Just a few weeks ago, teams from Bochum, Illinois, and Nevada were able to prove with terahertz (THz) spectroscopy that proteins do modify water molecules in their environment to a long range extent: The water molecules, which generally move around like disco dancers in their collective network motions behave more like in a neat minuet under protein influence.
The group by Prof. Dr. Martina Havenith-Newen (Physical Chemistry II Dpt., RUB) managed to find out more about the rules of this dance. They could show that protein folding changes the dancing steps of the water. A partly unfolded protein will affect water molecules within the dynamical hydration shell to a much less extent than a folded one does. The higher the flexibility of the protein, the less affected is the water. The scientists present their conclusions as a "communication" in the Journal of the American Chemical Society.
Protein Creates Order in Water
In water, weak bonds between two adjacent water molecules, referred to as the hydrogen bridge bonds, are continuously opening and closing: this happens on average every 1.3 pico seconds (one pico second = 10 power -12 seconds). "Even small concentrations of proteins in water lead to measurable changes in collective movements", Prof. Havenith-Newen explains the results of previous studies with THz spectroscopy.
The Folding is the Important Thing
While the folded protein affects up to 1,000 water molecules in its environment, this is only true for the partly unfolded protein to a small extent. If one modifies some parts of the protein through mutation, the effect is less remarkable. These observations were now made by the scientific teams of Prof. Havenith-Newen, Prof. Dr. Martin Gruebele, and Prof. Dr. David M. Leitner from RUB, the University of Illinois and the University of Nevada, respectively. "This shows that water in the environment of folded proteins is different from that in the environment of an unfolded protein", Prof. Havenith-Newen concludes. "This will further support the hypothesis that protein and water are not independent of each other and do influence each other - an effect which has been considered decisive for protein folding, and which may be highly important for protein functions."
New, Highly Precise Method of Proof
THz spectroscopy is a new, especially sensitive method of observing fast water network movement in the close vicinity of proteins with the THz frequencies ranging between microwave and infrared frequencies. Particularly strong THz laser radiation sources lasers, which has been used in chemistry for the first time by RUB, facilitates the observation of proteins in their natural environment during their fast dance with water molecules. The studies which have been published in the Journal of the American Chemical Society were financed by the Human Frontier Science Programme. Martin Gruebele has stayed at the RUB Chemistry Department after being awarded the Friedrich Wilhelm Bessel prize of the Alexander von Humboldt foundation.
S. Ebbinghaus, S. J. Kim, M. Heyden, X. Yu, M. Gruebele, D.M. Leitner, and M. Havenith: Protein sequence- and pH-dependent hydration probed by Terahertz spectroscopy. In: Journal of the American Chemical Society, ASAP Article 10.1021/ja0746520 S0002-7863(07)04652-5, Web Release Date: February 5, 2008, Copyright © 2008 American Chemical Society, http://pubs.acs.org/cgi-bin/abstract.cgi/jacsat/asap/abs/ja0746520.html
Prof. Dr. Martina Havenith-Newen, Fakulty of Chemistry and Biochemistry at Ruhr-Universität Bochum, Tel. 0234/32-24249, Fax: 0234/32-14183, E-Mail: email@example.com
Dr. Josef König | idw
Oestrogen regulates pathological changes of bones via bone lining cells
28.07.2017 | Veterinärmedizinische Universität Wien
Programming cells with computer-like logic
27.07.2017 | Wyss Institute for Biologically Inspired Engineering at Harvard
Spectrally narrow x-ray pulses may be “sharpened” by purely mechanical means. This sounds surprisingly, but a team of theoretical and experimental physicists developed and realized such a method. It is based on fast motions, precisely synchronized with the pulses, of a target interacting with the x-ray light. Thereby, photons are redistributed within the x-ray pulse to the desired spectral region.
A team of theoretical physicists from the MPI for Nuclear Physics (MPIK) in Heidelberg has developed a novel method to intensify the spectrally broad x-ray...
Physicists working with researcher Oriol Romero-Isart devised a new simple scheme to theoretically generate arbitrarily short and focused electromagnetic fields. This new tool could be used for precise sensing and in microscopy.
Microwaves, heat radiation, light and X-radiation are examples for electromagnetic waves. Many applications require to focus the electromagnetic fields to...
Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers
Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...
Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.
At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...
3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects
A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...
26.07.2017 | Event News
21.07.2017 | Event News
19.07.2017 | Event News
28.07.2017 | Health and Medicine
28.07.2017 | Power and Electrical Engineering
28.07.2017 | Life Sciences