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Any expert commentary to fully explain the following papers to me welcome and of course encouraged.........I certainly have heard about the "Miller/Urey experiment, mostly that it was inconclusive? What do the following papers say about that result, in simple language?

https://www.ncbi.nlm.nih.gov/pubmed/26508401 

Chemical Analysis of a "Miller-Type" Complex Prebiotic Broth: Part I: Chemical Diversity, Oxygen and Nitrogen Based Polymers.

Abstract:

In a famous experiment Stanley Miller showed that a large number of organic substances can emerge from sparking a mixture of methane, ammonia and hydrogen in the presence of water (Miller, Science 117:528-529, 1953). Among these substances Miller identified different amino acids, and he concluded that prebiotic events may well have produced many of Life's molecular building blocks. There have been many variants of the original experiment since, including different gas mixtures (Miller, J Am Chem Soc 77:2351-2361, 1955; Oró Nature 197:862-867, 1963; Schlesinger and Miller, J Mol Evol 19:376-382, 1983; Miyakawa et al., Proc Natl Acad Sci 99:14,628-14,631, 2002). Recently some of Miller's remaining original samples were analyzed with modern equipment (Johnson et al. Science 322:404-404, 2008; Parker et al. Proc Natl Acad Sci 108:5526-5531, 2011) and a total of 23 racemic amino acids were identified. To give an overview of the chemical variety of a possible prebiotic broth, here we analyze a "Miller type" experiment using state of the art mass spectrometry and NMR spectroscopy. We identify substances of a wide range of saturation, which can be hydrophilic, hydrophobic or amphiphilic in nature. Often the molecules contain heteroatoms, with amines and amides being prominent classes of molecule. In some samples we detect ethylene glycol based polymers. Their formation in water requires the presence of a catalyst. Contrary to expectations, we cannot identify any preferred reaction product. The capacity to spontaneously produce this extremely high degree of molecular variety in a very simple experiment is a remarkable feature of organic chemistry and possibly prerequisite for Life to emerge. It remains a future task to uncover how dedicated, organized chemical reaction pathways may have arisen from this degree of complexity.

 

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https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5705758/

Origins of Life and Evolution of the Biosphere:

Chemical Analysis of a “Miller-Type” Complex Prebiotic Broth:

Abstract:

We have analyzed the chemical variety obtained by Miller-Urey-type experiments using nuclear magnetic resonance (NMR) spectroscopy and coherent anti-Stokes Raman scattering (CARS) spectroscopy, gas chromatography followed by mass spectrometry (GC/MS) and two-dimensional gas chromatography followed by mass spectrometry (GCxGC/MS). In the course of a running Miller-Urey-type experiment, a hydrophobic organic layer emerged besides the hydrophilic aqueous phase and the gaseous phase that were initially present. The gas phase mainly consisted of aromatic compounds and molecules containing C≡C or C≡N triple bonds. The hydrophilic phase contained at least a few thousands of different molecules, primarily distributed in a range of 50 and 500 Da. The hydrophobic phase is characterized by carbon-rich, oil-like compounds and their amphiphilic derivatives containing oxygen with tensioactive properties. The presence of a wide range of oxidized molecules hints to the availability of oxygen radicals. We suggest that they intervene in the formation of alkylated polyethylene glycol (PEG) in the oil/water interface. CARS spectroscopy revealed distinct vibrational molecular signatures. In particular, characteristic spectral bands for cyanide compounds were observed if the broth was prepared with electric discharges in the gaseous phase. The characteristic spectral bands were absent if discharges were released onto the water surface. NMR spectroscopy on the same set of samples independently confirmed the observation. In addition, NMR spectroscopy revealed overall high chemical variability that suggests strong non-linearities due to interdependent, sequential reaction steps.

 

 

Posted
On 5/29/2019 at 7:26 AM, beecee said:

Any expert commentary to fully explain the following papers to me welcome and of course encouraged.........I certainly have heard about the "Miller/Urey experiment, mostly that it was inconclusive? What do the following papers say about that result, in simple language?

Hmmm, OK my interpretation for what it is worth and based on my limited understanding...   To me it seems to be conveying that more recent research into the "Miller/Urey experiment"  is telling us that far more organic matter was initiated, and that chemically induced life should be more easy then was once thought, and of course Abiogenesis. How'd I go?

Posted
On 5/28/2019 at 5:26 PM, beecee said:

What do the following papers say about that result, in simple language?

     The papers simply state that in the 65 or 66 years since the original "Miller and Urey" experiments, the ability to analyze the "synthesized organic compounds"  has increased. That and further experiments since 1953 utilizing different 'recipes' seem to indicate that not only are more of the perceived 'building blocks of basic life' produced in these experiments, but that it seems that both nature and scientists have quite a variety of methods of producing these compounds. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5705758/ 

    " Introduction

In 1953, Miller and Urey synthesized organic compounds, including amino acids, from water, methane, ammonia, and hydrogen. This was a spectacular experiment that emulated the conditions on the early Earth (Miller 1953). Since then, many experiments related to the origin of life were performed under various conditions (Miyakawa et al. 2002; Oró 1963; Schlesinger and Miller 1983; Fox 1995; Johnson et al. 2008). Besides amino acids, the formation of relevant precursors of biomolecules such as carboxylic acids, urea, and lipids was observed (Dickerson 1979; Dose and Rauchfuss 1975; Lazcano and Bada 2003; McCollom et al. 1999). Here, we describe the chemical analysis of complex prebiotic broth in experiments of the Miller-Urey type. We used nuclear magnetic resonance (NMR) spectroscopy, coherent anti-Stokes Raman scattering (CARS) spectroscopy, gas chromatography/mass spectrometry (GC/MS), and two-dimensional gas chromatography/mass spectrometry (GCxGC/MS). Different analytical methods were necessary to achieve a comprehensive picture of the complex reaction mixture.  " 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5705758/  

14 hours ago, beecee said:

and of course Abiogenesis

     BTW, I saw nothing in the linked articles pertaining to any "Abiogenesis", perhaps I missed reading that pertinent section of the articles.

