Proto-metabolism

Last updated

A proto-metabolism is a series of linked chemical reactions in a prebiotic environment that preceded and eventually turned into modern metabolism. Combining ongoing research in astrobiology and prebiotic chemistry, work in this area focuses on reconstructing the connections between potential metabolic processes that may have occurred in early Earth conditions. [1] Proto-metabolism is believed to be simpler than modern metabolism and the Last Universal Common Ancestor (LUCA), as simple organic molecules likely gave rise to more complex metabolic networks. Prebiotic chemists have demonstrated abiotic generation of many simple organic molecules including amino acids, [2] fatty acids, [3] simple sugars, [4] and nucleobases. [5] There are multiple scenarios bridging prebiotic chemistry to early metabolic networks that occurred before the origins of life, also known as abiogenesis. In addition, there are hypotheses made on the evolution of biochemical pathways including the metabolism-first hypothesis, which theorizes how reaction networks dissipate free energy from which genetic molecules and proto-cell membranes later emerge. [6] [7] To determine the composition of key early metabolic networks, scientists have also used top-down approaches to study LUCA and modern metabolism. [8] [9]

Contents

Autocatalytic prebiotic chemistries

Autocatalytic reactions are reactions where the reaction product acts as a catalyst for its own formation. Many researchers that study proto-metabolism agree that early metabolic networks likely originated as a set of chemical reactions that form self-sustaining networks. [10] [11] [12] This set of reactions is commonly referred to as an autocatalytic set. Some prebiotic chemistries focus on these autocatalytic reactions including the formose reaction, HCN oligomerization, and formamide chemistry.

Formose reaction

Discovered in 1861 by Aleksandr Butlerov, the formose reaction is a set of two reactions converting formaldehyde (CH2O) to a mixture of simple sugars. [13] [14] Formaldehyde is an intermediate in the oxidation of simple carbon molecules (e.g. methane) and was likely present in early Earth's atmosphere. [15] The first reaction is the slow conversion of formaldehyde (C1 carbon) to glycolaldehyde (C2 carbon) and occurs through an unknown mechanism. The second reaction is the faster and autocatalytic formation of higher weight aldoses and ketoses. [16] The kinetics of the formose reaction are often described as autocatalytic, as the alkaline reaction uses lowest molecular weight sugars as feedstocks or input molecules into the reaction. [11] Self-organized autocatalytic networks, like the formose reaction, would allow for adaptation to changing prebiotic environmental conditions. [11] As a proof-of-concept, Robinson and colleagues demonstrated how changing environmental conditions and catalyst availability can impact the resultant sugar products. [12]

In the past, many researchers have suggested the importance of this reaction for abiogenesis and the origins of metabolism because it can lead to ribose. Ribose is a building block of RNA and an important precursor in proto-metabolism. However, there are limitations for the formose reaction to be the chemical origin of sugars including the low chemoselectivity for ribose and high complexity of the final reaction mixture. [17] In addition, a direct joining together of ribose, a nucleobase, and phosphate to make a ribonucleotide (the building block of RNA) is not currently chemically feasible. [18] Alternative prebiotic mechanisms have been proposed including cyanosulfidic prebiotic chemistries.

HCN oligomerization

On Earth, hydrogen cyanide (HCN) is made in volcanos, lightning, and reducing atmospheres like the Miller-Urey experiment. [19] On the Hadean Earth, large impactor events and active hydrothermal processes likely contributed to widespread metal production and metal-based proto-metabolism. [20] Hydrogen cyanide has also been detected in meteorites and atmospheres in the outer solar system. [21] [22]

HCN-derived polymers are the oligomer or hydrolysis products of HCN. [23] These polymers can be synthesized from HCN or cyanide salts often in alkaline conditions, but they have been observed in a wide range of experimental conditions. [5] [24] HCN readily reacts with itself [25] to produce many HCN polymers and biologically-relevant compounds like nucleobases, [5] [26] amino acids, [27] and carboxylic acids. [28] The diversity of products could point to a plausible proto-metabolic network of HCN oligomerization reactions. Although, some groups point to low HCN concentrations in early Earth and low chemioselectivity of key biologically-relevant products, similar to the formose reaction. [29] Others have shown that abundant HCN is produced after large impacts [30] and that high specificity and yield can be achieved. [31]

Formamide chemistry

Formamide (NH2CHO) is the simplest naturally-occurring amide. Similar to HCN, formamide can form naturally. [32] Formamide has specific physical and stability properties possibly suitable for a universal prebiotic precursor for early proto-metabolic networks. [11] For example, it has four universal atomic elements ubiquitous to life: C, H, O, N. The presence of unique functional groups involving oxygen and nitrogen support reaction chemistries to build key biomolecules like amino acids, sugars, nucleosides and other key intermediates of other prebiotic reactions (e.g. the citric acid cycle). [11] [33] In addition, early Earth geological features like hydrothermal pores might support formamide chemistry and synthesis of key prebiotic biomolecules with concentration requirements. [34]

Overall, formamide chemistry can support connections and substrates needed to support prebiotic biomolecule synthesis including the formose reaction, Strecker synthesis, HCN oligomerization, or the Fischer-Tropsch process. [11] [35] In addition, formamide can be easily concentrated through evaporation reactions as it has a boiling point of 210C. [32] [36] Although this reaction has high versatility across one-carbon atom precursors, the connections between different biosynthetic pathways are yet to be directly explored experimentally.

