Scientists have designed an artificial cell capable to be the basis for life on other planets. Saturn’s moon Titan, with its methane seas – the perfect place for such a life.
Whether on other planets and their moons harbor life? The answer to this question is directly related to another fundamental question: can this life be different, not like on the earth? Usually, talking about extraterrestrial life, astrobiologists say about exoplanets, with conditions similar to earth. In search of small rocky planets orbiting in the so-called habitable zones, scientists, in fact, trying to find a second Earth, where at least there should be a liquid water.
«Follow the water” – this is a principle that has been adopted by those who dream of a future with new astronomical instruments to detect habitable worlds.
But could there be life on earth is not similar conditions? For example, on Titan – Saturn’s icy, where instead of water present liquid hydrocarbons methane and ethane, and poisonous atmosphere there is no water? Can there be unusual for us life forms based on the cleavage of organic molecules that are abundant there on such planets and their satellites?
Experts in molecular dynamics under the leadership Palette Clancy and James Stevenson from Cornell University have positive answers to these questions. They created a theoretical model, which suggests that some forms of life that feed on methane can exist without oxygen in similar conditions Titan.
In an article published in the journal Science Advances , the authors focused on the possibility of creating a cell membrane, “consisting of small nitrogenous structures and capable of operating at temperatures of -292 degrees Fahrenheit (-180 ° C. -« Times “).”
It is known that cells of living organisms on Earth have membranes that are based on containing water molecules cells, and these in turn form a double phospholipid layer. Cell membranes are necessary attribute cells keeping them within the organic substance and while remaining permeable barrier. Titan, as is known, there are no water molecules for the construction of such cells. “We are not biologists, astronomers did not, but we have the right tools. Maybe this will help, since we do not use any prejudice about what should or should not be membrane. We only work with those structures, about who knew what they were there “- explained Palette Clancy, director of work.
It was attended by Jonathan Lunine, a member of the mission “The Cassini-Huygens mission”, an expert on moons of Saturn, discovered a few years ago methane-ethane sea on Titan. Inspired by the idea of the existence of life on Titan hydrocarbon, received a grant to study, he found like-minded people for a life simulation, created not on the basis of water.
The scientists were able to simulate an ideal cell, which is able to perform the essential functions inherent in life – to support metabolism and share.
to distinguish it from normal cells is that it consists of nitrogen, carbon and hydrogen molecules, which are abundant in the seas of Titan have. Chemical molecular configuration thus given cell stability and flexibility, as the cells of terrestrial life forms.
An unusual cell membrane, researchers gave the name “azotosoma.” In the simulation cell researchers used a method that sorts by methane-based structure for the best capacity for organization similar to the membrane film. The best candidates were akrilonikrila molecule, showing stability, resistance to degradation and flexibility comparable to that of phospholipid membranes of cells of the earth.
In the industry akrilonikrily – colorless, poisonous liquid organic structures that are used in the production of acrylic fibers, rubber and thermoplastics. Scientists know that these molecules present in the atmosphere of Titan. Their next step – to understand how the cells based on these molecules can behave in methane seas and the atmosphere of Titan.
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