Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tracking Prions

17.06.2008
Magnetic resonance studies find clear differences between the structures of infectious and non-infectious prions

Infectious proteins known as prions have been identified as the cause of ¡°mad cow¡± disease (BSE). The culprits are ¡°incorrectly folded¡± proteins that can ¡°infect¡± healthy proteins. The molecular bases for such prion diseases are not yet fully understood.

Why are some proteins infectious while others are not? A team headed by Beat Meier (ETH Zurich, Switzerland) and Raimon Sabat¨¦ (University of Bordeaux, France) has examined two different forms of a prion-forming protein domain by means of NMR spectroscopy. In the journal Angewandte Chemie, the researchers report that the infectious and non-infectious forms differ markedly in their molecular structure.

The word prion is derived from the term Proteinaceous Infectious Particle. These are proteins that can fold in different ways. Pathogenic prions are dangerous because they can convert physiological, non-pathogenic molecules into the diseased form. Often, prions largely consist of ¦Â-sheet structures. These are accordion-like folded protein ribbons that can easily aggregate into thread-like structures (amyloid fibrils).

... more about:
»Infectious »Molecular »NMR »Prion »Protein »fibrils

The research team took on the prion-forming domain of the fungal protein HET-s. At a pH value of 7¡ªunder physiological conditions¡ªthis domain forms infectious fibrils. In acidic solution, at pH 3, it also forms fibrils, but these are not infectious.

By using nuclear magnetic resonance spectroscopy (NMR), the team was able to get a closer look at this protein. NMR allows for the evaluation of interactions of the nuclear spins of specific atomic nuclei with each other and their chemical surroundings, which gives information about the structure and dynamics of molecules and molecular fragments.

Here¡¯s what the researchers found: The spectra of the pH 7 and pH 3 versions of the prion differ significantly. Both are mainly arranged in the rigid ¦Â-sheet structure, but up close the structures diverge widely. Particularly striking is the fact that the infectious pH 7 form has highly flexible loops in addition to the rigid domains. These are absent from the non-infectious pH 3 prions.

¡°The lack of infectiousness of the pH 3 fibrils is thus related to the fact that their molecular structure is significantly different from that of the fibrils formed at physiological pH,¡± the researchers conclude.

Author: Beat H. Meier, ETH Z¨¹rich (Switzerland), http://www.ssnmr.ethz.ch/people/meierbe

Title: Infectious and Noninfectious Amyloids of the HET-s(218¨C289) Prion Have Different NMR Spectra

Angewandte Chemie International Edition, doi: 10.1002/anie.200704896

Beat H. Meier | Angewandte Chemie
Further information:
http://pressroom.angewandte.org
http://www.ssnmr.ethz.ch/people/meierbe

Further reports about: Infectious Molecular NMR Prion Protein fibrils

More articles from Life Sciences:

nachricht Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz

nachricht Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB

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

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | 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

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>