Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bochum’s researchers discover proton diode

02.09.2010
Water is an active element in proteins
Report in Angewandte Chemie

Biophysicists in Bochum have discovered a diode for protons: just like the electronic component determines the direction of flow of electric current, the “proton diode” ensures that protons can only pass through a cell membrane in one direction. Water molecules play an important role here as active components of the diode.

The researchers led by Prof. Dr. Klaus Gerwert (Chair of Biophysics at the RUB) were able to observe this through a combination of molecular biology, X-ray crystallography, time-resolved FTIR spectroscopy and biomolecular simulations. They report in the current international online edition of the journal Angewandte Chemie.

Protons drive the protein turbines

The proton diode plays an important role in the energy production of cells. Light-driven proton pumps - certain proteins that traverse the cell membrane - eject protons out of the cell, so that excess pressure is generated outside “much like the water pressure at a dam”, explains Prof. Gerwert. Elsewhere, the protons push back into the cells to compensate the concentration gradient, and thereby drive the turbines of the cell, proteins known as ATPases. The energy thus released is converted into the universal fuel of the cells, ATP (adenosine triphosphate). “This process is a kind of archaic photosynthesis” explains Prof. Gerwert. “The light energy is ultimately converted into usable energy for the organism”.

We used to believe in chance

The details of these processes are the subject of research. In particular, the role of water molecules in proteins has long been unclear. “Previously it was believed that the water molecules blundered into the proteins by chance, and fulfilled no particular function”, says Gerwert. Manfred Eigen, born in Bochum in 1967, was awarded the Nobel Prize for chemistry because he was able to explain why water and ice protons are such rapid conductors. The current work shows that proteins also use precisely this mechanism and that the water molecules do indeed carry out an active function in the protein.

Water is as important as amino acids

This result supports the hypothesis drawn up by Klaus Gerwert in 2006 in Nature that protein-bound water molecules are just as important catalytic elements for the function of proteins as amino acids, the building blocks of life. Consequently, the Bochum biophysicists have devoted their work in Angewandte Chemie to Manfred Eigen. Eigen also published his central thesis on proton transfer in water in Angewandte Chemie in 1964. Klaus Gerwert was inspired by Manfred Eigen’s winter seminars in Klosters.

Film instead of fixed image

The Bochum researchers were able to achieve their results in an interdisciplinary approach through a combination of molecular biology, X-ray crystallography, time-resolved FTIR spectroscopy and biomolecular simulations. This combination shows the dynamic processes in the protein after light excitation with atomic resolution. “You can track how the proton is transported from the central proton binding site inside the protein via an amino acid and then via a protonated water cluster to the membrane surface”, says Prof. Gerwert. The interdisciplinary approach is now expanding the classical methods of structural biology, X-ray crystallography and nuclear magnetic resonance spectroscopy (NMR), as it provides a complete film and not just fixed images of proteins. The experiments in Bochum were supplemented by computer simulations in Shanghai. Klaus Gerwert is both a professor at the RUB and Director of the Max Planck Partner Institute for Computational Biology in Shanghai.

Bibliographic record

Wolf, S., Freier, E., Potschies, M., Hofmann, E. and Gerwert, K.: “Directional Proton Transfer in Membrane Proteins Achieved through Protonated Protein-Bound Water Molecules: A Proton Diode” Angewandte Chemie International Edition, DOI: 10.1002/anie.201001243

Garczarek, F., Gerwert, K.: “Functional waters in intraprotein proton transfer monitored by FTIR difference spectroscopy”. In: Nature 439, 109-112 (2006)

Further information

Prof. Dr. Klaus Gerwert, Chair of Biophysics at the Ruhr-Universität Bochum, 44780 Bochum, ND 04/596, Tel. 0234/32-24461, gerwert@bph.rub.de

Editor: Meike Drießen

Dr. Josef König | idw
Further information:
http://www.ruhr-uni-bochum.de/

More articles from Life Sciences:

nachricht Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel

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

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

Scientist invents way to trigger artificial photosynthesis to clean air

26.04.2017 | Materials Sciences

Ammonium nitrogen input increases the synthesis of anticarcinogenic compounds in broccoli

26.04.2017 | Agricultural and Forestry Science

SwRI-led team discovers lull in Mars' giant impact history

26.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>