Jul 24, 2015 05:00 AM
(This post was last modified: Jul 24, 2015 05:02 AM by C C.)
http://news.sciencemag.org/biology/2015/...-mcdonalds
EXCERPT: [...] Microbes tough out some inauspicious environments, from searing hot springs to lakes beneath Antarctic ice. [...] Researchers have [...] detected chemical signs of life from about 4 kilometers down. To search for other deeply buried microbes, an international team of researchers drilled [...] into sediments off the northeast coast of Japan. [...] this deep layer is rich in coal.
[...] As the researchers report online today in Science, their analysis showed small numbers of microbes even in the deepest sediments, which came from 2466 meters below the ocean floor. A cubic centimeter of deep-sea sediment contained about 10 to 10,000 microbial cells. In comparison, the same amount of dirt from your backyard would contain billions of microorganisms, Hinrichs says. “There is life, but there is very little life” at these depths, he says.
When the researchers incubated some of the microbes at 40°C and threw in a little coal dust, they detected signs of metabolic activity indicating that microorganisms from these depths are feeding on coal and releasing methane. The study results suggest that “microbial life is present in sediments down to around 2.5 km below the ocean floor,” says co-author Fumio Inagaki [...] the microbes are eating coal and emitting methane [...]
The microbial groups from far below the ocean floor differed from those in shallower layers. To the researchers’ surprise, the deep-sea microbes were more similar to modern microbes that live in forest soil. [...] It is possible that the microbes the team found are the descendants of terrestrial microorganisms that adapted to life under the sea as their home sank below the surface. But it’s also possible that these microorganisms are the same cells that were alive when the habitat began to sink, meaning they are more than 20 million years old.
[...] You’d expect microbes from this exotic environment to be unusual, and the discovery that they are similar to familiar microorganisms is “disconcerting,” she says. “It’s like going to Pluto and seeing McDonald’s.”
EXCERPT: [...] Microbes tough out some inauspicious environments, from searing hot springs to lakes beneath Antarctic ice. [...] Researchers have [...] detected chemical signs of life from about 4 kilometers down. To search for other deeply buried microbes, an international team of researchers drilled [...] into sediments off the northeast coast of Japan. [...] this deep layer is rich in coal.
[...] As the researchers report online today in Science, their analysis showed small numbers of microbes even in the deepest sediments, which came from 2466 meters below the ocean floor. A cubic centimeter of deep-sea sediment contained about 10 to 10,000 microbial cells. In comparison, the same amount of dirt from your backyard would contain billions of microorganisms, Hinrichs says. “There is life, but there is very little life” at these depths, he says.
When the researchers incubated some of the microbes at 40°C and threw in a little coal dust, they detected signs of metabolic activity indicating that microorganisms from these depths are feeding on coal and releasing methane. The study results suggest that “microbial life is present in sediments down to around 2.5 km below the ocean floor,” says co-author Fumio Inagaki [...] the microbes are eating coal and emitting methane [...]
The microbial groups from far below the ocean floor differed from those in shallower layers. To the researchers’ surprise, the deep-sea microbes were more similar to modern microbes that live in forest soil. [...] It is possible that the microbes the team found are the descendants of terrestrial microorganisms that adapted to life under the sea as their home sank below the surface. But it’s also possible that these microorganisms are the same cells that were alive when the habitat began to sink, meaning they are more than 20 million years old.
[...] You’d expect microbes from this exotic environment to be unusual, and the discovery that they are similar to familiar microorganisms is “disconcerting,” she says. “It’s like going to Pluto and seeing McDonald’s.”