Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Quantum mechanical calculations reveal the hidden states of enzyme active sites

21.11.2014

Enzymes carry out fundamental biological processes such as photosynthesis, nitrogen fixation and respiration, with the help of clusters of metal atoms as "active" sites.

But scientists lack basic information about their function because the states thought to be critical to their chemical abilities cannot be experimentally observed.


This is an image of a [2Fe-2S] cluster

Credit: C. Todd Reichart

Now, researchers at Princeton University have reported the first direct observation of the electronic states of iron-sulfur clusters, common to many enzyme active sites. Published on August 31 in the journal Nature Chemistry, the states were revealed by computing the complicated quantum mechanical behavior of the electrons in the clusters.

"These complexes were thought of as impossible to model, due to the complexity of the quantum mechanics," said Garnet Chan, the A. Barton Hepburn Professor of Chemistry and corresponding author on the paper.

In these systems, the electrons interact strongly with each other, their movements resembling a complicated dance. To reduce the complexity, the researchers drew on a new understanding, gained from fundamental work in quantum information theory, that the motion of the electrons had a special pattern.

"At first glance, the electrons appear to move in a complicated way, but eventually you realize that they only care about what their immediate neighbors are doing, similar to being in a crowded room. This restriction on their behavior leads to important simplifications: the calculations become very difficult rather than impossible -- it's just on the edge of what can be done," Chan said.

Using their new method, Chan and coworkers found that iron-sulfur clusters possess an order of magnitude more accessible electronic states than previously reported. The researchers suggested that this unusual richness might explain their ubiquity in biological processes.

This finding, that there are many more available electronic states than previously thought, presents many different chemical possibilities. What if these clusters simultaneously used a combination of mechanisms, instead of the accepted chemical idea that there is one distinct electronic pathway, Chan wondered. To test that idea and learn more about the clusters' behavior, the researchers plan to extend their calculations to observe a chemical transformation in action.

"If you want to understand why iron-sulfur clusters are a ubiquitous biological motif and how we can create even better synthetic analogs, then you need to know what the electrons are doing," Chan said. "Now we've caught a first glimpse as to what they are getting up to."

Read the full article here:

Sharma, S.; Sivalingam, K.; Neese, F.; Chan, K.-L. G. "Low-energy spectrum of iron sulfur clusters directly from many-particle quantum mechanics." Nat. Chem. 2014, 6, 927.

This work was supported by the US National Science Foundation (CHE-1265277) and used software developed with the support of OCI-1265278. F.N. and K.S acknowledge financial support from the Max Planck Society, the University of Bonn and the SFB 813 "Chemistry at Spin Centers."

Tien Nguyen | EurekAlert!
Further information:
http://www.princeton.edu/

More articles from Life Sciences:

nachricht Making fuel out of thick air
08.12.2017 | DOE/Argonne National Laboratory

nachricht ‘Spying’ on the hidden geometry of complex networks through machine intelligence
08.12.2017 | Technische Universität Dresden

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

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...

Im Focus: Virtual Reality for Bacteria

An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications

Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...

Im Focus: A space-time sensor for light-matter interactions

Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.

The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...

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

Midwife and signpost for photons

11.12.2017 | Physics and Astronomy

How do megacities impact coastal seas? Searching for evidence in Chinese marginal seas

11.12.2017 | Earth Sciences

PhoxTroT: Optical Interconnect Technologies Revolutionized Data Centers and HPC Systems

11.12.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>