Experimental reconstruction

Many research groups are actively attempting experimental reconstruction of the interactions between prebiotic reactions. One major consideration is the ability for these reactions to operate in the same environmental conditions. [31] These one-pot syntheses would likely push the reaction towards specific subgroups of molecules. [29] The key to building proto-metabolic scenarios involves coupling constructive and interconversion reactions. [11] Constructive reactions use autocatalytic prebiotic chemistries to increase the structural complexity of the original molecule, while interconversion reactions connect different prebiotic chemistries by changing the functional groups appended to the original molecule. A functional group is a group of atoms that has similar properties whenever it appears in different molecules. These interconversion reactions and functional group transformations can lead to new prebiotic chemistries and precursor molecules.

Cyanosulfidic scenario

Cyanosulfidic scenarios are mechanisms for proto-metabolism proposed by the Eschenmoser and Sutherland groups. [37] [31] Research from the Eschenmoser group suggested that interactions between HCN and aldehydes can catalyze the formation of diaminomaleodinitrile (DAMN). Iterations of this cycle would generate multiple intermediate metabolites and key biomolecular precursors through functional group transformations by hydrolytic and redox processes. To expand upon this finding, the Sutherland group experimentally assessed the assembly of biomolecular building blocks from prebiotic intermediates and one-carbon feedstocks. [31] They synthesized precursors of ribonucleotides, amino acids and lipids from the reactants of hydrogen cyanide, acetylene, acrylonitrile (product of cyanide and acetylene), and dihydroxyacetone (stable triose isomer of glyceraldehyde and phosphate). These reactions are driven by UV light and use hydrogen sulfide (H2S) as the primary reductant in these reactions. As each of these synthesis reactions was tested independently and some reactions require periodic input of additional reactants, these biomolecular precursors were not strictly generated through a one-pot synthesis expected of early Earth environments. In the same work, these authors argue that flow chemistry or the movement of reactants through water could generate the conditions favorable for the synthesis of these molecules.

Glyoxylate scenario

Eschenmoser also proposed a parallel scenario where the connections between prebiotic reactions would be connected by glyoxylate, a simple α-ketoacid, produced by HCN oligomerization and hydrolysis. [38] In this work, Eschenmoser proposes potential schemes to generate both informational oligomers and other key autocatalytic reactions from plausible one-carbon sources (HCN, CO, CO2).

The Krishnamurthy group at Scripps experimentally expanded on this theory. [39] In mild aqueous conditions, they demonstrated that the reaction of glyoxylate and pyruvate can produce a series of α-ketoacid intermediates constituting the reductive tricarboxylic acid (TCA) cycle. This reaction proceeded without metal or enzyme catalysts as glyoxylate acted as both the carbon source and reducing agent in the reaction. Similarly, the Moran group have also reported pyruvate and glyoxylate can react in warm iron-rich water to produce TCA intermediates and some amino acids. [40] [41] Their work has successfully reconstructed 9 out of 11 TCA intermediates and 5 universal metabolic precursors. [11] [40] [41] [42] [43] Additional experimental analysis is needed to connect this scenario to modern metabolism.[ citation needed ]

Energy sources

Unlike proto-metabolism, the bioenergetic pathways powering modern metabolism are well understood. In early Earth conditions, there were mainly three kinds of energy to support early metabolic pathways: high energy sources to catalyze monomers, lower energy sources to support condensation or polymerization, and energy carriers that support transfer of energy from the environment to metabolic networks. [25] Examples of high energy sources include photochemical energy from ultraviolet light, atmospheric electric discharge, and geological electrochemical energy. These energy sources would support synthesis of biological monomers or feedstocks for proto-metabolism. In contrast, examples of lower energy sources for assembly of more complex molecules include anhydrous heat, mineral-catalyzed synthesis, and sugar-driven reactions. Energy carrier molecules could allow for propagation of the energy through the metabolic networks likely resembled modern energy carriers including ATP and NADH. Both energy carriers are nucleotide-based molecules and likely originated early in metabolism. [44]

Metabolism-first hypothesis

Metabolism-first hypothesis suggests that autocatalytic networks of metabolic reactions were the first forms of life. [45] This is an alternative hypothesis to RNA-world, which is a genes-first hypothesis. It was first proposed by Martynas Ycas in 1955. [46] Many recent work in this area is focused in computational modeling of theoretical prebiotic networks. [47] [48] [49] [50]

Metabolism-first proponents postulate that replication and genetic machinery could not arise without the accumulation of the molecules needed for replication. [51] [6] Alone, simple connections between prebiotic synthesis reactions could form key organic molecules and once encapsulated by a membrane would constitute the first cells. These reactions could be catalyzed by various inorganic molecules or ions and stabilized by solid surfaces. [52] Molecular self-replicators and enzymes would emerge later, with these future metabolisms better resembling modern metabolism.

