(Press-News.org) Scientists at the Max Planck Institute for Chemical Energy Conversion (MPI CEC) and the Ruhr-Universität Bochum (RUB) have found through spectroscopic investigations on a hydrogen-producing enzyme that the environment of the catalytic site acts as an electron reservoir in the enzyme. Thus, it can very efficiently produce hydrogen, which has great potential as a renewable energy source. The research team describes their results in the journal "Angewandte Chemie".
Producing hydrogen with enzymes
The system analysed constitutes an enzyme that catalyses the formation and conversion of hydrogen. In its centre it has a double-iron core, and is therefore also called [FeFe] hydrogenase. Hydrogenases are of great interest for energy research, since they can efficiently produce hydrogen. However, new catalysts can only be developed given a deep understanding of their mode of action.
Electron transfer in several steps
In hydrogen production, two electrons get together with two protons. The research team showed that, as expected, the first electron is initially transferred to the iron centre of the enzyme. The second transfer on the other hand is to an iron-sulphur cluster that is located in the periphery. It thus forms a temporary storage for the second electron. This "super-reduced" state may be responsible for the extremely high efficiency of the hydrogenase. Subsequently both electrons are transferred in one step from the enzyme to the protons, so that hydrogen is generated. "Only the use of two different spectroscopic techniques made the discovery possible", says Agnieszka Adamska, a doctoral student at MPI CEC who carried out the spectroscopic studies.
10,000 molecules of hydrogen per second
"Up to 10,000 molecules of hydrogen per second can be generated by a single [FeFe] centre", says Camilla Lambertz, a postdoc at the RUB who prepared the biological samples for the project. The enzyme is thus among the most efficient hydrogenases and is therefore also being intensively investigated by biologists and chemists with a view to achieving environmentally friendly hydrogen production. The complete mechanism of hydrogen formation is, however, complex and several steps need to be clarified. Next, the researchers at MPI CEC and the Ruhr-Universität Bochum aim to use sensitive spectroscopic methods to locate the proton to which the two electrons are transferred. This negatively charged hydrogen atom (hydride) reacts with another proton to form hydrogen. Inspired by the [FeFe] hydrogenase, the researchers would like to develop their own hydrogen-producing catalysts that could be used for the generation of hydrogen.
###
Bibliographic record
A. Adamska, A. Silakov, C. Lambertz, O. Rüdiger, T. Happe, E. Reijerse, W. Lubitz (2012): Identification and Characterization of the "Super-Reduced" State of the H-Cluster in [FeFe] Hydrogenase: A New Building Block for the Catalytic Cycle?, Angewandte Chemie International Edition, doi: 10.1002/anie.201204800
Further information
Dr. Rebekka Loschen, Max Planck Institute for Chemical Energy Conversion,
Public Relations, 45470 Mülheim a.d.Ruhr, +49/208/3063681
rebekka.loschen@cec.mpg.de
Dr. Camilla Lambertz, Photo Biotechnology Work Group, Faculty of Biology and Biotechnology at the Ruhr-Universität, 44780 Bochum, Tel. +49/234/32-24496
camilla.lambertz@rub.de
Editor: Dr. Rebekka Loschen, MPI END
Temporary storage for electrons: Natural method of producing hydrogen
Researchers from the RUB and MPI Mülheim report in “Angewandte Chemie”
2012-11-02
ELSE PRESS RELEASES FROM THIS DATE:
Health project in India saved many mothers and children
2012-11-02
Infant mortality has fallen by half, and the number of women who died from complications during pregnancy and childbirth by three-quarters. This is the result of a four-year health care project in one of India's poorest districts.
"We're overjoyed that mortality could be reduced with relatively simple means like mobile health care centres. It was successful because pregnant women and new mothers got the opportunity to actively seek care."
So says Siw Alehagen who, together with AnnaKarin Johansson, Orvar Finnström and Göran Hermansson – all of Linköping University ...
MRI research sheds new light on nerve fibers in the brain
2012-11-02
World-leading experts in Magnetic Resonance Imaging from The University of Nottingham's Sir Peter Mansfield Magnetic Resonance Centre have made a key discovery which could give the medical world a new tool for the improved diagnosis and monitoring of brain diseases like multiple sclerosis.
The new study, published in the Proceedings of the National Academy of Science, reveals why images of the brain produced using the latest MRI techniques are so sensitive to the direction in which nerve fibres run.
The white matter of the brain is made up of billions of microscopic ...
New finding gives clues for overcoming tamoxifen-resistant breast cancer
2012-11-02
CINCINNATI—A University of Cincinnati (UC) cancer biology team reports breakthrough findings about specific cellular mechanisms that may help overcome endocrine (hormone) therapy-resistance in patients with estrogen-positive breast cancers, combating a widespread problem in effective medical management of the disease.
Xiaoting Zhang, PhD, and his colleagues have identified a specific estrogen receptor co-activator—known as MED1—as playing a central role in mediating tamoxifen resistance in human breast cancer. The team reports its findings in the Nov. 1, 2012, issue of ...
Active surveillance can reduce suffering among men with prostate cancer
2012-11-02
With active surveillance many men with prostate cancer could dispense with radiation treatment and surgery, and thus avoid adverse effects such as incontinence and impotence. This is the outcome of a study of almost 1,000 men diagnosed with prostate cancer conducted at Sahlgrenska Academy, University of Gothenburg, Sweden.
The introduction of PSA tests, which are used to screen for prostate cancer, offers early tumour detection, reducing mortality rates. At the same time, prostate cancer is in many cases a slow-growing form of cancer. Many men may never develop symptoms ...
