Forum für Wissenschaft, Industrie und Wirtschaft

Hauptsponsoren:     3M 
Datenbankrecherche:

 

Snapshot reveals details about photosynthesis

09.11.2012
Together with a large international research team, Johannes Messinger of Umeå University in Sweden has taken another step toward an understanding of photosynthesis and developing artificial photosynthesis.

With a combination of a x-ray free-electron laser and spectroscopy, the team has managed to see the electronic structure of a manganese complex, a chemical compound related to how photosynthesis splits water.


Caption: Ultra-short x-ray pulse striking molecules containing manganese. Illustration: Greg Stewart, National Accelerator Laboratory vid Stanford University

The experiments used the Linac Coherent Light Source (LCLS), which is a free-electron x-ray laser facility at Stanford University in the US. The wavelength of the laser is roughly the same as the breadth of an atom, and each pulse of light lasts 50 femtoseconds (10-15). This is an extremely short interval of time: there are more femtoseconds in one second than there are seconds in a person’s life. Such extremely short wavelengths and short light pulses constitute ideal conditions for imaging chemical reactions with atomic resolution at room temperature while the chemical reactions are ongoing.

The research group has previously used LCLS to perform structural analyses of isolated photosynthesis complexes from plants’ photosystem II at room temperature. Now the group has combined the method with spectroscopy and is the first team to succeed in seeing at LCLS the electronic structure of a manganese complex similar to that found in photosystem II. Manganese is a transitional metal that, together with calcium and oxygen, forms the water-splitting catalyst in photosystem II.

A very simple example of a spectrometer is a prism, which separates sunlight into all the colors of the rainbow. The spectrometer used in this study functions in a similar manner, but with a group of 16 specialized crystals that diffract the x-rays emitted from the sample in resonse of being excited by an x-ray pulse onto a detector array.

To the delight of the scientists, the manganese compounds remained intact long enough for them to observe detailed information about the electronic structure before the compounds were destroyed by the very intense X-ray laser beam.

“Having both structural information and spectroscopic information means that we can much better understand how the structural changes of the whole complex and the chemical changes on the active surface of the catalysts work together to enable the enzymes to perform complex chemical reactions at room temperature,” says Johannes Messinger, professor at the Department of Chemistry at Umeå University.

The chemical reaction the research group aims to understand is the splitting of water in photosystem II, as this understanding is also key for developing artificial photosynthesis– that is, for building devices for producing hydrogen from sunlight and water. To be able to exploit sunlight for producing fuels that can be stored and the used when needed would help solve the world’s ever-more acute energy problems.

The new research findings are being published in the highly regarded journal Proceedings of the National Academy of Sciences, PNAS.

Two major research projects at Umeå University are focusing on the development of artificial photosynthesis by imitating plants’ very successful way of exploiting solar energy. Both projects (“solar fuels” and “artificial leaf”) are directed by Johannes Messinger, professor at the Department of Chemistry at Umeå University.

Original publication:
Alonso-Mori Roberto, et. al: Energy-dispersive X-ray emission spectroscopy using an X-ray free-electron laser in a shot-by-shot mode. PNAS, November 5 2012, doi:10.1073/pnas.1211384109
For more information, please contact:
Johannes Messinger
Telephone: phone: +46 (0)90-786 59 33
E-mail: johannes.messinger@chem.umu.se

Ingrid Söderbergh | idw
Further information:
http://www.vr.se

More articles from Life Sciences:

nachricht Genetic Regulation of the Thymus Function Identified
23.08.2016 | Universität Basel

nachricht Sun protection for plants - Plant substances can protect plants against harmful UV radiation
22.08.2016 | Max-Planck-Institut für Molekulare Pflanzenphysiologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Mikroskopieren mit einzelnen Ionen

Neuartiges Ionenmikroskop nutzt einzelne Ionen, um Abbildungen mit einer Auflösung im Nanometerbereich zu erzeugen

Wissenschaftler um Georg Jacob von der Johannes Gutenberg-Universität Mainz haben ein Ionenmikroskop entwickelt, das nur mit exakt einem Ion pro Bildpixel...

Im Focus: Streamlining accelerated computing for industry

PyFR code combines high accuracy with flexibility to resolve unsteady turbulence problems

Scientists and engineers striving to create the next machine-age marvel--whether it be a more aerodynamic rocket, a faster race car, or a higher-efficiency jet...

Im Focus: Neues DFKI-Projekt SELFIE schlägt innovativen Weg in der Verifikation cyber-physischer Systeme ein

Vor der Markteinführung müssen neue Computersysteme auf ihre Korrektheit überprüft werden. Jedoch ist eine vollständige Verifikation aufgrund der Komplexität heutiger Rechner aus Zeitgründen oft nicht möglich. Im nun gestarteten Projekt SELFIE verfolgt der Forschungsbereich Cyber-Physical Systems des Deutschen Forschungszentrums für Künstliche Intelligenz (DFKI) unter Leitung von Prof. Dr. Rolf Drechsler einen grundlegend neuen Ansatz, der es Systemen ermöglicht, sich nach der Produktion und Auslieferung selbst zu verifizieren. Das Bundesministerium für Bildung und Forschung (BMBF) unterstützt das Vorhaben über drei Jahre mit einer Fördersumme von 1,4 Millionen Euro.

In den letzten Jahrzehnten wurden enorme Fortschritte in der Computertechnik erzielt. Ergebnis dieser Entwicklung sind eingebettete und cyber-physische...

Im Focus: „Künstliches Atom“ in Graphen-Schicht

Elektronen offenbaren ihre Quanteneigenschaften, wenn man sie in engen Bereichen gefangen hält. Ein Forschungsteam mit TU Wien-Beteiligung baut Elektronen-Gefängnisse in Graphen.

Wenn man Elektronen in einem engen Gefängnis einsperrt, dann benehmen sie sich ganz anders als im freien Raum. Ähnlich wie die Elektronen in einem Atom können...

Im Focus: X-ray optics on a chip

Waveguides are widely used for filtering, confining, guiding, coupling or splitting beams of visible light. However, creating waveguides that could do the same for X-rays has posed tremendous challenges in fabrication, so they are still only in an early stage of development.

In the latest issue of Acta Crystallographica Section A: Foundations and Advances , Sarah Hoffmann-Urlaub and Tim Salditt report the fabrication and testing of...

Alle Focus-News des Innovations-reports >>>

Anzeige

Anzeige

IHR
JOB & KARRIERE
SERVICE
im innovations-report
in Kooperation mit academics
Veranstaltungen

Neue Ideen für die Schifffahrt

24.08.2016 | Veranstaltungen

E-Health, E-Hygiene, IT-Management und IT-Sicherheit: Trends und Chancen für Kliniken und Praxen

24.08.2016 | Veranstaltungen

HTW Berlin richtet im September die 30. EnviroInfo aus

23.08.2016 | Veranstaltungen

 
B2B-VideoLinks
Weitere VideoLinks >>>
Aktuelle Beiträge

Neue Ideen für die Schifffahrt

24.08.2016 | Veranstaltungsnachrichten

Mikroskopieren mit einzelnen Ionen

24.08.2016 | Informationstechnologie

E-Health, E-Hygiene, IT-Management und IT-Sicherheit: Trends und Chancen für Kliniken und Praxen

24.08.2016 | Veranstaltungsnachrichten