Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Hydrogen highway in the deep sea

11.08.2011
Max Planck Researchers discover hydrogen-powered symbiotic bacteria in deep-sea hydrothermal vent mussels

The search for new energy sources to power mankind’s increasing needs is currently a topic of immense interest. Hydrogen-powered fuel cells are considered one of the most promising clean energy alternatives. While intensive research efforts have gone into developing ways to harness hydrogen energy to fuel our everyday lives, a natural example of a living hydrogen-powered ‘fuel cell’ has gone unnoticed.


At the Black Smokers in 3000 meter depth there live exceptional symbiotic communities.
Marum


The mussel beds at hydrothermal vents form a teeming expanse that contains an estimated half a million mussels.
Marum

During a recent expedition to hydrothermal vents in the deep sea, researchers from the Max Planck Institute of Marine Microbiology and the Cluster of Excellence MARUM discovered mussels that have their own on-board ‘fuel cells’, in the form of symbiotic bacteria that use hydrogen as an energy source. Their results, which appear in the current issue of Nature, suggest that the ability to use hydrogen as a source of energy is widespread in hydrothermal vent symbioses.

Deep-sea hydrothermal vents are formed at mid-ocean spreading centers where tectonic plates drift apart and new oceanic crust is created by magma rising from deep within the Earth. When seawater interacts with hot rock and rising magma, it becomes superheated, dissolving minerals out of the Earth’s crust. At hydrothermal vents, this superheated energy-laden seawater gushes back out into the ocean at temperatures of up to 400 degrees Celsius, forming black smoker chimneys where it comes into contact with cold deep-sea water. These hot fluids deliver inorganic compounds such as hydrogen sulfide, ammonium, methane, iron and hydrogen to the oceans. The organisms living at hydrothermal vents oxidize these inorganic compounds to gain the energy needed to create organic matter from carbon dioxide. Unlike on land, where sunlight provides the energy for photosynthesis, in the dark depths of the sea, inorganic chemicals provide energy for life in a process called chemosynthesis.

When hydrothermal vents were first discovered more than 30 years ago, researchers were astounded to find that they were inhabited by lush communities of animals such as worms, mollusks and crustaceans, most of which were completely unknown to science. The first to investigate these animals quickly realized that the key to their survival was their symbiotic association with chemosynthetic microbes, which are the on-board power plants for hydrothermal vent animals. Until now, only two sources of energy were known to power chemosynthesis by symbiotic bacteria at hydrothermal vents: Hydrogen sulfide, used by sulfur-oxidizing symbionts, and methane, used by methane-oxidizing symbionts. “We have now discovered a third energy source” says Nicole Dubilier from the Max Planck Institute of Marine Microbiology in Bremen, who led the team responsible for this discovery.

The discovery began at the Logatchev hydrothermal vent field, at 3000 m depth on the Mid-Atlantic Ridge, an undersea mountain range halfway between the Caribbean and the Cape Verde Islands. The highest hydrogen concentrations ever measured at hydrothermal vents were recorded during a series of research expeditions to Logatchev. According to Jillian Petersen, a researcher with Nicole Dubilier, “our calculations show that at this hydrothermal vent, hydrogen oxidation could deliver seven times more energy than methane oxidation, and up to 18 times more energy than sulfide oxidation”.

In the gills of the deep-sea mussel Bathymodiolus puteoserpentis, one of the most abundant animals at Logatchev, the researchers discovered a sulfur-oxidizing symbiont that can also use hydrogen as an energy source. To track down these hydrogen-powered on-board ‘fuel cells’ in the deep-sea mussels, the researchers deployed two deep-sea submersibles, MARUM-QUEST from MARUM at the University of Bremen, and KIEL 6000 from IFM-GEOMAR in Kiel. With the help of these remotely-driven submersibles, they sampled mussels from sites kilometers below the sea surface. Their ship-board experiments with live samples showed that the mussels consumed hydrogen. Once the samples were back in the laboratory on land, they were able to identify the mussel symbiont hydrogenase, the key enzyme for hydrogen oxidation, using molecular techniques.

The mussel beds at Logatchev form a teeming expanse that covers hundreds of square meter and contains an estimated half a million mussels. “Our experiments show that this mussel population could consume up to 5000 liters of hydrogen per hour” according to Frank Zielinski, a former doctoral student in Nicole Dubilier’s Group in Bremen, who now works as a post-doctoral researcher at the Helmholtz Centre for Environmental Research in Leipzig. The deep-sea mussel symbionts therefore play a substantial role as the primary producers responsible for transforming geofuels to biomass in these habitats. “The hydrothermal vents along the mid-ocean ridges that emit large amounts of hydrogen can therefore be likened to a hydrogen highway with fuelling stations for symbiotic primary production” says Jillian Petersen.

Even the symbionts of other hydrothermal vent animals such as the giant tubeworm Riftia pachyptila and the shrimp Rimicaris exoculata have the key gene for hydrogen oxidation, but remarkably, this had not been previously recognized. “The ability to use hydrogen as an energy source seems to be widespread in these symbioses, even at hydrothermal vent sites with low amounts of hydrogen” says Nicole Dubilier.

This study was supported by the Max Planck Society, the German Research Foundation (Priority program 1144: “From Mantle to Ocean: Energy-, Material- and Life Cycles at Spreading Axes’’), and the Cluster of Excellence “The Ocean in the Earth System” at MARUM, Bremen.

Publication reference

Jillian M. Petersen, Frank U. Zielinski, Thomas Pape, Richard Seifert, Cristina Moraru, Rudolf Amann, Stephane Hourdez, Peter R. Girguis, Scott D. Wankel, Valerie Barbe, Eric Pelletier, Dennis Fink, Christian Borowski, Wolfgang Bach, Nicole Dubilier
Hydrogen is an energy source for hydrothermal vent symbioses
Nature 474, 11 August 2011. doi: 10.1038/nature10325
Contact
Dr. Nicole Dubilier
Max Planck Institute for Marine Microbiology, Bremen
Phone: +49 421 2028-932
Fax: +49 421 2028-580
Email: ndubilie@mpi-bremen.de
Dr. Jillian Petersen
Max Planck Institute for Marine Microbiology, Bremen
Phone: +49 421 2028-906
Email: jmpeters@mpi-bremen.de
Dr. Frank Zielinski
Helmholtz-Zentrum für Umweltforschung (UFZ)
Phone: +49 341 235-1373

Barbara Abrell | Max-Planck-Institut
Further information:
http://www.mpg.de/
http://www.mpg.de/790458/W003_Biology-Medicine_062-069.pdf

More articles from Earth Sciences:

nachricht World’s oldest known oxygen oasis discovered
18.01.2018 | Eberhard Karls Universität Tübingen

nachricht A close-up look at an uncommon underwater eruption
11.01.2018 | Woods Hole Oceanographic Institution

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | 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

 
Latest News

Let the good tubes roll

19.01.2018 | Materials Sciences

How cancer metastasis happens: Researchers reveal a key mechanism

19.01.2018 | Health and Medicine

Meteoritic stardust unlocks timing of supernova dust formation

19.01.2018 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>