One critique for the metabolism-first hypothesis for abiogenesis is they would also need self-replicating abilities with a high degree of fidelity. [53] If not, the chemical networks with greater fitness in early Earth would not be preserved. There is limited experimental evidence for these theories, so additional exploration in this area is needed to determine the feasibility of a metabolism-first origins of life.

Related Research Articles

<span class="mw-page-title-main">Metabolism</span> Set of chemical reactions in organisms

Metabolism is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the conversion of food to building blocks of proteins, lipids, nucleic acids, and some carbohydrates; and the elimination of metabolic wastes. These enzyme-catalyzed reactions allow organisms to grow and reproduce, maintain their structures, and respond to their environments. The word metabolism can also refer to the sum of all chemical reactions that occur in living organisms, including digestion and the transportation of substances into and between different cells, in which case the above described set of reactions within the cells is called intermediary metabolism.

<span class="mw-page-title-main">Miller–Urey experiment</span> Experiment testing the origin of life

The Miller–Urey experiment (or Miller experiment) was an experiment in chemical synthesis carried out in 1952 that simulated the conditions thought at the time to be present in the atmosphere of the early, prebiotic Earth. It is seen as one of the first successful experiments demonstrating the synthesis of organic compounds from inorganic constituents in an origin of life scenario. The experiment used methane (CH4), ammonia (NH3), hydrogen (H2), in ratio 2:2:1, and water (H2O). Applying an electric arc (the latter simulating lightning) resulted in the production of amino acids.

<span class="mw-page-title-main">Nucleotide</span> Biological molecules constituting nucleic acids

Nucleotides are organic molecules composed of a nitrogenous base, a pentose sugar and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules within all life-forms on Earth. Nucleotides are obtained in the diet and are also synthesized from common nutrients by the liver.

<span class="mw-page-title-main">Purine</span> Heterocyclic aromatic organic compound

Purine is a heterocyclic aromatic organic compound that consists of two rings fused together. It is water-soluble. Purine also gives its name to the wider class of molecules, purines, which include substituted purines and their tautomers. They are the most widely occurring nitrogen-containing heterocycles in nature.

<span class="mw-page-title-main">RNA world</span> Hypothetical stage in the early evolutionary history of life on Earth

The RNA world is a hypothetical stage in the evolutionary history of life on Earth in which self-replicating RNA molecules proliferated before the evolution of DNA and proteins. The term also refers to the hypothesis that posits the existence of this stage.

<span class="mw-page-title-main">Adenine</span> Chemical compound in DNA and RNA

Adenine is a purine nucleotide base. It is one of the four nucleobases in the nucleic acids of DNA, the other three being guanine (G), cytosine (C), and thymine (T). Adenine derivatives have various roles in biochemistry including cellular respiration, in the form of both the energy-rich adenosine triphosphate (ATP) and the cofactors nicotinamide adenine dinucleotide (NAD), flavin adenine dinucleotide (FAD) and Coenzyme A. It also has functions in protein synthesis and as a chemical component of DNA and RNA. The shape of adenine is complementary to either thymine in DNA or uracil in RNA.

The iron–sulfur world hypothesis is a set of proposals for the origin of life and the early evolution of life advanced in a series of articles between 1988 and 1992 by Günter Wächtershäuser, a Munich patent lawyer with a degree in chemistry, who had been encouraged and supported by philosopher Karl R. Popper to publish his ideas. The hypothesis proposes that early life may have formed on the surface of iron sulfide minerals, hence the name. It was developed by retrodiction from extant biochemistry in conjunction with chemical experiments.

<span class="mw-page-title-main">Leslie Orgel</span> British chemist

Leslie Eleazer Orgel FRS was a British chemist. He is known for his theories on the origin of life.

<span class="mw-page-title-main">Formamide</span> Chemical compound

Formamide is an amide derived from formic acid. It is a colorless liquid which is miscible with water and has an ammonia-like odor. It is chemical feedstock for the manufacture of sulfa drugs and other pharmaceuticals, herbicides and pesticides, and in the manufacture of hydrocyanic acid. It has been used as a softener for paper and fiber. It is a solvent for many ionic compounds. It has also been used as a solvent for resins and plasticizers. Some astrobiologists suggest that it may be an alternative to water as the main solvent in other forms of life.

