On board the vessel Vædderen during the Galathea 3 expedition, Professor of Geomicrobiology Bo Barker Jørgensen (left) and Professor of Microbial Ecology Lars Peter Nielsen (right) check a mud core for thread-forming bacteria. Now they are back in the same boat. They have both received an Advanced Grant from the European Research Council for research into the ecosystems on the sea bed. It is highly unusual for two colleagues with such closely related projects to receive the prestigious grant at the same time. Photo: Esben Nielsen

The life of microorganisms in the muddy world on the sea bed is hidden to the naked eye. There is nevertheless plenty of it. The European Research Council has just allocated two giant research grants to two professors from the Department of Bioscience, Aarhus University, who will investigate the microbiology of the sea bed, each in their own way.

2012.01.25 | Camilla Nissen Toftdal, Center for Geomikrobiologi

With a steady hand, Professor Nielsen extracts samples of the microbial electrical network from the mud in the marina. Later, he will have to go out and explore the world to determine how widespread the electrical networks are and whether they have different characteristics. Photo: Camilla Nissen Toftdal

The researchers need both safety helmet and elbow grease when extracting samples from the deep biosphere, which is what the bottom layers of the sea bed are called. This is where the majority of the Earth’s microorganisms live and it is the ecosystem Professor Jørgensen and his team of researchers are going to study. Photo: Nils Risgaard-Petersen

Thirty years ago, they sat opposite each other in their Icelandic sweaters, discussing strange thread-forming sulphur bacteria. Associate Professor Bo Barker Jørgensen managed to convince the young biology student Lars Peter Nielsen that his thesis should be about the microbial ecology of the sea bed rather than weeds. And that is what happened. Today, they are both professors and can celebrate that the European Research Council (ERC) has granted each of them an Advanced Grant. Professor Jørgensen, director of the Danish National Research Foundation’s Centre for Geomicrobiology, will study the deepest layers of the sea bed, where there is very limited energy available for microorganisms, and where life therefore takes place in slow motion. Professor Nielsen will begin at the other end of the energy scale in the upper sediments of the sea bed, where he has discovered an electrical world created by the bacteria themselves.

The electrical world of nature

All energy processes in the world of biology involve the movement of electrons from one substance to another. It was always believed that the substances had to be next to each other for this to happen. However, about 18 months ago, Professor Nielsen discovered that biology has found a way of creating power lines permitting the exchange of electrons between organisms over large distances.

“We discovered that electrical currents are running through the sea bed, connecting organisms and processes over vast distances. We will use the grant from the ERC to study these electrical circuits and how they spread. We already know that they must be controlled by the microorganisms and, thanks to a generous grant from the Danish Council for Independent Research, we can also study their origin and metabolism,” Professor Nielsen explains.

Life in the slow lane

Professor Nielsen will begin with the top layers of the sea bed, where fresh organic material is constantly being deposited, and where rapid decomposition takes place. Professor Jørgensen will dig much deeper into the mud to the millions-of-years-old sediments where the microorganisms are close to starvation and barely propagate. Here life is so different that the researchers cannot use standard microbiological methods in their work.
“We’re going to study the largest ecosystem on Earth, where the majority of microorganisms live. Researchers still don’t know the main microorganisms, what processes they carry out and what energy sources they have available,” Professor Jørgensen says.

Daring and wild ideas

Both Professor Nielsen and Professor Jørgensen work with nature in areas that have real surprises in store, such as an electrical network that grows out of the wet environment. A world without light or oxygen, almost without nutrition and under enormous pressure, but nevertheless full of microbial life. The ERC’s assessment panel describes Professor Nielsen as an ‘extremely creative researcher’, and Professor Jørgensen is a pioneer in the work with the deep biosphere. Both refer to themselves as explorers. In fact, Professor Nielsen has used an acronym for his project – ‘COULOMBUS’. In this way, he has named it after both the French physicist C. A. Coulomb, who gave his name to the unit used to describe an electrical charge, and the Spanish explorer Christopher Columbus. Just like the Spanish royal couple, the ERC has the courage to support individuals with wild ideas. As Professor Nielsen expresses it: “Once the ERC believes in a man and his idea, it’s full speed ahead.”

Contact

Professor Bo Barker Jørgensen, Director of the Centre for Geomicrobiology, Department of Bioscience, +45 8942 3314/+45 2010 2123, bo.barker@biology.au.dk

Professor Lars Peter Nielsen, Microbiology, Department of Bioscience, +45 8942 3250/+45 6020 2654, lars.peter.nielsen@biology.au.dk

Aarhus University at the forefront

Aarhus University has received more than 38% of the ERC Grants awarded to Denmark, which makes it the Danish university with the most ERC Grants. Read more (in Danish only).