Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cellular contamination pathway for plutonium, other heavy elements, identified

27.08.2015

Berkeley Lab scientists find that an iron-binding protein can transport actinides into cells

Scientists at Lawrence Berkeley National Laboratory (Berkeley Lab) have reported a major advance in understanding the biological chemistry of radioactive metals, opening up new avenues of research into strategies for remedial action in the event of possible human exposure to nuclear contaminants.


Crystals formed with the protein siderocalin and curium complexes exhibit bright red luminescence when exposed to UV light.

Credit: Lawrence Berkeley National Laboratory

Research led by Berkeley Lab's Rebecca Abergel, working with the Fred Hutchinson Cancer Research Center in Seattle, has found that plutonium, americium, and other actinides can be transported into cells by an antibacterial protein called siderocalin, which is normally involved in sequestering iron.

Their results were published online recently in the journal Proceedings of the National Academy of Sciences in a paper titled, "Siderocalin-mediated recognition, sensitization, and cellular uptake of actinides." The paper contains several other findings and achievements, including characterization of the first ever protein structures containing transuranic elements and how use of the protein can sensitize the metal's luminescence, which could lead to potential medical and industrial applications.

Abergel's group has already developed a compound to sequester actinides and expel them from the body. They have put it in a pill form that can be taken orally, a necessity in the event of radiation exposure amongst a large population. Last year the FDA approved a clinical trial to test the safety of the drug, and they are seeking funding for the tests.

However, a basic understanding of how actinides act in the body was still not well known. "Although [actinides] are known to rapidly circulate and deposit into major organs such as bone, liver, or kidney after contamination, the specific molecular mechanisms associated with mammalian uptake of these toxic heavy elements remain largely unexplored," Abergel and her co-authors wrote.

The current research described in PNAS identifies a new pathway for the intracellular delivery of the radioactive toxic metal ions, and thus a possible new target for treatment strategies. The scientists used cultured kidney cells to demonstrate the role of siderocalin in facilitating the uptake of the metal ions in cells.

"We showed that this protein is capable of transporting plutonium inside cells," she said. "So this could help us develop other strategies to counteract actinide exposure. Instead of binding and expelling radionuclides from the body, we could maybe block the uptake."

The team used crystallography to characterize siderocalin-transuranic actinide complexes, gaining unprecedented insights into the biological coordination of heavy radioelements. The work was performed at the Advanced Light Source (ALS), a Department of Energy synchrotron located at Berkeley Lab.

"These are the first protein structures containing thorium or the transuranic elements plutonium, americium, or curium," Abergel said. "Until this work there was no structure in the Protein Data Bank that had those elements. That's an exciting thing for us."

The researchers also made the unexpected finding that siderocalin can act as a "synergistic antenna" that sensitizes the luminescence of actinides and lanthanides. "We showed that by adding the protein we enhance the sensitization pathways, making it much brighter," Abergel said. "That is a new mechanism that hasn't been explored yet and could be very useful; it could have applications down the line for diagnostics and bioimaging."

Abergel notes that a study like this would have been possible in very few other places. "Very few people have the capabilities to combine the different approaches and techniques--the spectroscopy techniques at the ALS, handling of heavy elements that are radioactive, plus the chemical and biological tools we have onsite," she said. "The combination of all those techniques here is very unique."

###

The work was funded by the Department of Energy's Basic Energy Sciences program in the Office of Science and the National Institutes of Health. The paper's co-authors are Benjamin Allred, Stacey Gauny, Dahlia An, Corie Ralston, and Manuel Sturzbecher-Hoehne of Berkeley Lab, and Roland Strong and Peter Rupert of the Hutchinson Center.

Lawrence Berkeley National Laboratory addresses the world's most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab's scientific expertise has been recognized with 13 Nobel prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy's Office of Science. For more, visit http://www.lbl.gov.

DOE's Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.

Media Contact

Julie Chao
jhchao@lbl.gov
510-486-6491

 @BerkeleyLab

http://www.lbl.gov 

Julie Chao | EurekAlert!

Further reports about: Cellular Energy contamination siderocalin strategies structures uptake

More articles from Life Sciences:

nachricht World’s Largest Study on Allergic Rhinitis Reveals new Risk Genes
17.07.2018 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Plant mothers talk to their embryos via the hormone auxin
17.07.2018 | Institute of Science and Technology Austria

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Microscopic trampoline may help create networks of quantum computers

17.07.2018 | Information Technology

In borophene, boundaries are no barrier

17.07.2018 | Materials Sciences

The role of Sodium for the Enhancement of Solar Cells

17.07.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>