<span class="mw-page-title-main">Glycolaldehyde</span> Organic compound (HOCH2−CHO)

Glycolaldehyde is the organic compound with the formula HOCH2−CHO. It is the smallest possible molecule that contains both an aldehyde group and a hydroxyl group. It is a highly reactive molecule that occurs both in the biosphere and in the interstellar medium. It is normally supplied as a white solid. Although it conforms to the general formula for carbohydrates, Cn(H2O)n, it is not generally considered to be a saccharide.

The formose reaction, discovered by Aleksandr Butlerov in 1861, and hence also known as the Butlerov reaction, involves the formation of sugars from formaldehyde. The term formose is a portmanteau of formaldehyde and aldose.

<span class="mw-page-title-main">Albert Eschenmoser</span> Swiss organic chemist (1925–2023)

Albert Jakob Eschenmoser (5 August 1925 – 14 July 2023) was a Swiss organic chemist, best known for his work on the synthesis of complex heterocyclic natural compounds, most notably vitamin B12. In addition to his significant contributions to the field of organic synthesis, Eschenmoser pioneered work in the Origins of Life (OoL) field with work on the synthetic pathways of artificial nucleic acids. Before retiring in 2009, Eschenmoser held tenured teaching positions at the ETH Zurich and The Skaggs Institute for Chemical Biology at The Scripps Research Institute in La Jolla, California as well as visiting professorships at the University of Chicago, Cambridge University, and Harvard.

A protocell is a self-organized, endogenously ordered, spherical collection of lipids proposed as a rudimentary precursor to cells during the origin of life. A central question in evolution is how simple protocells first arose and how their progeny could diversify, thus enabling the accumulation of novel biological emergences over time. Although a functional protocell has not yet been achieved in a laboratory setting, the goal to understand the process appears well within reach.

<span class="mw-page-title-main">Abiogenesis</span> Life arising from non-living matter

Abiogenesis is the natural process by which life arises from non-living matter, such as simple organic compounds. The prevailing scientific hypothesis is that the transition from non-living to living entities on Earth was not a single event, but a process of increasing complexity involving the formation of a habitable planet, the prebiotic synthesis of organic molecules, molecular self-replication, self-assembly, autocatalysis, and the emergence of cell membranes. The transition from non-life to life has never been observed experimentally, but many proposals have been made for different stages of the process.

<span class="mw-page-title-main">Diaminomaleonitrile</span> Chemical compound

Diaminomaleonitrile (DAMN) is an organic compound composed of two amino groups and two nitrile groups bonded to a central alkene unit. The systematic name reflects its relationship to maleic acid. DAMN form by oligomerization of hydrogen cyanide. It is the starting point for the synthesis of several classes of heterocyclic compounds. It has been considered as a possible organic chemical present in prebiotic conditions.

Formamide-based prebiotic chemistry is a reconstruction of the beginnings of life on Earth, assuming that formamide could accumulate in sufficiently high amounts to serve as the building block and reaction medium for the synthesis of the first biogenic molecules.

A scenario is a set of related concepts pertinent to the origin of life (abiogenesis), such as the iron-sulfur world. Many alternative abiogenesis scenarios have been proposed by scientists in a variety of fields from the 1950s onwards in an attempt to explain how the complex mechanisms of life could have come into existence. These include hypothesized ancient environments that might have been favourable for the origin of life, and possible biochemical mechanisms.

<span class="mw-page-title-main">Prebiotic atmosphere</span>

The prebiotic atmosphere is the second atmosphere present on Earth before today's biotic, oxygen-rich third atmosphere, and after the first atmosphere of Earth's formation. The formation of the Earth, roughly 4.5 billion years ago, involved multiple collisions and coalescence of planetary embryos. This was followed by a <100 million year period on Earth where a magma ocean was present, the atmosphere was mainly steam, and surface temperatures reached up to 8,000 K (14,000 °F). Earth's surface then cooled and the atmosphere stabilized, establishing the prebiotic atmosphere. The environmental conditions during this time period were quite different from today: the Sun was ~30% dimmer overall yet brighter at ultraviolet and x-ray wavelengths, there was a liquid ocean, it is unknown if there were continents but oceanic islands were likely, Earth's interior chemistry was different, and there was a larger flux of impactors hitting Earth's surface.

A warm little pond is a hypothetical terrestrial shallow water environment on early Earth under which the origin of life could have occurred. The term was originally coined by Charles Darwin in an 1871 letter to his friend Joseph Dalton Hooker. This idea is related to later work such as the Oparin-Haldane hypothesis and the Miller–Urey experiment, which respectively provided a hypothesis for life’s origin from a primordial soup of organics and a proof of concept for the mechanism by which biomolecules and their precursors may have formed.

