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pleco
SFN Addict
USA
2998 Posts |
 Posted - 10/17/2008 : 14:58:17
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Source
In his 1953 paper, Dr. Miller reported that he had detected five amino acids produced by the original apparatus. Mr. Johnson's work, using modern techniques, revealed small amounts of nine additional amino acids in those samples. In the residues from the apparatus with the steam injector, the scientists detected 22 amino acids including 10 that had never been identified before from the Miller-Urey experiment.
It just opens our eyes, Dr. Bada said. It's still revealing new things. What else is there that we haven't found out from this experiment? |
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by Filthy
The neo-con methane machine will soon be running at full fart. |
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filthy
SFN Die Hard
USA
14408 Posts |
 Posted - 10/17/2008 : 15:39:58 [Permalink]
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Marvelous, isn't it? It nicely demonstrates that just because an experiment is finished, it is not necessarily ended. I wonder how many other retired projects this one will dust off and put back on the bench just for a look&see, and what the results of those lookits might turn out be.
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist! 
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bngbuck
SFN Addict
USA
2437 Posts |
Posted - 10/18/2008 : 00:31:34 [Permalink]
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Filthy.....
Unstated in the Times article is the relationship between the amino acids and life. Although it appears that amino acids are certainly related to, and essential elements of, many of the life processes - being the essential building blocks of protien formation, I could find nothing that suggests that the mere presence of (or creation of) amino acids necessarily constitutes a precondition for the appearence of life forms.
Three or four hours into amino acid chemistry, protein formation, peptide bonds, and other esoterica left me with a large headache, tired eyes and a desire to learn more.
What do you, Filthy, or any biological or life sciences professionals reading here know about the implication in the Times article and elsewhere, that the appearance of amino acids in some manner presages the development of life? Given the incredible number and variety of the amino acids, I don't understand why anyone would get excited about how sparks in a chemical soup or the arrival of a meteorite containing amino acids could be some sort of clue to the origin of life?
To achieve homeostasis, organization, metabolism, growth, adaptation, response to stimulation, and reproduction (wiki's criteria for mandatory qualities of life organisms); it seems to me that a hell of a lot more than amino acids have to be present. An organism seems to be necessary, for one thing. Even if the experiments could successfully create protein, dead beef is still protein!
What's the big deal with amino acids?
Anyone know anything about this field? I obviously don't! |
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filthy
SFN Die Hard
USA
14408 Posts |
 Posted - 10/18/2008 : 02:52:07 [Permalink]
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I don't either. But I wait & watch because sooner or later the abiogenesis hypothesis will become supported theory and this is just a tiny step in that direction. Or perhaps it might inspire some researcher to say: "Hey, what if...." and go off in another direction, leading to the actual event.
Or maybe God done it after all, eh? 
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist!
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Hawks
SFN Regular
Canada
1383 Posts |
Posted - 10/18/2008 : 06:42:33 [Permalink]
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Originally posted by bngbuck
What's the big deal with amino acids?
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Probably not a lot, really. The Earth's early atmosphere was probably nothing like that used in the experiments. The most interesting part probably has to do with the fact that it was previously thought that amino acids were only created by living organisms, something that was clearly shown wrong.
[rant]Hey, it's like something that requires an irreducibly complex apparatus to become created demonstres that the apparatus was neither irreducibly complex or even existent..... But of course, to an ID supporter, the experiment itself was irreducibly complex and intelligently guideded so, to them, it wouldn't have shown anything like that.[/rant] |
METHINKS IT IS LIKE A WEASEL
It's a small, off-duty czechoslovakian traffic warden! |
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Simon
SFN Regular
USA
1992 Posts |
Posted - 10/18/2008 : 10:05:07 [Permalink]
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Amino acids are complex molecules.
Proteins are essentially chains of amino-acids and are quite easy to obtain once you get the amino-acids.
The main reason why this experiment was so interesting is that, at that time, almost all known biological functions were performed by proteins. So, amino-acids were a really big deal as they were thought to be the first step on the path to life.
Since then, we discover quite a few ribozymes; RNA molecules that could act as an enzyme. So, nowadays, most people consider that primitive life probably relied on ribosyme and then the amino-acids evolved.
So the experience is not as important at it used to be (not to mention that Miller did not know the atmosphere composition as well as we do know).
