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Old Materials Resurface For "Prebiotic Soup"
AliasMarlowe writes "Stanley Miller performed the famous experiments in the 1950s showing that amino acids and other building blocks for biomolecules could be produced by passing lightning through a mix of simple hydrocarbons, water vapor, and ammonia (thought at the time to approximate the Earth's early atmosphere). Other experiments approximated the environment around volcanic eruptions, but those results were not published. Following his death last year, a former student discovered the materials from those experiments, in labelled vials. Analysis of this material indicates that the conditions around volcanic eruptions (still thought to be representative of such events in the early Earth) resulted in a higher yield of amino acids than the simple lightning experiments, and resulted in a greater variety of amino acids." Pharyngula has a discussion of the Science paper, including a graph of the amino acids produced.
Just add volcano.
Great, just add more fuel to the Scientology fire.
IAANAMB but if you think about it, changes in composition would not void the findings in the experiment. If after the initial experiment the samples were kept in closed vials and out of sunlight, then 60 years later were analyzed for content and the amino acids were found that means one of the following: Either the amino acids were formed in the volcano-like conditions of the original experiment, something more complex was formed in the original experiment and broke down to more simple amino acids over time, or nothing much was formed in the original experiment, but in the ensuing 60 years something reacted to form the amino acids. All of these presuppose the formation of amino acids in either prebiotic earth conditions or sealed-vial-kept-in-a-dark-closet conditions. It would be more surprising if they formed under the latter, than under the former conditions.
As a 60-a-day Marlboro man I regret the half hour lost to smoking every time I go for a swim, so you can image the excitement with which I opened your post. Only to be confronted with something about soup. God, I need a smoke.
Will Safeway Grade A Jumbo eggs work, or do I need a special kind?
I've never understood why many people can't accept the co-existence of science and religion. They do not have to be mutually exclusive, it's just the extremists on both sides which create the problem.
...
Take Christianity and The Big Bang theroy. They work out just fine, so long as the Christian can accept that the Bible may not be a 100% accurate portrayal of how God did it. And the science side doesn't get up in arms with the idea that god wrote the laws of the universe. You know, maybe he dumbed it down a bit so that his bronze age audience could understand it.
My usual view of it is about:
God: In the beginning there was nothing, not time, not space, truly absolutely nothing.
Well, the quiet was nice, but it got boring fast. So, I figured I would write up the basic laws to run a universe, kick start it and see what that got me.
Abraham: Nothing, Universal Laws, kick start, got it. But what do you mean by "no time", how can you have no time?
God: Just go with me on that one, you'll figure it out later.
Abraham:OK.
God:So, the Universe exploded into existence, as it expanded a high energy plasma began to condense down into quarks, anti-quarks and a whole host of other sub-atomic particles. And it was truly chaos. Particles and their anti-particles were colliding and mutually an... Yes, what it is Abraham, why are you raising your hand, do you need to pee?
Abraham: Um, I think you lost me at about "Plasma", and I know what a "cork" is, but what's and "anti-cork", it is some kind of spout?
God: Oh right, a few thousands years early on those, aren't I? Um, how are you with Calculus?
Abraham: Calcu-what?
God: Non-euclidean algebra?
Abraham:
God: Right, fuck it. New clay tablet. In the beginning I said, "Let there be light!" and there was, and it was good. Still with me?
You know, maybe the Bible/Koran/Torah aren't really literal versions of what happened. Maybe they are just metaphors which worked for early man, and God hasn't bothered to update them.
And no matter how fun it is to pick on religious folk, there is really no harm in them believing that there is an invisible sky wizard behind everything. As long as they aren't forcing that belief on others. Or trying to harm others who disagree with them.
Necessity is the mother of invention.
Laziness is the father.
The distribution of amino acids is quite interesting. Eight of the amino acids (glycine, alanine, valine, serine, phenylalanine, aspartic acid, and glutamic acid) are from the 20 "standard" amino acids directly coded for in DNA. Seven more are isomers, close homologs, or simple derivatives of the standard seven (isovaline, 2-methylserine, etc.). Ornithine is not found in proteins, but is found as an intermediate both the natural synthesis and breakdown of other amino acids. It is curiously enough the only amino acid found in the vial which is a base- I would have expected more, given all the ammonia in the experiment atmosphere. I would have expected glutamine and asparagine as well, but they're pretty fragile, and if present, may have been lost in the workup.
Five are aminobutyric or aminoisobutyric acids, which are also not coded for by DNA, but are involved in biochemical processes (the best known example is gamma-aminobutryric acid, GABA, a neurotransmitter). No sulfur in the vial, so the absence of cysteine and methionine is unsurprising. Proline is absent, but in organisms, it is formed from an enzyme-catalyzed ring formation from glutamic acid, so it may not form easily in test tubes.
Phenylalanine was the only aromatic amino acid found, which is unsurprising, given the complexity- in organisms, they tend to be synthesized by multistep enzyme-catalyzed routes, and most organisms high on the food chain have lost this ability. Notably, phenylalanine seems to be present in the vial at about one-millionth the concentration of glycine, so its production is a pretty rare event. And all of the amino acids produced were racemic mixtures, whereas nearly all amino acids utilized in nature are the L-enantiomer. It is still a mystery as to when homochirality first arose.
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."