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TOPIC: Ingredients for life


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Title: The Origin of Life from Primordial Planets
Authors: Carl H. Gibson (Univ. Cal. San Diego), Rudolph E. Schild (Harvard), N. C. Wickramasinghe (Cardiff Univ.)
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The origin of life and the origin of the universe are among the most important problems of science and they might be inextricably linked. Hydro-gravitational-dynamics (HGD) cosmology predicts hydrogen-helium gas planets in clumps as the dark matter of galaxies, with millions of planets per star. This unexpected prediction is supported by quasar microlensing of a galaxy and a flood of new data from space telescopes. Supernovae from stellar over-accretion of planets produce the chemicals (C, N, O, P etc.) and abundant liquid water domains required for first life and the means for wide scattering of life prototypes. The first life likely occurred promptly following the plasma to gas transition 300,000 years after the big bang while the planets were still warm, and interchanges of material between planets constituted essentially a cosmological primordial soup. Images from optical, radio, and infrared space telescopes suggest life on Earth was neither first nor inevitable.

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Study: Adding UV light helps form "Missing G" of RNA building blocks

For scientists attempting to understand how the building blocks of RNA originated on Earth, guanine -- the G in the four-letter code of life -- has proven to be a particular challenge. While the other three bases of RNA -- adenine (A), cytosine (C) and uracil (U) -- could be created by heating a simple precursor compound in the presence of certain naturally occurring catalysts, guanine had not been observed as a product of the same reactions.
By adding ultraviolet light to a model prebiotic reaction, researchers from the Georgia Institute of Technology and the University of Roma, "La Sapienza", have discovered a route by which the missing guanine could have been formed. They also found that the RNA bases may have been easier to form than previously thought -- suggesting that starting life on Earth might not have been so difficult after all.

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Title: Guanine, Adenine, and Hypoxanthine Production in UV-Irradiated Formamide Solutions: Relaxation of the Requirements for Prebiotic Purine Nucleobase Formation.
Authors: Hannah L. Barks, Ragan Buckley, Gregory A. Grieves, Ernesto Di Mauro, Nicholas V. Hud, Prof., Thomas M. Orlando, Prof.

We demonstrate the formation of adenine, hypoxanthine, and guanine from heated (130 °C), UV-irradiated formamide solutions in the absence of an inorganic catalyst. Evidence is also provided that classical HCN pathways for purine nucleobase production are also active in heated and UV-irradiated formamide reactions.

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Contemporary Work On The Origin Of Life

Work on the origin of life is rapidly entering a phase of significant scientific progress.  I want to discuss at least my view of its contemporary status after a brief historical summary.
I begin with this: It is astonishing, but true, that molecular reproduction in the form of collectively autocatalytic sets of either DNA or RNA or peptides have been made. The most complex, created by Reza Ghadiri at Scripps and his former post-doctoral fellow, Gonen Askanazy, now at Ben Gurion University, consists in nine polypeptides, each 32 amino acids long, that mutually catalyse one another's formation from fragments of each of these nine polypeptides.  Critically, these results demonstrate conclusively that molecular reproduction need not be based on template replicating DNA, RNA.

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Meteorites suggest seeds of life within our solar system

Tiny meteorites found in ultra-pure Antarctic snow may provide scientists with evidence that the building blocks of life may have come from within our own solar system, rather than from the far reaches of space, researchers reported in a paper published online Thursday in the journal Science.
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Scientists find water-ice and organic material on asteroid

Scientists have for the first time detected water-ice and organic compounds on an asteroid, a discovery which may offer insights into how life started on Earth.
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Amino Acid Chirality
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Title: The Origin of Life and the Crystallisation of Aspartic Acid in Water
Authors: Tu Lee  and Yu Kun Lin

The lack of symmetry is ubiquitous in the biological world. It is striking to see that life on earth exclusively utilizes amino acids of the left-handed  configuration to build homochiral proteins despite an equal chance of producing the same amount of left-handed and right-handed (d) enantiomers of amino acids from methane, ammonia, water, and hydrogen at temperatures ranging from 0° to 70 °C under a reducing atmosphere and primitive earth conditions. This puzzling transition from racemic geochemistry to homochiral biochemistry in terrestrial evolution is usually expounded by the possibility of achieving enantioseparation through the methods of chiral fields, parity nonconservation, chiral symmetry breaking, asymmetric adsorption, chiroselective synthesis, cocrystal engineering, enantiomeric enrichment, ultraviolet photolysis, asymmetric autocatalysis, diastereomeric resolution, and racemization. All of those methods are based on the same assumption that either a racemic compound (dl) is crystallised or a conglomerate (d and l) is resolved from a racemic solution filled with randomly oriented free d- and l-enantiomers. However, the assumption of ignoring the liquid structure of the solution phase and its evolution over time may be incorrect for aspartic acid.

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RE: Ingredients for life
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Title: The Origin of Life from Primordial Planets
Authors: Carl H. Gibson (Univ. Cal. San Diego), Rudolph E. Schild (Harvard), N. C. Wickramasinghe (Cardiff Univ.)

The origin of life and the origin of the universe represent two of the most important problems of science. Both are resolved by hydro-gravitational dynamics (HGD) cosmology (Gibson 1996, Schild 1996, Gibson 2009ab), which predicts frozen primordial hydrogen-helium gas planets in clumps as the dark matter of galaxies. Merging Earth-mass planets formed stars, moons and comets to incubate and cosmically seed the first life. Cometary panspermia (Hoyle and Wickramasinghe 1981, 1982; Wickramasinghe et al. 2009) occurs naturally by HGD mechanisms. Comets and moons are fragments from mergers of stardust covered frozen gas planets in their step-wise growth to star mass. Supernovae from stellar over-accretion of planets produce stardust (C, N, O, P etc.) chemical fertilizer. Planets collect this infected radioactive dust gravitationally, to provide liquid water domains in contact with life nutrients seeded with life prototypes. The first mutating, evolving, life from HGD likely occurred promptly, following the plasma to gas transition 300,000 years after the big bang when high densities of galaxies and a superabundance of hot primordial soup kitchens first overcame enormous odds against spontaneous creation (Wickramasinghe 2010, Joseph 2000). Images from optical, radio, and infrared space telescopes suggest life on Earth was neither first nor inevitable.

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Comet crash creates potential for life

Striking a glancing blow to a planet could create the perfect conditions in a comet's icy core to create amino acids - molecules that are vital to forming life on Earth.
This shock-compression theory for making amino acids has been developed by Nir Goldman and his colleagues at the Lawrence Livermore National Laboratory in Livermore, California. Goldman presented their results on 24 March at the American Chemical Society meeting in San Francisco, California.

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Did 'midwife molecule' assemble first life on Earth?

The primordial soup that gave birth to life on Earth may have had an extra, previously unrecognised ingredient: a "molecular midwife" that played a crucial role in allowing the first large biomolecules to assemble from their building blocks.
The earliest life forms are thought by many to have been based not on DNA but on the closely related molecule RNA, because long strands of RNA can act as rudimentary enzymes. This would have allowed a primitive metabolism to develop before life forms made proteins for this purpose.

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