceDaily, 27 May 2014. <www.sciencedaily.com/releases/2014/05/140527085516.htm>.
ETH Zürich. (2014, May 27). Mycotoxin protects against nematodes, study finds. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/2014/05/140527085516.htm
ETH Zürich. "Mycotoxin protects against nematodes, study finds." ScienceDaily. www.sciencedaily.com/releases/2014/05/140527085516.htm (accessed September 16, 2014).

Share This



More Plants & Animals News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) — The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

AFP (Sep. 16, 2014) — Scientists say a female colossal squid weighing an estimated 350 kilograms (770 lbs) and thought to be only the second intact specimen ever found was carrying eggs when discovered in the Antarctic. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com
Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) — Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

AFP (Sep. 16, 2014) — Since the arrival of Ebola in Ivory Coast, Ivorians have been abandoning their pets, particularly monkeys, in the fear that they may transmit the virus. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

      Technology News



      Save/Print:
      Share:  

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile iPhone Android Web
      Follow Facebook Twitter Google+
      Subscribe RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins