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Switch to Forum Live View Researchers may have solved origin-of-life conundrum
3 years ago  ::  Mar 17, 2015 - 10:21AM #1
MMarcoe
Posts: 20,907

Scientists doing some of that "historical science" and wasting our time with their "speculation"! They worked backward to find a route to RNA from simpler chemicals. They succeeded.



So much for those "odds."


 


Researchers may have solved origin-of-life conundrum




The origin of life on Earth is a set of paradoxes. In order for life to have gotten started, there must have been a genetic molecule—something like DNA or RNA—capable of passing along blueprints for making proteins, the workhorse molecules of life. But modern cells can’t copy DNA and RNA without the help of proteins themselves. To make matters more vexing, none of these molecules can do their jobs without fatty lipids, which provide the membranes that cells need to hold their contents inside. And in yet another chicken-and-egg complication, protein-based enzymes (encoded by genetic molecules) are needed to synthesize lipids.


Now, researchers say they may have solved these paradoxes. Chemists report today that a pair of simple compounds, which would have been abundant on early Earth, can give rise to a network of simple reactions that produce the three major classes of biomolecules—nucleic acids, amino acids, and lipids—needed for the earliest form of life to get its start. Although the new work does not prove that this is how life started, it may eventually help explain one of the deepest mysteries in modern science.


“This is a very important paper,” says Jack Szostak, a molecular biologist and origin-of-life researcher at Massachusetts General Hospital in Boston, who was not affiliated with the current research. “It proposes for the first time a scenario by which almost all of the essential building blocks for life could be assembled in one geological setting.”


Scientists have long touted their own favorite scenarios for which set of biomolecules formed first. “RNA World” proponents, for example suggest RNA may have been the pioneer; not only is it able to carry genetic information, but it can also serve as a proteinlike chemical catalyst, speeding up certain reactions. Metabolism-first proponents, meanwhile, have argued that simple metal catalysts, as opposed to advanced protein-based enzymes, may have created a soup of organic building blocks that could have given rise to the other biomolecules.


The RNA World hypothesis got a big boost in 2009. Chemists led by John Sutherland at the University of Cambridge in the United Kingdom reported that they had discovered that relatively simple precursor compounds called acetylene and formaldehyde could undergo a sequence of reactions to produce two of RNA’s four nucleotide building blocks, showing a plausible route to how RNA could have formed on its own—without the need for enzymes—in the primordial soup. Critics, though, pointed out that acetylene and formaldehyde are still somewhat complex molecules themselves. That begged the question of where they came from.


For their current study, Sutherland and his colleagues set out to work backward from those chemicals to see if they could find a route to RNA from even simpler starting materials. They succeeded. In the current issue of Nature Chemistry, Sutherland’s team reports that it created nucleic acid precursors starting with just hydrogen cyanide (HCN), hydrogen sulfide (H2S), and ultraviolet (UV) light. What is more, Sutherland says, the conditions that produce nucleic acid precursors also create the starting materials needed to make natural amino acids and lipids. That suggests a single set of reactions could have given rise to most of life’s building blocks simultaneously.


Sutherland’s team argues that early Earth was a favorable setting for those reactions. HCN is abundant in comets, which rained down steadily for nearly the first several hundred million years of Earth’s history. The impacts would also have produced enough energy to synthesize HCN from hydrogen, carbon, and nitrogen. Likewise, Sutherland says, H2S was thought to have been common on early Earth, as was the UV radiation that could drive the reactions and metal-containing minerals that could have catalyzed them.


That said, Sutherland cautions that the reactions that would have made each of the sets of building blocks are different enough from one another—requiring different metal catalysts, for example—that they likely would not have all occurred in the same location. Rather, he says, slight variations in chemistry and energy could have favored the creation of one set of building blocks over another, such as amino acids or lipids, in different places. “Rainwater would then wash these compounds into a common pool,” says Dave Deamer, an origin-of-life researcher at the University of California, Santa Cruz, who wasn’t affiliated with the research.


Could life have kindled in that common pool? That detail is almost certainly forever lost to history. But the idea and the “plausible chemistry” behind it is worth careful thought, Deamer says. Szostak agrees. “This general scenario raises many questions,” he says, “and I am sure that it will be debated for some time to come.”


news.sciencemag.org/biology/2015/03/rese...




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2. There are three sides to every story: your side, my side, and the truth.
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3 years ago  ::  Mar 17, 2015 - 9:27PM #2
Roymond
Posts: 3,779

Hydrogen cyanide and hydrogen sulfide?  Whoa -- all we have to do is cool down Venus, and get it to rain; it's got the stuff in abundance!

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3 years ago  ::  Mar 17, 2015 - 10:30PM #3
Truman47
Posts: 2,423

Mar 17, 2015 -- 9:27PM, Roymond wrote:


Hydrogen cyanide and hydrogen sulfide?  Whoa -- all we have to do is cool down Venus, and get it to rain; it's got the stuff in abundance!




. . . and you'd have to find a way to create a stronger magnetic field. Wink

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3 years ago  ::  Mar 18, 2015 - 1:47PM #4
MMarcoe
Posts: 20,907

So ... no spark that comes from beyond nature is needed to start life.


1. Extremists think that thinking means agreeing with them.
2. There are three sides to every story: your side, my side, and the truth.
3. God is the original nothingness of the universe.
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3 years ago  ::  Mar 18, 2015 - 2:54PM #5
Roymond
Posts: 3,779

Mar 17, 2015 -- 10:30PM, Truman47 wrote:


Mar 17, 2015 -- 9:27PM, Roymond wrote:


Hydrogen cyanide and hydrogen sulfide?  Whoa -- all we have to do is cool down Venus, and get it to rain; it's got the stuff in abundance!




. . . and you'd have to find a way to create a stronger magnetic field. 



I wrote a short story once where humans were tring to colonize other planets, but finding ones with a decent magnetic field wasn't proving easy.  Then a passing alien culture which drifted through space like high-tech interstellar gypsies gave them a device that instantaneously heated planetary cores and got a planetary magnetic feld going.


Then the humans complained the device didn't let them set the planetary rotation period . . . .  the whiners.



Anyway, I've pondered Venus and its magnetic situation.  It apparently doesn't have plate tectonics going, either, and I have an intuition those two may be related.  Maybe if we hit it with a comet big enough to crack the crust, at a sharp angle, could plates start moving?  Or do we even have reason to believe there are plates on Venus?



{inquiring minds want to know}

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3 years ago  ::  Mar 18, 2015 - 2:56PM #6
Roymond
Posts: 3,779

Mar 18, 2015 -- 1:47PM, MMarcoe wrote:


So ... no spark that comes from beyond nature is needed to start life.





Well, we're not quite to being certain of that, but it does seem more and more likely.


I say it's built into the constants of the universe.



BTW, I read an interesting analysis yesterday that given that the speed of light is a constant, then gauge symmetry is required, and thus a fair number of laws and constants are not independent.  I'm not quite sure I follow the argument yet, though.

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3 years ago  ::  Mar 18, 2015 - 3:16PM #7
d_p_m
Posts: 11,236

Mar 18, 2015 -- 2:56PM, Roymond wrote:


BTW, I read an interesting analysis yesterday that given that the speed of light is a constant, then gauge symmetry is required, and thus a fair number of laws and constants are not independent.  I'm not quite sure I follow the argument yet, though.




Yup.


That's why YEC ad hoc arbitrary rewriting of various scientific laws and facts (like the speed of light) while expecting everything else to stay the same (unless they need more ad hoc changes) looks so clueless.

