Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Using plants against soils contaminated with arsenic

16.11.2010
Two essential genes that control the accumulation and detoxification of arsenic in plant cells have been identified. This discovery is the fruit of an international collaboration involving laboratories in Switzerland, South Korea and the United States, with the participation of members of the National Centre of Competence in Research (NCCR) Plant Survival.

The results presented are a promising basis for reducing the accumulation of arsenic in crops from regions in Asia that are polluted by this toxic metalloid, as well as for the cleanup of soils contaminated by heavy metals. The findings are published this week in the prestigious journal PNAS.

The sinking of tubewells in Southeast Asia as well as mining in regions such as China, Thailand, and the United States, are the cause that arsenic concentrations in water often exceed the World Health Organization (WHO) limit of 10 μg/L, the value above which health problems start to occur. Tens of millions of people are exposed to this risk by drinking contaminated water or by ingesting cereal crops cultivated in polluted soils.

A long lasting exposure to this highly toxic metalloid could affect the gastrointestinal transit, the kidneys, the liver, the lungs, the skin and increases the risk of cancer. In Bangladesh, it is estimated that 25 million people drink water that contains more than 50 μg/L of arsenic and that two million of them risk of dying from cancer caused by this toxic substance.

Plants offer a way for toxic metals to enter the food chain. We know, for example, that arsenic is stored within rice grains, which, in regions polluted with this toxic metalloid, constitutes a danger for the population whose diet depends to a great extent on this cereal.

Arsenic or cadmium in soils is transported to plant cells and stored in compartments called vacuoles. Within the cell, the translocation of arsenic and its storage in vacuoles is ensured by a category of peptides – the phytochelatins – that bind to the toxic metalloid, and are transported into the vacuole for detoxification, similar to hooking up a trailer to a truck. In terms of the process, it is the “truck and trailer” complex that is stored in the vacuole.

“By identifying the genes responsible for the vacuolar phytochelatin transport and storage, we have found the missing link that the scientific community searched for the past 25 years”, explains Enrico Martinoia, a professor in plant physiology at the University of Zurich. The experiments carried out on the model plant Arabidopsis can easily be adapted to other plants such as rice.

Enrico Martinoia is one of the directors of this research that includes the Korean professor Youngsook Lee from the Pohang University of Science and Technology (POSTECH) and Julian Schroeder, biology professor at the University of California, San Diego (UCSD). Along with Stefan Hörtensteiner, also from the University of Zurich, and Doris Rentsch from the University of Bern, he is one of the three members of the NCCR Plant Survival who participated in this study which was published in PNAS.

Controlling these genes will make it possible to develop plants capable of preventing the transfer of toxic metals and metalloids from the roots to the leaves and grains thereby limiting the entry of arsenic into the food chain. “By focusing on these genes, states Youngsook Lee, we could avoid the accumulation of these heavy metals in edible portions of the plant such as grains or fruits.”

At the same time, researchers have discovered a way to produce plants capable of accumulating a greater amount of toxic metals which consequently can be used to clean up contaminated soils. These plants would then be burned in blast furnaces in order to eliminate the toxic elements.

Literature:
Won-Yong Song, Jiyoung Park, David G. Mendoza-Cózatl, Marianne Suter-Grotemeyer, Donghwan Shim, Stefan Hörtensteiner, Markus Geisler, Barbara Weder, Philip A. Rea, Doris Rentsch, Julian I. Schroeder, Youngsook Lee, Enrico Martinoia: Arsenic tolerance in Arabidopsis is mediated by two ABCC-type phytochelatin transporters, in: PNAS, Doi: 10.1073/pnas.1013964107
Contact:
Prof. Enrico Martinoia
University of Zurich
Tel. : +41 44 634 8222
enrico.martinoia@botinst.uzh.ch

Beat Müller | idw
Further information:
http://www.uzh.ch/

More articles from Studies and Analyses:

nachricht Amputees can learn to control a robotic arm with their minds
28.11.2017 | University of Chicago Medical Center

nachricht The importance of biodiversity in forests could increase due to climate change
17.11.2017 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

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...

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

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>