Cyanosulfidic prebiotic synthesis is a proposed mechanism for the origin of the key chemical building blocks of life. It involves a systems chemistry approach to synthesize the precursors of amino acids, ribonucleotides, and lipids using the same starting reagents and largely the same plausible early Earth conditions. Cyanosulfidic prebotic synthesis was developed by John Sutherland and co-workers at the Laboratory of Molecular Biology in Cambridge, England.

References

  1. ↑ "'Impossible' chemistry may reveal origins of life on Earth". Science. 2022-04-04. Retrieved 2024-01-02.
  2. ↑ Islam, Saidul; Powner, Matthew W. (April 2017). "Prebiotic Systems Chemistry: Complexity Overcoming Clutter". Chem. 2 (4): 470–501. doi: 10.1016/j.chempr.2017.03.001 . ISSN   2451-9294.
  3. ↑ McCollom, Thomas M.; Ritter, Gilles; Simoneit, Bernd R. T. (1999). "Lipid Synthesis Under Hydrothermal Conditions by Fischer- Tropsch-Type Reactions". Origins of Life and Evolution of the Biosphere. 29 (2): 153–166. Bibcode:1999OLEB...29..153M. doi:10.1023/a:1006592502746. ISSN   0169-6149. PMID   10227201. S2CID   25687489.
  4. ↑ Benner, Steven A.; Kim, Hyo-Joong; Carrigan, Matthew A. (2012-03-28). "Asphalt, Water, and the Prebiotic Synthesis of Ribose, Ribonucleosides, and RNA". Accounts of Chemical Research. 45 (12): 2025–2034. doi:10.1021/ar200332w. ISSN   0001-4842. PMID   22455515.
  5. 1 2 3 Oro, J.; Kimball, A. P. (August 1961). "Synthesis of purines under possible primitive earth conditions. I. Adenine from hydrogen cyanide". Archives of Biochemistry and Biophysics. 94 (2): 217–227. doi:10.1016/0003-9861(61)90033-9. ISSN   0003-9861. PMID   13731263.
  6. 1 2 Scossa, Federico; Fernie, Alisdair R. (2020). "The evolution of metabolism: How to test evolutionary hypotheses at the genomic level". Computational and Structural Biotechnology Journal. 18: 482–500. doi:10.1016/j.csbj.2020.02.009. ISSN   2001-0370. PMC   7063335 . PMID   32180906.
  7. ↑ "Metabolism First as Evidence of Evolution". www.labxchange.org. Retrieved 2024-01-02.
  8. ↑ Cowing, Keith (2023-08-15). "Scientists Outline A New Strategy For Understanding The Origin Of Life". Astrobiology. Retrieved 2024-01-02.
  9. ↑ "Rutgers Researchers Identify the Origins of Metabolism". www.rutgers.edu. Retrieved 2024-01-02.
  10. ↑ Hordijk, Wim; Steel, Mike (2018-12-08). "Autocatalytic Networks at the Basis of Life's Origin and Organization". Life. 8 (4): 62. Bibcode:2018Life....8...62H. doi: 10.3390/life8040062 . ISSN   2075-1729. PMC   6315399 . PMID   30544834.
  11. 1 2 3 4 5 6 7 8 Nogal, Noemí; Sanz-Sánchez, Marcos; Vela-Gallego, Sonia; Ruiz-Mirazo, Kepa; de la Escosura, Andrés (2023). "The protometabolic nature of prebiotic chemistry". Chemical Society Reviews. 52 (21): 7359–7388. doi:10.1039/D3CS00594A. ISSN   0306-0012. PMC   10614573 . PMID   37855729.
  12. 1 2 Robinson, William E.; Daines, Elena; van Duppen, Peer; de Jong, Thijs; Huck, Wilhelm T. S. (June 2022). "Environmental conditions drive self-organization of reaction pathways in a prebiotic reaction network". Nature Chemistry. 14 (6): 623–631. Bibcode:2022NatCh..14..623R. doi:10.1038/s41557-022-00956-7. hdl: 2066/250891 . ISSN   1755-4330. PMID   35668214. S2CID   238709887.
  13. ↑ Cleaves II, H. James (2008-07-30). "The prebiotic geochemistry of formaldehyde". Precambrian Research. 164 (3–4): 111–118. Bibcode:2008PreR..164..111C. doi:10.1016/j.precamres.2008.04.002.
  14. ↑ Butlerow, A. (January 1861). "Bildung einer zuckerartigen Substanz durch Synthese". Justus Liebigs Annalen der Chemie. 120 (3): 295–298. doi:10.1002/jlac.18611200308. ISSN   0075-4617.
