Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

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 Show me your leaves - Health check for urban trees
12.12.2017 | Gesellschaft für Ökologie e.V.

nachricht Liver Cancer: Lipid Synthesis Promotes Tumor Formation
12.12.2017 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Long-lived storage of a photonic qubit for worldwide teleportation

12.12.2017 | Physics and Astronomy

Multi-year submarine-canyon study challenges textbook theories about turbidity currents

12.12.2017 | Earth Sciences

Electromagnetic water cloak eliminates drag and wake

12.12.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>