Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study shows prions stick around in certain soils

11.09.2003


Dirt may help scientists answer a question that has baffled them for decades: How does chronic wasting disease (CWD) in deer and elk spread from animal to animal?

By turning to the land, University of Wisconsin-Madison researchers show that prions - infectious proteins considered to be at the root of the disease - literally stick to some soil types, suggesting that the landscape may serve as an environmental reservoir for the disease.

The findings will be discussed during a poster presentation on Wednesday, Sept. 10, in New York City at the 226th national meeting of the American Chemical Society.



Extraordinarily resistant to a range of environmental conditions and decontamination measures, prions are abnormally folded proteins that can make an animal’s brain as holey as a sponge. They’ve been implicated as the cause of diseases such as mad cow and scrapie in sheep.

Once infected, deer and elk, for example, experience a number of neurological and behavioral problems - staggering, shaking and excessive salivation, thirst and urination - until they waste away, many times dying in fields or woods. The disease is always fatal, and, to date, there is no cure.

Even though chronic wasting disease was first detected in free-ranging deer and elk in Colorado and Wyoming during the mid-1980s, it received a charge in scientific and public interest in February 2002, when the first evidence of the disease in Wisconsin appeared.

"The route by which CWD is transmitted from animal to animal is not understood," says Joel Pedersen, an environmental chemist and lead investigator on the soil study. "Strong circumstantial evidence suggests an environmental reservoir exists." Reports show, for instance, that healthy elk placed in pens where animals infected with CWD had once lived developed the fatal disease.

With funding from a recently awarded five-year, $2.4 million grant from the Department of Defense’s National Prion Research Program, Pedersen and his colleagues are examining the ability of the infectious agent to associate with or be absorbed by certain soil particles.

"Soil is a candidate [as an environmental reservoir] because grazing animals ingest it both inadvertently, as part of feeding, and on purpose, as part of certain deer behaviors," explains Pedersen.

To begin to understand how the disease stays in the environment, Pedersen and his colleagues turned to sand and clay - common components found in soils. Because of differences in surface area and mineral composition, Pedersen says sand and clay represent different ends of the spectrum in the ability to absorb proteins.

From the study’s results, the capacity of sand and clay to take up abnormally folded proteins, says the lead researcher, "differs dramatically."

Pedersen and his colleagues determined this by taking samples of sand and clay and adding infectious prions taken from hamsters, as well as a water-based solution representing one found naturally in soils. After removing the water and doing further analysis, they noticed that many of the prions in the sand mixture remained in the water solution, whereas those in the clay mixture stuck to the particles’ surface.

"Almost all the prions in the clay mixture associated with the clay, not the water," says Pedersen, adding that this finding suggests that the movement of prions through the landscape depends on the soil environment.

Understanding how the infectious agent moves - or, in the case of soils with high clay concentrations, stays put - could lead to new information on disease transmission or techniques for managing CWD. For instance, Pedersen says, "If we decide to bury infected carcasses, a clay liner underneath the landfill may be a good idea."

But while clay soils may work to contain infection, they may also help spread it. Whereas prions in sandy soils either may wash away or travel deeper into the ground, says Pedersen, those in clay soils may remain near the surface. "Because the material may be more available for ingestion by animals," he explains, "the rate of infection may be greater."

Analyzing the absorption capacity of sand and clay is just the first step, says Pedersen. In addition to quantifying the ability of prions to bind to these two soil components, they’ll consider other soil materials, additional soil minerals and organic matter. Also under way are studies to determine the degree to which prions in different soil types remain infectious.

"What we’ll be getting at is if prions are more likely to persist in some environments," says Pedersen, adding that results from all these studies will help natural resource managers and other experts perform risk assessments for the spread of CWD and similar diseases across the landscape. "Understanding the role of soil in the spread of CWD is critical in designing and implementing effective disease strategies."


###
- Emily Carlson 608-262-9772, emilycarlson@wisc.edu

Joel Pedersen | EurekAlert!
Further information:
http://www.wisc.edu/

More articles from Life Sciences:

nachricht Transport of molecular motors into cilia
28.03.2017 | Aarhus University

nachricht Asian dust providing key nutrients for California's giant sequoias
28.03.2017 | University of California - Riverside

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Researchers shoot for success with simulations of laser pulse-material interactions

29.03.2017 | Materials Sciences

Igniting a solar flare in the corona with lower-atmosphere kindling

29.03.2017 | Physics and Astronomy

As sea level rises, much of Honolulu and Waikiki vulnerable to groundwater inundation

29.03.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>