  15. ↑ Masuda, Saeka; Furukawa, Yoshihiro; Kobayashi, Takamichi; Sekine, Toshimori; Kakegawa, Takeshi (April 2021). "Experimental Investigation of the Formation of Formaldehyde by Hadean and Noachian Impacts". Astrobiology. 21 (4): 413–420. Bibcode:2021AsBio..21..413M. doi:10.1089/ast.2020.2320. ISSN   1531-1074. PMID   33784199. S2CID   232429925.
  16. ↑ Delidovich, Irina V.; Simonov, Alexandr N.; Taran, Oxana P.; Parmon, Valentin N. (July 2014). "Catalytic Formation of Monosaccharides: From the Formose Reaction towards Selective Synthesis". ChemSusChem. 7 (7): 1833–1846. Bibcode:2014ChSCh...7.1833D. doi:10.1002/cssc.201400040. ISSN   1864-5631. PMID   24930572.
  17. ↑ Zhao, Ze-Run; Wang, Xiao (December 2021). "A plausible prebiotic selection of ribose for RNA - formation, dynamic isolation, and nucleotide synthesis based on metal-doped-clays". Chem. 7 (12): 3292–3308. doi: 10.1016/j.chempr.2021.09.002 . ISSN   2451-9294. S2CID   240543960.
  18. ↑ Banfalvi, Gaspar (2021-04-08). "Prebiotic Pathway from Ribose to RNA Formation". International Journal of Molecular Sciences. 22 (8): 3857. doi: 10.3390/ijms22083857 . ISSN   1422-0067. PMC   8068141 . PMID   33917807.
  19. ↑ Bada, Jeffrey L. (2023-04-10). "Volcanic Island lightning prebiotic chemistry and the origin of life in the early Hadean eon". Nature Communications. 14 (1): 2011. Bibcode:2023NatCo..14.2011B. doi:10.1038/s41467-023-37894-y. ISSN   2041-1723. PMC   10086016 . PMID   37037857.
  20. ↑ Kitadai, Norio; Nakamura, Ryuhei; Yamamoto, Masahiro; Takai, Ken; Yoshida, Naohiro; Oono, Yoshi (2019-06-07). "Metals likely promoted protometabolism in early ocean alkaline hydrothermal systems". Science Advances. 5 (6): eaav7848. Bibcode:2019SciA....5.7848K. doi:10.1126/sciadv.aav7848. ISSN   2375-2548. PMC   6584212 . PMID   31223650.
  21. ↑ Smith, Karen E.; House, Christopher H.; Arevalo, Ricardo D.; Dworkin, Jason P.; Callahan, Michael P. (2019-06-25). "Organometallic compounds as carriers of extraterrestrial cyanide in primitive meteorites". Nature Communications. 10 (1): 2777. Bibcode:2019NatCo..10.2777S. doi:10.1038/s41467-019-10866-x. ISSN   2041-1723. PMC   6592946 . PMID   31239434.
  22. ↑ Rimmer, P. B.; Rugheimer, S. (2019-09-01). "Hydrogen cyanide in nitrogen-rich atmospheres of rocky exoplanets". Icarus. 329: 124–131. arXiv: 1902.08022 . Bibcode:2019Icar..329..124R. doi:10.1016/j.icarus.2019.02.020. ISSN   0019-1035. S2CID   119208979.
  23. ↑ Ruiz-Bermejo, Marta; de la Fuente, José Luis; Pérez-Fernández, Cristina; Mateo-Martí, Eva (April 2021). "A Comprehensive Review of HCN-Derived Polymers". Processes. 9 (4): 597. doi: 10.3390/pr9040597 . hdl: 10261/343108 . ISSN   2227-9717.
  24. ↑ Cleaves, H. James (September 2012). "Prebiotic Chemistry: What We Know, What We Don't". Evolution: Education and Outreach. 5 (3): 342–360. doi: 10.1007/s12052-012-0443-9 . ISSN   1936-6434. S2CID   255493640.
  25. 1 2 Deamer, D.; Weber, A. L. (2010-02-01). "Bioenergetics and Life's Origins". Cold Spring Harbor Perspectives in Biology. 2 (2): a004929. doi:10.1101/cshperspect.a004929. ISSN   1943-0264. PMC   2828274 . PMID   20182625.
  26. ↑ Oró, J. (June 1960). "Synthesis of adenine from ammonium cyanide". Biochemical and Biophysical Research Communications. 2 (6): 407–412. doi:10.1016/0006-291x(60)90138-8. ISSN   0006-291X.
  27. ↑ ORÓ, J.; KAMAT, S. S. (April 1961). "Amino-acid Synthesis from Hydrogen Cyanide under Possible Primitive Earth Conditions". Nature. 190 (4774): 442–443. Bibcode:1961Natur.190..442O. doi:10.1038/190442a0. ISSN   0028-0836. PMID   13731262. S2CID   4219284.