Nonetheless; it is still interesting as an evidence than even very complex molecules will be obtained spontaneously and fast provided the right conditions. |
Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there on a mote of dust suspended in a sunbeam.
Carl Sagan - 1996 |
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TFarnon
New Member
USA
17 Posts |
Posted - 11/07/2008 : 20:55:36 [Permalink]
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Originally posted by bngbuck
Filthy.....
Unstated in the Times article is the relationship between the amino acids and life. Although it appears that amino acids are certainly related to, and essential elements of, many of the life processes - being the essential building blocks of protien formation, I could find nothing that suggests that the mere presence of (or creation of) amino acids necessarily constitutes a precondition for the appearence of life forms.
Three or four hours into amino acid chemistry, protein formation, peptide bonds, and other esoterica left me with a large headache, tired eyes and a desire to learn more.
ONLY 3 or 4 hours? And it's not esoterica. It's basic biochemistry. Get thee to a university!
What do you, Filthy, or any biological or life sciences professionals reading here know about the implication in the Times article and elsewhere, that the appearance of amino acids in some manner presages the development of life? Given the incredible number and variety of the amino acids, I don't understand why anyone would get excited about how sparks in a chemical soup or the arrival of a meteorite containing amino acids could be some sort of clue to the origin of life?
Because amino acids (AA's) in chains are polypeptides or proteins (depending on how many AA's are in the chain), and those proteins can catalyze other reactions, including autocatalytic reactions. Peptide bonds are the result of a catalytic reaction mediated by (surprise) other proteins (or nucleic acids--I'll get to that), and because peptide bonds form moderately easily under the right conditions even without the presence of other biomolecules. Peptide bond formation is "just" a dehydration reaction.
Now--there is one other polymer essential to life as we know it, and that's a nucleic acid polymer. We know these as DNA and RNA. DNA, while it contains a template for the synthesis of every biologically produced protein on this planet, isn't as chemically important as its' less stable but infinitely more interesting relative: RNA. Because RNA is single-stranded (Okay, don't be picky--I KNOW there are double-stranded RNA molecules and single-stranded DNA molecules, but they are largely confined to viruses), it can fold into reactive conformations just as proteins do. Peptide bond formation in living systems turns out to be catalyzed not so much by other proteins, but by a catalytic RNA segment. RNA also can have autocatalytic properties such as self-splicing and the dehydration reaction needed to add nucleotides to a growing chain of nucleotides.
What makes both of these molecules so interesting, even in monomeric form, is that they are both composed of carbon, nitrogen and oxygen (and phosphorus in the case of nucleotides). Carbon, nitrogen and oxygens have unique reactive properties because of the number of electrons circling their nuclei. These are three of the elements with an ability to form covalent bonds, the strongest of all molecular bonds. It's the chemical nature of these elements that lead to the potential for positive feedback mechanisms, and those in turn generate the potential for the chemical reactions we call metabolism.
To achieve homeostasis, organization, metabolism, growth, adaptation, response to stimulation, and reproduction (wiki's criteria for mandatory qualities of life organisms); it seems to me that a hell of a lot more than amino acids have to be present. An organism seems to be necessary, for one thing. Even if the experiments could successfully create protein, dead beef is still protein!
But "protein" isn't just "protein" until it's completely and thoroughly denatured (by heat or chemical treatment). Proteins are very interesting molecules--incredibly diverse, with a huge array of properties and catalytic abilities.
What's the big deal with amino acids?
Amino acids are the subunits of the polymers known as proteins.
Anyone know anything about this field? I obviously don't!
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I can tell. Okay. I shouldn't be snotty about it. It's really cool stuff. It sounds very patronizing, but if you spend some time and effort really studying biochemistry, you will understand. Or go stark raving bonkers. Or both. |
Bacteria RULE, Hominids drool |
| Edited by - TFarnon on 11/07/2008 20:59:10 |
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HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 11/08/2008 : 15:18:47 [Permalink]
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Originally posted by TFarnon
I can tell. Okay. I shouldn't be snotty about it. It's really cool stuff. It sounds very patronizing, but if you spend some time and effort really studying biochemistry, you will understand. Or go stark raving bonkers. Or both.
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The "Or both" part of the above seems a fine working hypothesis for the naturalistic creation of mad scientists.
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
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Abiogenesis Part 2: Electric Boogaloo