  Could you possibly 'copy/paste' the sections of the Linked articles pertaining to any "Abiogenesis" ? 

 

  

Posted (edited)
8 hours ago, et pet said:

  Could you possibly 'copy/paste' the sections of the Linked articles pertaining to any "Abiogenesis" ?   

Abiogenesis, by definition is the "the origin of life"from non-living matter. 

In fact Abiogenesis is really the only scientific answer as to the origin of life universally speaking, considering the possibility of Panspermia. The papers may not have mentioned Abiogenesis per se, but obviously it is what it is pertained to.

<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>

https://www.khanacademy.org/science/biology/history-of-life-on-earth/history-life-on-earth/a/hypotheses-about-the-origins-of-life

Hypotheses about the origins of life

The Oparin-Haldane hypothesis, Miller-Urey experiment, and RNA world.

Key points:

The Earth formed roughly 4.54.54, point, 5 billion years ago, and life probably began between 3.53.53, point, 5 and 3.93.93, point, 9 billion years ago.

The Oparin-Haldane hypothesis suggests that life arose gradually from inorganic molecules, with “building blocks” like amino acids forming first and then combining to make complex polymers.

The Miller-Urey experiment provided the first evidence that organic molecules needed for life could be formed from inorganic components.

Some scientists support the RNA world hypothesis, which suggests that the first life was self-replicating RNA. Others favor the metabolism-first hypothesis, placing metabolic networks before DNA or RNA.

Simple organic compounds might have come to early Earth on meteorites.

Introduction:

If there were other life out there in the universe, how similar do you think it would it be to life on Earth? Would it use DNA as its genetic material, like you and me? Would it even be made up of cells?

We can only speculate about these questions, since we haven't yet found any life forms that hail from off of Earth. But we can think in a more informed way about whether life might exist on other planets (and under what conditions) by considering how life may have arisen right here on our own planet.

In this article, we'll examine scientific ideas about the origin of life on Earth. The when of life's origins (3.53.53, point, 5 billion years ago or more) is well-supported by fossils and radiometric dating. But the how is much less understood. In comparison to the central dogma or the theory of evolution, hypotheses about life's origins are much more...hypothetical. No one is sure which hypothesis is correct – or if the correct hypothesis is still out there, waiting to be discovered.

<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

 

In essence then,  The  definition of Abiogenesis is concerned with the formation of most basic and fundamental simplest lifeforms, from a primordial  soup of chemicals. 

Edited by beecee
Posted
1 hour ago, beecee said:

Abiogenesis, by definition is the "the origin of life"from non-living matter. 

In fact Abiogenesis is really the only scientific answer as to the origin of life universally speaking, considering the possibility of Panspermia. The papers may not have mentioned Abiogenesis per se, but obviously it is what it is pertained to.

<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>

https://www.khanacademy.org/science/biology/history-of-life-on-earth/history-life-on-earth/a/hypotheses-about-the-origins-of-life

Hypotheses about the origins of life

The Oparin-Haldane hypothesis, Miller-Urey experiment, and RNA world.

Key points:

The Earth formed roughly 4.5 billion years ago, and life probably began between 3.5 and 3.9 billion years ago.

The Oparin-Haldane hypothesis suggests that life arose gradually from inorganic molecules, with “building blocks” like amino acids forming first and then combining to make complex polymers.

The Miller-Urey experiment provided the first evidence that organic molecules needed for life could be formed from inorganic components.

Some scientists support the RNA world hypothesis, which suggests that the first life was self-replicating RNA. Others favor the metabolism-first hypothesis, placing metabolic networks before DNA or RNA.

Simple organic compounds might have come to early Earth on meteorites.

Introduction:

If there were other life out there in the universe, how similar do you think it would it be to life on Earth? Would it use DNA as its genetic material, like you and me? Would it even be made up of cells?

We can only speculate about these questions, since we haven't yet found any life forms that hail from off of Earth. But we can think in a more informed way about whether life might exist on other planets (and under what conditions) by considering how life may have arisen right here on our own planet.

In this article, we'll examine scientific ideas about the origin of life on Earth. The when of life's origins (3.53.53, point, 5 billion years ago or more) is well-supported by fossils and radiometric dating. But the how is much less understood. In comparison to the central dogma or the theory of evolution, hypotheses about life's origins are much more...hypothetical. No one is sure which hypothesis is correct – or if the correct hypothesis is still out there, waiting to be discovered.

<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

 

In essence then,  The  definition of Abiogenesis is concerned with the formation of most basic and fundamental simplest lifeforms, from a primordial  soup of chemicals. 

 

Posted (edited)

I am of the cell first then physical replication of those cells via trauma as in surf with each cell providing an environment that allowed for enveloping or extruding hydrophobic molecule Those that built better making cell making molecules became more numerous. Those first cells composed of molecules with hydrophobic and hydrophilic cells naturally created pores where rna could reproduce and make more rna with hydrophobic and hydrophilic ends. The RNA that did this most efficiently made more cells that were broken up on rocks by the surf or other trauma. Eventually the cells would burst due to too much RNA being inside and form more cells and the process would start over. The result was life... 

 

Edited by Moontanman

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