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Is this [partly] an explanation for how Life got started?

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https://phys.org/news/2017-07-scientists-moon-saturn-chemical-membranes.html

NASA scientists have definitively detected the chemical acrylonitrile in the atmosphere of Saturn's moon Titan, a place that has long intrigued scientists investigating the chemical precursors of life.

On Earth, acrylonitrile, also known as vinyl cyanide, is useful in the manufacture of plastics. Under the harsh conditions of Saturn's largest moon, this chemical is thought to be capable of forming stable, flexible structures similar to cell membranes. Other researchers have previously suggested that acrylonitrile is an ingredient of Titan's atmosphere, but they did not report an unambiguous detection of the chemical in the smorgasbord of organic, or carbon-rich, molecules found there.

Read more at: https://phys.org/news/2017-07-scientists-moon-saturn-chemical-membranes.html#jCp
 

An extract from the article says.....

Quote

 

"Those researchers proposed that acrylonitrile molecules could come together as a sheet of material similar to a cell membrane. The sheet could form a hollow, microscopic sphere that they dubbed an "azotosome." This sphere could serve as a tiny storage and transport container, much like the spheres that lipid bilayers can form".

The ability to form a stable membrane to separate the internal environment from the external one is important because it provides a means to contain chemicals long enough to allow them to interact," said Michael Mumma, director of the Goddard Center for Astrobiology, 

 



Read more at: https://phys.org/news/2017-07-scientists-moon-saturn-chemical-membranes.html#jCp

 

Or am I reading too much into this rather exciting discovery?

Edited by beecee

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The actual research article.......

http://advances.sciencemag.org/content/3/7/e1700022

ALMA detection and astrobiological potential of vinyl cyanide on Titan.

 

 

Abstract

Recent simulations have indicated that vinyl cyanide is the best candidate molecule for the formation of cell membranes/vesicle structures in Titan’s hydrocarbon-rich lakes and seas. Although the existence of vinyl cyanide (C2H3CN) on Titan was previously inferred using Cassini mass spectrometry, a definitive detection has been lacking until now. We report the first spectroscopic detection of vinyl cyanide in Titan’s atmosphere, obtained using archival data from the Atacama Large Millimeter/submillimeter Array (ALMA), collected from February to May 2014. We detect the three strongest rotational lines of C2H3CN in the frequency range of 230 to 232 GHz, each with >4σ confidence. Radiative transfer modeling suggests that most of the C2H3CN emission originates at altitudes of ≳200 km, in agreement with recent photochemical models. The vertical column densities implied by our best-fitting models lie in the range of 3.7 × 1013 to 1.4 × 1014 cm−2. The corresponding production rate of vinyl cyanide and its saturation mole fraction imply the availability of sufficient dissolved material to form ~107 cell membranes/cm3 in Titan’s sea Ligeia Mare.

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To answer the question in the title, absolutely not. Here are two alternative questions with their answers.

If there is life on Titan, could this be part of how it got started? Quite possibly.

If life were to develop on Titan, could this be part of how it would develop? Quite possibly.

There is no evidence that vinyl cyanide, or any of its derivatives were involved in the emergence of life on Earth. The conditions for its formation were very unlikely to be present on the primordial Earth. Even if they were, there is no apparent path to convert a vinyl cyanide membrane to a bilipid one.

What we can say is that if bilipid membrane sacs were central to the emergence of life on Earth then vinyl cyanide membrane sacs could perform, or could already have performed, an analagous role on Titan.

I find the concept of such protocells a compelling one and it is interesting, possibly important, that here is a mechanism to produce similar features in a radically different environment.

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15 hours ago, Area54 said:

To answer the question in the title, absolutely not. Here are two alternative questions with their answers.

If there is life on Titan, could this be part of how it got started? Quite possibly.

If life were to develop on Titan, could this be part of how it would develop? Quite possibly.

There is no evidence that vinyl cyanide, or any of its derivatives were involved in the emergence of life on Earth. The conditions for its formation were very unlikely to be present on the primordial Earth. Even if they were, there is no apparent path to convert a vinyl cyanide membrane to a bilipid one.

What we can say is that if bilipid membrane sacs were central to the emergence of life on Earth then vinyl cyanide membrane sacs could perform, or could already have performed, an analagous role on Titan.

I find the concept of such protocells a compelling one and it is interesting, possibly important, that here is a mechanism to produce similar features in a radically different environment.