Don't ignore doubts about marriage, researcher warns
2012-11-02
Couples about to tie the knot shouldn't ignore nagging doubts about getting married, warns a University of Alberta researcher.
"If you are having doubts about the relationship, just ignoring them may make a difference years down the road," said Matthew Johnson who co-authored the study while at Kansas State University. Johnson is now an assistant professor in the University of Alberta Department of Human Ecology.
The study, published recently in the journal Family Process, found that couples who were more confident as they exchanged vows also spent more time together ...
Cannabis use mimics cognitive weakness that can lead to schizophrenia
2012-11-02
Researchers at the University of Bergen in Norway have found new support for their theory that cannabis use causes a temporary cognitive breakdown in non-psychotic individuals, leading to long-term psychosis. In an fMRI study published this week in Frontiers in Psychiatry, researchers found a different brain activity pattern in schizophrenia patients with previous cannabis use than in schizophrenic patients without prior cannabis use.
The results reinforce the researchers' model where cannabis users suffering from schizophrenia actually may have higher cognitive abilities ...
World record for the entanglement of twisted light quanta
2012-11-02
To this end, the researchers developed a new method for entangling single photons which gyrate in opposite directions. This result is a first step towards entangling and twisting even macroscopic, spatially separated objects in two different directions. The researchers at the Vienna Center for Quantum Science and Technology (VCQ), situated at the University of Vienna, and the Institute for Quantum Optics and Quantum Information (IQOQI) at the Austrian Academy of Sciences have were able to get their pioneering results published in the current issue of the renowned scientific ...
Grading US presidents on the economy
2012-11-02
During presidential campaigns, it's not unusual to hear candidates from both parties say they will focus on strengthening the nation's economy. But how well have presidents delivered on that promise once in the White House?
On a newly-released report card that grades presidents on their economic performance, Franklin D. Roosevelt, Warren G. Harding and Rutherford B. Hayes are at the top of the class, while Chester Arthur, Herbert Hoover and Martin Van Buren receive failing grades.
The first-of-its-kind study by the Georgia Institute of Technology analyzed up to 220 ...
Cancer bound
2012-11-02
A person doesn't have to go far to find a polycyclic aromatic hydrocarbon (PAH). These carcinogen precursors are inhaled through automobiles exhaust during the morning commute, are present in a drag of cigarette smoke, and are part of any barbequed meal.
Once ingested or inhaled, these big, bulky multi-ringed molecules are converted into reactive carcinogenic compounds that can bind to DNA, sometimes literally bending the double helix out of its normal shape, to form areas of damage called lesions. The damaged DNA can create errors in the genetic code during replication, ...
Navy researchers look to rotating detonation engines to power the future
2012-11-02
WASHINGTON--With its strong dependence on gas-turbine engines for propulsion, the U.S. Navy is always looking for ways to improve the fuel consumption of these engines. At the Naval Research Laboratory (NRL), scientists are studying the complex physics of Rotating Detonation Engines (RDEs) which offer the potential for high dollar savings by way of reduced fuel consumption in gas-turbine engines, explains Dr. Kazhikathra Kailasanath, who heads NRL's Laboratories for Computational Physics and Fluid Dynamics.
Many Navy aircraft use gas-turbine engines for propulsion, with ...
LAST 30 PRESS RELEASES:
One-third of young people are violent toward their parents
New SEOULTECH study reveals transparent windows that shield buildings from powerful electromagnetic pulses
Randomized trial finds drug therapy reduces hot flashes during prostate cancer treatment
Reshaping gold leads to new electronic and optical properties
Tracker to help manage Long COVID energy levels created by researchers
Using generative AI to help scientists synthesize complex materials
Unexpected feedback in the climate system
Fresh insights show how cancer gene mutations drive tumor growth
Unexpected climate feedback links Antarctic ice sheet with reduced carbon uptake
Psychosis rates increasing in more recent generations
Tiny new dinosaur Foskeia pelendonum reshapes the dinosaur family tree
New discovery sheds light on evolutionary crossroads of vertebrates
Aortic hemiarch reconstruction safely matches complex aortic arch reconstruction for acute dissection in older adults
Destination Earth digital twin to improve AI climate and weather predictions
Late-breaking study finds comparable long-term survival between two leading multi-arterial CABG strategies
Lymph node examination should be expanded to accurately assess cancer spread in patients with lung cancer
Study examines prediction of surgical risk in growing population of adults with congenital heart disease
Novel radiation therapy QA method: Monte Carlo simulation meets deep learning for fast, accurate epid transmission dose generation
A 100-fold leap into the unknown: a new search for muonium conversion into antimuonium
A new approach to chiral α-amino acid synthesis - photo-driven nitrogen heterocyclic carbene catalyzed highly enantioselective radical α-amino esterification
Physics-defying discovery sheds new light on how cells move
Institute for Data Science in Oncology announces new focus-area lead for advancing data science to reduce public cancer burden
Mapping the urban breath
Waste neem seeds become high-performance heat batteries for clean energy storage
Scientists map the “physical genome” of biochar to guide next generation carbon materials
Mobile ‘endoscopy on wheels’ brings lifesaving GI care to rural South Africa
Taming tumor chaos: Brown University Health researchers uncover key to improving glioblastoma treatment
Researchers enable microorganisms to build molecules with light
Laws to keep guns away from distressed individuals reduce suicides
Study shows how local business benefits from city services
[Press-News.org] Temporary storage for electrons: Natural method of producing hydrogenResearchers from the RUB and MPI Mülheim report in “Angewandte Chemie”