  28. ↑ Negrón-Mendoza, A.; Draganić, Z. D.; Navarro-González, R.; Draganić, I. G.; Negron-Mendoza, A.; Draganic, Z. D.; Navarro-Gonzalez, R.; Draganic, I. G. (August 1983). "Aldehydes, Ketones, and Carboxylic Acids Formed Radiolytically in Aqueous Solutions of Cyanides and Simple Nitriles". Radiation Research. 95 (2): 248. Bibcode:1983RadR...95..248N. doi:10.2307/3576253. ISSN   0033-7587. JSTOR   3576253.
  29. 1 2 Das, Tamal; Ghule, Siddharth; Vanka, Kumar (2019-09-25). "Insights Into the Origin of Life: Did It Begin from HCN and H 2 O?". ACS Central Science. 5 (9): 1532–1540. doi:10.1021/acscentsci.9b00520. ISSN   2374-7943. PMC   6764159 . PMID   31572780.
  30. ↑ Wogan, Nicholas F.; Catling, David C.; Zahnle, Kevin J.; Lupu, Roxana (2023-09-01). "Origin-of-life Molecules in the Atmosphere after Big Impacts on the Early Earth". The Planetary Science Journal. 4 (9): 169. arXiv: 2307.09761 . Bibcode:2023PSJ.....4..169W. doi: 10.3847/PSJ/aced83 . ISSN   2632-3338.
  31. 1 2 3 4 Patel, Bhavesh H.; Percivalle, Claudia; Ritson, Dougal J.; Duffy, Colm D.; Sutherland, John D. (April 2015). "Common origins of RNA, protein and lipid precursors in a cyanosulfidic protometabolism". Nature Chemistry. 7 (4): 301–307. Bibcode:2015NatCh...7..301P. doi:10.1038/nchem.2202. ISSN   1755-4330. PMC   4568310 . PMID   25803468.
  32. 1 2 Bizzarri, Bruno Mattia; Saladino, Raffaele; Delfino, Ines; García-Ruiz, Juan Manuel; Di Mauro, Ernesto (2021-01-18). "Prebiotic Organic Chemistry of Formamide and the Origin of Life in Planetary Conditions: What We Know and What Is the Future". International Journal of Molecular Sciences. 22 (2): 917. doi: 10.3390/ijms22020917 . ISSN   1422-0067. PMC   7831497 . PMID   33477625.
  33. ↑ Saladino, Raffaele; Ciambecchini, Umberto; Crestini, Claudia; Costanzo, Giovanna; Negri, Rodolfo; Di Mauro, Ernesto (2003-06-06). "One-Pot TiO 2 -Catalyzed Synthesis of Nucleic Bases and Acyclonucleosides from Formamide: Implications for the Origin of Life". ChemBioChem. 4 (6): 514–521. doi:10.1002/cbic.200300567. ISSN   1439-4227. PMID   12794862. S2CID   2349609.
  34. ↑ Niether, Doreen; Afanasenkau, Dzmitry; Dhont, Jan K. G.; Wiegand, Simone (2016-04-04). "Accumulation of formamide in hydrothermal pores to form prebiotic nucleobases". Proceedings of the National Academy of Sciences. 113 (16): 4272–4277. Bibcode:2016PNAS..113.4272N. doi: 10.1073/pnas.1600275113 . ISSN   0027-8424. PMC   4843465 . PMID   27044100.
  35. ↑ Andersen, Jakob; Andersen, Tommy; Flamm, Christoph; Hanczyc, Martin; Merkle, Daniel; Stadler, Peter (2013-09-25). "Navigating the Chemical Space of HCN Polymerization and Hydrolysis: Guiding Graph Grammars by Mass Spectrometry Data". Entropy. 15 (12): 4066–4083. Bibcode:2013Entrp..15.4066A. doi: 10.3390/e15104066 . ISSN   1099-4300.
  36. ↑ Saladino, Raffaele; Crestini, Claudia; Pino, Samanta; Costanzo, Giovanna; Di Mauro, Ernesto (2012-03-01). "Formamide and the origin of life". Physics of Life Reviews. 9 (1): 84–104. Bibcode:2012PhLRv...9...84S. doi:10.1016/j.plrev.2011.12.002. hdl: 2108/85168 . ISSN   1571-0645. PMID   22196896.
  37. ↑ Koch, Klemens; Schweizer, W. Bernd; Eschenmoser, Albert (April 2007). "Reactions of the HCN-Tetramer with Aldehydes". Chemistry & Biodiversity. 4 (4): 541–553. doi:10.1002/cbdv.200790049. ISSN   1612-1872. PMID   17443870. S2CID   38695557.
  38. ↑ Eschenmoser, Albert (December 2007). "The search for the chemistry of life's origin". Tetrahedron. 63 (52): 12821–12844. doi:10.1016/j.tet.2007.10.012. ISSN   0040-4020.
  39. ↑ Stubbs, R. Trent; Yadav, Mahipal; Krishnamurthy, Ramanarayanan; Springsteen, Greg (November 2020). "A plausible metal-free ancestral analogue of the Krebs cycle composed entirely of α-ketoacids". Nature Chemistry. 12 (11): 1016–1022. Bibcode:2020NatCh..12.1016S. doi:10.1038/s41557-020-00560-7. ISSN   1755-4330. PMC   8570912 . PMID   33046840.