"If you aren't confused by quantum physics, you haven't really understood it."
― Niels Bohr

"As far as the laws of mathematics refer to reality, they are not certain, as far as they are certain, they do not refer to reality."
-- Albert Einstein

"If one is going to engage with the primordial forces of darkness, one must expect a bit of social awkwardness."
-- Penny Dreadful, season one, episode two
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3 years ago  ::  Mar 18, 2015 - 9:59PM #8
Upperlimits
Posts: 3,238

Mar 18, 2015 -- 3:16PM, d_p_m wrote:


Mar 18, 2015 -- 2:56PM, Roymond wrote:


BTW, I read an interesting analysis yesterday that given that the speed of light is a constant, then gauge symmetry is required, and thus a fair number of laws and constants are not independent.  I'm not quite sure I follow the argument yet, though.




Yup.


That's why YEC ad hoc arbitrary rewriting of various scientific laws and facts (like the speed of light) while expecting everything else to stay the same (unless they need more ad hoc changes) looks so clueless.




What do you mean when you use the word "constant?"


Do you mean that given no outside influences, that this is the speed at which light would normally travel? Or that the "constant" speed is the "only" speed at which light is capable of traveling?


The reason I ask is there are some recent experiments that claim to have slowed light down considerably. abcnews.go.com/Technology/story?id=99111 I've also wondered if light can't be sped up in some circumstances. This is speculation on my part, but I wonder if perhaps going over the event horizon of a black hole might do it.


100
According to 2nd Corinthians 3:2, there are five gospels in the world. Matthew, Mark, Luke, John, and the Epistle of ones own life.  Most people will probably never read the first four.

God desires that our lives would bear spiritual fruit - not religious nuts.
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3 years ago  ::  Mar 18, 2015 - 10:22PM #9
rsielin
Posts: 4,997

Mar 18, 2015 -- 9:59PM, Upperlimits wrote:

The reason I ask is there are some recent experiments that claim to have slowed light down considerably. abcnews.go.com/Technology/story?id=99111 I've also wondered if light can't be sped up in some circumstances. This is speculation on my part, but I wonder if perhaps going over the event horizon of a black hole might do it.


Yes, there's a lot known about light refraction caused by light slowing down traveling through matter. And there's more to be learned I suppose.


But that's not the creationist problem. This is the creationists problem: "Nothing can travel faster than the speed of light in a vacuum." "Light in a vacuum always travels at the same speed." The distance between us and deep space is an almost perfect natural vacuum.


There's nothing credible creationists can hang their hat on. Sorry. 


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3 years ago  ::  Mar 18, 2015 - 11:01PM #10
Roymond
Posts: 3,779

Mar 18, 2015 -- 9:59PM, Upperlimits wrote:


Mar 18, 2015 -- 3:16PM, d_p_m wrote:


Mar 18, 2015 -- 2:56PM, Roymond wrote:


BTW, I read an interesting analysis yesterday that given that the speed of light is a constant, then gauge symmetry is required, and thus a fair number of laws and constants are not independent.  I'm not quite sure I follow the argument yet, though.




Yup.


That's why YEC ad hoc arbitrary rewriting of various scientific laws and facts (like the speed of light) while expecting everything else to stay the same (unless they need more ad hoc changes) looks so clueless.




What do you mean when you use the word "constant?"


Do you mean that given no outside influences, that this is the speed at which light would normally travel? Or that the "constant" speed is the "only" speed at which light is capable of traveling?


The reason I ask is there are some recent experiments that claim to have slowed light down considerably. abcnews.go.com/Technology/story?id=99111 I've also wondered if light can't be sped up in some circumstances. This is speculation on my part, but I wonder if perhaps going over the event horizon of a black hole might do it.


100



That doesn't look any different to me than the fact that it takes thousands of years for a photon to get from the center of a star to the outside (if you can even call it the same photon, with all the absorbing and (re-)emitting).


Photons speeing up...  Maybe if they encountered very "thin" space that was about to "rip open" and let a new universe pop in.  Cool

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