OK, biology is not a strong point of mine,[if I have any strong points at all!:P] but I have always been attracted to Panspermia, and I saw the following phrase from the article as supporting that hypothesis...

Quote

The ability to form a stable membrane to separate the internal environment from the external one is important because it provides a means to contain chemicals long enough to allow them to interact,

My reasoning is along the lines that this "stable membrane" would protect the chemical reactions inside [and eventual emergence of life] from environments that maybe harmful to it...eg: depths of inter stellar and inter galactic space, harmful radiation etc.                                                                         
What do you think?
 

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1 hour ago, beecee said:

My reasoning is along the lines that this "stable membrane" would protect the chemical reactions inside [and eventual emergence of life] from environments that maybe harmful to it...eg: depths of inter stellar and inter galactic space, harmful radiation etc.                                                                         
What do you think?

I don't think that flies. There is little reason to expect such a membrane to be stable in interstellar space (quite the reverse). It is stable in a specific portion of the Titan environment. The importance of its stability in that environment is that it provides a locale where a metabolism may develop and possibly evolve. All the panspermia hypotheses I have seen envisage the organisms surviving interstellar space safely embedded within minerals/rocks, or spore like bodies with thick protective coatings, not layers one or two moelcules thick.

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1 hour ago, Area54 said:

I don't think that flies. There is little reason to expect such a membrane to be stable in interstellar space (quite the reverse). It is stable in a specific portion of the Titan environment. The importance of its stability in that environment is that it provides a locale where a metabolism may develop and possibly evolve. All the panspermia hypotheses I have seen envisage the organisms surviving interstellar space safely embedded within minerals/rocks, or spore like bodies with thick protective coatings, not layers one or two moelcules thick.

Panspermia adds another level of difficulty when everything is likely  here on Earth; certainly all the necessary elements.

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The argument on panspermia as a process is different from what we are discussing here, which is whether vinyl cyanide membranes could offer protection in the interstellar medium. They wouldn't.

Everything available on Earth for abiogenesis is not an argument against panspermia. Occam's razor is sometime necessarily blunt. Plus the one thing that may not be available on Earth is sufficient time.

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25 minutes ago, StringJunky said:

Panspermia adds another level of difficulty when everything is likely  here on Earth; certainly all the necessary elements.

 

21 minutes ago, Area54 said:

The argument on panspermia as a process is different from what we are discussing here, which is whether vinyl cyanide membranes could offer protection in the interstellar medium. They wouldn't.

Everything available on Earth for abiogenesis is not an argument against panspermia. Occam's razor is sometime necessarily blunt. Plus the one thing that may not be available on Earth is sufficient time.

Thanks fellas! Like I said, biology/astrobiology is not my forte I'm afraid....thanks for the replies.

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21 minutes ago, Area54 said:

The argument on panspermia as a process is different from what we are discussing here, which is whether vinyl cyanide membranes could offer protection in the interstellar medium. They wouldn't.

Everything available on Earth for abiogenesis is not an argument against panspermia. Occam's razor is sometime necessarily blunt. Plus the one thing that may not be available on Earth is sufficient time.

It's not an argument against panspermia but is an argument against giving it precedence for consideration over earthbound abiogenesis until it's shown it can't be the case or is less likely.

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Shame they can't read genes from fossils. 

My own feeling is that panspermia didn't happen, although there's no reason why it couldn't. I'm just guessing.

The earliest evidence of life is of very basic stuff, and I would have thought that panspermia might have introduced more advanced life as well, giving life on Earth a real kick start of more evolved organisms. 

But there might be good reasons why that couldn't happen I guess.

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I'm sorry, I've only skipped through this thread so this link may have already been presented, interesting though.

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On 04/08/2017 at 2:45 PM, iNow said:

Thanks. I have read of attempts to extract dna from apparently fossilised bones etc. I think though, that it's not strictly a fossil, if you can do that. Even if it's millions of years old, it's dna that hasn't yet fossilised. (ie, hasn't been replaced with minerals) although most people certainly would say it came from a fossil.

I was musing about dna being truly fossilised, but still readable. When you are talking about the very earliest life, about 3.5 billion years ago, there were no bones and teeth, but maybe the dna left some kind of fossil that might one day be readable using techniques that nobody has yet invented.

If that were to happen, you would probably be able to say for sure whether panspermia happened, or life started independently, here on Earth. 

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