  40. 1 2 Muchowska, Kamila B.; Varma, Sreejith J.; Chevallot-Beroux, Elodie; Lethuillier-Karl, Lucas; Li, Guang; Moran, Joseph (2017-10-02). "Metals promote sequences of the reverse Krebs cycle". Nature Ecology & Evolution. 1 (11): 1716–1721. Bibcode:2017NatEE...1.1716M. doi:10.1038/s41559-017-0311-7. ISSN   2397-334X. PMC   5659384 . PMID   28970480.
  41. 1 2 Mayer, Robert J.; Kaur, Harpreet; Rauscher, Sophia A.; Moran, Joseph (2021-11-03). "Mechanistic Insight into Metal Ion-Catalyzed Transamination". Journal of the American Chemical Society. 143 (45): 19099–19111. doi:10.1021/jacs.1c08535. ISSN   0002-7863. PMID   34730975. S2CID   242937134.
  42. ↑ Mayer, Robert J.; Moran, Joseph (2022-11-25). "Quantifying Reductive Amination in Nonenzymatic Amino Acid Synthesis". Angewandte Chemie International Edition. 61 (48): e202212237. doi:10.1002/anie.202212237. ISSN   1433-7851. PMC   9828492 . PMID   36121198.
  43. ↑ Rauscher, Sophia A.; Moran, Joseph (2022-12-19). "Hydrogen Drives Part of the Reverse Krebs Cycle under Metal or Meteorite Catalysis". Angewandte Chemie International Edition. 61 (51): e202212932. doi:10.1002/anie.202212932. ISSN   1433-7851. PMC   10100321 . PMID   36251920.
  44. ↑ Pinna, Silvana; Kunz, Cäcilia; Halpern, Aaron; Harrison, Stuart A.; Jordan, Sean F.; Ward, John; Werner, Finn; Lane, Nick (2022-10-04). "A prebiotic basis for ATP as the universal energy currency". PLOS Biology. 20 (10): e3001437. doi: 10.1371/journal.pbio.3001437 . ISSN   1545-7885. PMC   9531788 . PMID   36194581.
  45. ↑ "What Is The Metabolism-First Hypothesis For The Origin Of Life? • Stated Clearly". Stated Clearly. Retrieved 2024-01-02.
  46. ↑ Yčas, Martynas (1955-10-15). "A Note on the Origin of Life". Proceedings of the National Academy of Sciences. 41 (10): 714–716. Bibcode:1955PNAS...41..714Y. doi: 10.1073/pnas.41.10.714 . ISSN   0027-8424. PMC   528169 . PMID   16589734.
  47. ↑ Lindahl, Paul A. (August 2004). "Stepwise Evolution of Nonliving to Living Chemical Systems". Origins of Life and Evolution of the Biosphere. 34 (4): 371–389. Bibcode:2004OLEB...34..371L. doi:10.1023/b:orig.0000029880.76881.f5. ISSN   0169-6149. PMID   15279172. S2CID   36069513.
  48. ↑ Yaman, Tolga; Harvey, Jeremy N. (2021-12-04). "Computational Analysis of a Prebiotic Amino Acid Synthesis with Reference to Extant Codon–Amino Acid Relationships". Life. 11 (12): 1343. Bibcode:2021Life...11.1343Y. doi: 10.3390/life11121343 . ISSN   2075-1729. PMC   8707928 . PMID   34947874.
  49. ↑ Sharma, Siddhant; Arya, Aayush; Cruz, Romulo; Cleaves II, Henderson (2021-10-26). "Automated Exploration of Prebiotic Chemical Reaction Space: Progress and Perspectives". Life. 11 (11): 1140. Bibcode:2021Life...11.1140S. doi: 10.3390/life11111140 . ISSN   2075-1729. PMC   8624352 . PMID   34833016.
  50. ↑ Yates, Diana. "Study tracks evolutionary history of metabolic networks". news.illinois.edu. Retrieved 2024-01-02.
  51. ↑ Tessera, Marc (January 2018). "Is pre-Darwinian evolution plausible?". Biology Direct. 13 (1): 18. doi: 10.1186/s13062-018-0216-7 . ISSN   1745-6150. PMC   6151046 . PMID   30241560.
  52. ↑ Kocher, Charles; Dill, Ken A. (January 2023). "Origins of life: first came evolutionary dynamics". QRB Discovery. 4: e4. doi:10.1017/qrd.2023.2. ISSN   2633-2892. PMC   10392681 . PMID   37529034.
  53. ↑ Anet, Frank AL (2004-12-01). "The place of metabolism in the origin of life". Current Opinion in Chemical Biology. 8 (6): 654–659. doi:10.1016/j.cbpa.2004.10.005. ISSN   1367-5931. PMID   15556411.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.