Methane is formed under the absence of oxygen by natural biological and physical processes, e.g. in the sea floor. It is a much more powerful greenhouse gas than carbon dioxide. Thanks to the activity of microorganisms this gas is inactivated before it reaches the atmosphere and unfolds its harmful effects on Earth's climate. Researchers from Bremen have now proven that these microorganisms are quite picky about their diet.
All life on Earth is based on carbon and its compounds. Cell components of all creatures contain carbon. The cell can take up this basic structural element via organic matter or builds up its own organic matter from scratch, i.e. carbon dioxide. Researchers termed the first type of cells heterotrophs and the latter autotrophs. All plants, many bacteria and archaea are autotrophs, whereas all animals, including humans, are heterotrophs. The autotrophs form the basis for the life of the heterotrophs and all higher life by taking up inorganic carbon to form organic material.
To keep the cellular systems running all cells need fuel. Methane can be such a fuel. When studying the methane consuming microbes discovered by Bremen scientists more than ten years ago, it was assumed that they take the methane for filling up their energy tanks and use it as a carbon source, i.e., they were thought to be heterotrophs.
Now scientists from MARUM and the Max Planck Institute for Marine Microbiology have shown that this is surprisingly not the case: the methane derived carbon is not used as a carbon source. "Our growth studies clearly show that the labelled carbon in the methane never showed up in the cell material, but experiments with labelled carbon from carbon dioxide did. It was quite surprising," says author Matthias Kellermann. The archaea in the consortia behave as expected for chemoautotrophs. "Archaea and the sulphate reducing bacteria are living closely together in consortia, which grow extremely slowly. And it was only in the newly synthesised cell materia that we could find the answer for the question from where the carbon originates," adds Kai-Uwe Hinrichs, leader of the organic geochemistry group at MARUM.
Co-author Gunter Wegener from the Max Planck Institute concludes: "With our new knowledge we can optimise our studies about the inactivation of methane in nature. Our surprising results tell us that we still know very few details of this globally important process."
Samples were retrieved from the Guaymas Basin on the West coast of Mexico from a depth of more the 2000 metres using the US diving submersible Alvin.
Matthias Y. Kellermann, Gunter Wegener, Marcus Elvert, Marcos Yukio Yoshinaga, Yu-Shih Lin, Thomas Holler, Xavier Prieto Mollar, Katrin Knittel, and Kai-Uwe Hinrichs Autotrophy as a predominant mode of carbon fixation in anaerobic methane-oxidizing microbial communities PNAS doi/10.1073/pnas.1208795109
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Pigs ‘edited’ with a warthog gene to resist African swine fever could help spawn GM animal farms in the UK
Mouse House to make naturalist biopic, six years after box-office failure of Creation, starring Paul Bettany
International team spends 10 years making inroads into treatment of bacterium which kills up to half of those it infects
You may not know it, but you probably have some Neanderthal in you. For people around the world, except sub-Saharan Africans, about 1 to 3 percent of their DNA comes from Neanderthals, our close cousins who disappeared roughly 39,000 years ago.
Research at Yale plotted what happened in the brains of two scientists as they held a conversation
From medicines to jet fuel, we have so many reasons to celebrate the microbes we live with every day
Genome sequencing indicates Kennewick Man is Native American, reopening the bitter battle over whether he should be reburied or studied
In the article on the discovery of dinosaurs (They’re back, Review, 6 June) you state: “In Sussex, a local doctor uncovered fragmentary remains of what appeared to be two more species of colossal extinct land reptiles.” You grossly underplay the contribution of Lewes-born Gideon Mantell, geologist and palaeontologist, author and diarist, friend to princes and international scholars as well as local doctor. Mantell not only discovered (aided by his wife) the first remains of the iguanodon in 1824 but named it – as it resembled the tooth of an iguana. This was the first known land dinosaur, Mary Anning having identified the first sea-living dinosaur.Mantell went on to put together more pieces of the jigsaw with extra fossil discoveries. In contrast to Richard Owen, whose models form the basis for the Crystal Palace dinosaurs, Mantell stated correctly that iguanodon would have walked on their back legs, using their forearms to fight or gather food. He did, however, attribute the thumb spike to a nose horn though later corrected this assumption. The Natural History Museum has a display on Gideon and his wife Mary’s contribution as well as the large “Mantell-piece” of Iguanodon fossils that he had on show in his museum in Brighton. He sold it, along with many more priceless items, to the British Museum in 1838. Gideon Mantell’s reputation deserves better than your throwaway remark. Debby MatthewsLewes, East Sussex Continue reading...
Unique triangular hairs help keep Saharan silver ants cool at 70°C by manipulating the physics of light
Most animals wouldn't confront a fearsome predator like a lion. But through sophisticated group work, hyenas launch successful raids