DNA Denaturing through Photon Dissipation: A Possible Route to Archean Non-enzymatic Replication

Mapping Intimacies ◽

10.1101/009126 ◽

2014 ◽

Cited By ~ 3

Author(s):

Karo Michaelian ◽

Norberto Santillán Padilla

Keyword(s):

Origin Of Life ◽

Solar Spectrum ◽

Thermodynamic Process ◽

Equilibrium Thermodynamic ◽

Base Pairs ◽

Synthetic Dna ◽

The Origin Of Life ◽

Average Size ◽

Uv C ◽

Rna And Dna

AbstractFormidable difficulties arise when attempting to explain the non-enzymatic replication, proliferation, and the acquisition of homochirality and information content, of RNA and DNA at the beginnings of life. However, new light can be shed on these problems by viewing the origin of life as a non-equilibrium thermodynamic process in which RNA, DNA and other fundamental molecules of life arose as structures to dissipate the prevailing solar spectrum. Here we present experimental results which demonstrate that the absorption and dissipation of UV-C light by DNA at temperatures below their melting temperature leads to complete and reversible denaturing for small synthetic DNA of 25 base pairs (bp), and to partial and reversible denaturing for 48 bp DNA and for large salmon sperm and yeast DNA of average size 100 kbp. This result has direct bearing on the above mentioned problems and thereby opens the door to a possible thermodynamic route to the origin of life.

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Microscopic Dissipative Structuring at the Origin of Life

10.1101/179382 ◽

2017 ◽

Author(s):

Karo Michaelian

Keyword(s):

Radiative Decay ◽

Double Helix ◽

Solar Spectrum ◽

Conical Intersection ◽

Origin And Evolution ◽

Physical Chemical ◽

Evolution Of Life ◽

The Origin Of Life ◽

Uv C ◽

Rna And Dna

AbstractFundamental molecules of life are suggested to be formed, proliferated, and evolved through microscopic dissipative structuring and autocatalytic replication under the UV-C solar spectrum prevalent at Earth’s surface throughout the Archean. Evidence is given in the numerous salient characteristics of these, including their strong absorption in this spectral region, their rapid non-radiative decay through an inherent conical intersection, UV-C activation (phos-phorylation) of nucleotides, and UV-C induced denaturing of double helix RNA and DNA. The examples of the dissipative structuring and dissipative proliferation of the purines and of single strand DNA are given. This provides a physical-chemical foundation for understanding the origin and evolution of life.

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The setting for the origin of life: a geological– geochemical perspective

The Biochemist ◽

10.1042/bio04006018 ◽

2018 ◽

Vol 40 (6) ◽

pp. 18-21

Author(s):

Martin J. Van Kranendonk

Keyword(s):

Amino Acids ◽

Origin Of Life ◽

Lipid Membranes ◽

Organic Molecule ◽

Organic Geochemistry ◽

Building Blocks ◽

Dna Molecules ◽

Inorganic Geochemistry ◽

The Origin Of Life ◽

Rna And Dna

There are many different scientific aspects involved in the challenge of understanding the origin of life (OoL). These include organic geochemistry – how to make RNA and DNA molecules from the simple organic building blocks delivered from space in the form of amino acids and some other compounds. Other aspects involve the study of inorganic geochemistry – how elements are made available to promote organic molecule complexification, under what conditions will lipid membranes form and how to bring together the different components that make a functioning cell.

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The Tempo and mode(S) of Prebiotic Evolution

International Astronomical Union Colloquium ◽

10.1017/s0252921100014937 ◽

1997 ◽

Vol 161 ◽

pp. 419-429 ◽

Cited By ~ 1

Author(s):

Antonio Lazcano

Keyword(s):

Origin Of Life ◽

Organic Compounds ◽

Biological Evolution ◽

Current Evidence ◽

Early Diversification ◽

Time Period ◽

The Galaxy ◽

History Of ◽

Widespread Phenomenon ◽

The Origin Of Life

AbstractDifferent current ideas on the origin of life are critically examined. Comparison of the now fashionable FeS/H2S pyrite-based autotrophic theory of the origin of life with the heterotrophic viewpoint suggest that the later is still the most fertile explanation for the emergence of life. However, the theory of chemical evolution and heterotrophic origins of life requires major updating, which should include the abandonment of the idea that the appearance of life was a slow process involving billions of years. Stability of organic compounds and the genetics of bacteria suggest that the origin and early diversification of life took place in a time period of the order of 10 million years. Current evidence suggest that the abiotic synthesis of organic compounds may be a widespread phenomenon in the Galaxy and may have a deterministic nature. However, the history of the biosphere does not exhibits any obvious trend towards greater complexity or «higher» forms of life. Therefore, the role of contingency in biological evolution should not be understimated in the discussions of the possibilities of life in the Universe.

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Photochemical Evolution of Interstellar/Precometary Organic Material

International Astronomical Union Colloquium ◽

10.1017/s0252921100014585 ◽

1997 ◽

Vol 161 ◽

pp. 23-47 ◽

Cited By ~ 11

Author(s):

Louis J. Allamandola ◽

Max P. Bernstein ◽

Scott A. Sandford

Keyword(s):

Origin Of Life ◽

Building Blocks ◽

Complex Species ◽

Infrared Observations ◽

Interstellar Ice ◽

Polycyclic Aromatic ◽

Ultraviolet Photolysis ◽

The Origin Of Life ◽

Simple Molecules ◽

Complex Organic

AbstractInfrared observations, combined with realistic laboratory simulations, have revolutionized our understanding of interstellar ice and dust, the building blocks of comets. Since comets are thought to be a major source of the volatiles on the primative earth, their organic inventory is of central importance to questions concerning the origin of life. Ices in molecular clouds contain the very simple molecules H2O, CH3OH, CO, CO2, CH4, H2, and probably some NH3and H2CO, as well as more complex species including nitriles, ketones, and esters. The evidence for these, as well as carbonrich materials such as polycyclic aromatic hydrocarbons (PAHs), microdiamonds, and amorphous carbon is briefly reviewed. This is followed by a detailed summary of interstellar/precometary ice photochemical evolution based on laboratory studies of realistic polar ice analogs. Ultraviolet photolysis of these ices produces H2, H2CO, CO2, CO, CH4, HCO, and the moderately complex organic molecules: CH3CH2OH (ethanol), HC(= O)NH2(formamide), CH3C(= O)NH2(acetamide), R-CN (nitriles), and hexamethylenetetramine (HMT, C6H12N4), as well as more complex species including polyoxymethylene and related species (POMs), amides, and ketones. The ready formation of these organic species from simple starting mixtures, the ice chemistry that ensues when these ices are mildly warmed, plus the observation that the more complex refractory photoproducts show lipid-like behavior and readily self organize into droplets upon exposure to liquid water suggest that comets may have played an important role in the origin of life.

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