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Farr O, Gaudu N, Danger G, Russell MJ, Ferry D, Nitschke W, Duval S. Methanol on the rocks: green rust transformation promotes the oxidation of methane. J R Soc Interface 2023; 20:20230386. [PMID: 37727071 PMCID: PMC10509593 DOI: 10.1098/rsif.2023.0386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 08/30/2023] [Indexed: 09/21/2023] Open
Abstract
Shared coordination geometries between metal ions within reactive minerals and enzymatic metal cofactors hints at mechanistic and possibly evolutionary homology between particular abiotic chemical mineralogies and biological metabolism. The octahedral coordination of reactive Fe2+/3+ minerals such as green rusts, endemic to anoxic sediments and the early Earth's oceans, mirrors the di-iron reaction centre of soluble methane monooxygenase (sMMO), responsible for methane oxidation in methanotrophy. We show that methane oxidation occurs in tandem with the oxidation of green rust to lepidocrocite and magnetite, mimicking radical-mediated methane oxidation found in sMMO to yield not only methanol but also halogenated hydrocarbons in the presence of seawater. This naturally occurring geochemical pathway for CH4 oxidation elucidates a previously unidentified carbon cycling mechanism in modern and ancient environments and reveals clues into mineral-mediated reactions in the synthesis of organic compounds necessary for the emergence of life.
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Affiliation(s)
- Orion Farr
- CNRS, CINaM, Aix-Marseille Univ, 13009 Marseille, France
- CNRS, BIP (UMR 7281), Aix Marseille Univ, Marseille, France
| | - Nil Gaudu
- CNRS, BIP (UMR 7281), Aix Marseille Univ, Marseille, France
| | | | | | - Daniel Ferry
- CNRS, CINaM, Aix-Marseille Univ, 13009 Marseille, France
| | | | - Simon Duval
- CNRS, BIP (UMR 7281), Aix Marseille Univ, Marseille, France
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Russell MJ. A self-sustaining serpentinization mega-engine feeds the fougerite nanoengines implicated in the emergence of guided metabolism. Front Microbiol 2023; 14:1145915. [PMID: 37275164 PMCID: PMC10236563 DOI: 10.3389/fmicb.2023.1145915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 03/22/2023] [Indexed: 06/07/2023] Open
Abstract
The demonstration by Ivan Barnes et al. that the serpentinization of fresh Alpine-type ultramafic rocks results in the exhalation of hot alkaline fluids is foundational to the submarine alkaline vent theory (AVT) for life's emergence to its 'improbable' thermodynamic state. In AVT, such alkaline fluids ≤ 150°C, bearing H2 > CH4 > HS--generated and driven convectively by a serpentinizing exothermic mega-engine operating in the ultramafic crust-exhale into the iron-rich, CO2> > > NO3--bearing Hadean ocean to result in hydrothermal precipitate mounds comprising macromolecular ferroferric-carbonate oxyhydroxide and minor sulfide. As the nanocrystalline minerals fougerite/green rust and mackinawite (FeS), they compose the spontaneously precipitated inorganic membranes that keep the highly contrasting solutions apart, thereby maintaining redox and pH disequilibria. They do so in the form of fine chimneys and chemical gardens. The same disequilibria drive the reduction of CO2 to HCOO- or CO, and the oxidation of CH4 to a methyl group-the two products reacting to form acetate in a sequence antedating the 'energy-producing' acetyl coenzyme-A pathway. Fougerite is a 2D-layered mineral in which the hydrous interlayers themselves harbor 2D solutions, in effect constricted to ~ 1D by preferentially directed electron hopping/tunneling, and proton Gröthuss 'bucket-brigading' when subject to charge. As a redox-driven nanoengine or peristaltic pump, fougerite forces the ordered reduction of nitrate to ammonium, the amination of pyruvate and oxalate to alanine and glycine, and their condensation to short peptides. In turn, these peptides have the flexibility to sequester the founding inorganic iron oxyhydroxide, sulfide, and pyrophosphate clusters, to produce metal- and phosphate-dosed organic films and cells. As the feed to the hydrothermal mound fails, the only equivalent sustenance on offer to the first autotrophs is the still mildly serpentinizing upper crust beneath. While the conditions here are very much less bountiful, they do offer the similar feed and disequilibria the survivors are accustomed to. Sometime during this transition, a replicating non-ribosomal guidance system is discovered to provide the rules to take on the incrementally changing surroundings. The details of how these replicating apparatuses emerged are the hard problem, but by doing so the progenote archaea and bacteria could begin to colonize what would become the deep biosphere. Indeed, that the anaerobic nitrate-respiring methanotrophic archaea and the deep-branching Acetothermia presently comprise a portion of that microbiome occupying serpentinizing rocks offers circumstantial support for this notion. However, the inescapable, if jarring conclusion is drawn that, absent fougerite/green rust, there would be no structured channelway to life.
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Affiliation(s)
- Michael J. Russell
- Dipartimento di Chimica, Università degli Studi di Torino, Torino, Italy
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Nitschke W, Schoepp‐Cothenet B, Duval S, Zuchan K, Farr O, Baymann F, Panico F, Minguzzi A, Branscomb E, Russell MJ. Aqueous electrochemistry: The toolbox for life's emergence from redox disequilibria. Electrochemical Science Adv 2022. [DOI: 10.1002/elsa.202100192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
| | | | - Simon Duval
- CNRS, BIP (UMR 7281), Aix Marseille Univ Marseille France
| | - Kilian Zuchan
- CNRS, BIP (UMR 7281), Aix Marseille Univ Marseille France
| | - Orion Farr
- CNRS, BIP (UMR 7281), Aix Marseille Univ Marseille France
- Aix Marseille Univ CINaM (UMR 7325) Luminy France
| | - Frauke Baymann
- CNRS, BIP (UMR 7281), Aix Marseille Univ Marseille France
| | - Francesco Panico
- Dipartimento di Chimica Università degli Studi di Milano Milan Italy
| | | | - Elbert Branscomb
- Department of Physics Carl R. Woese Institute for Genomic Biology, University of Illinois Urbana Illinois USA
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Russell MJ, Young S, Martin R, Harman R. Surgical management of Graves' disease: historical context and single institution experience. N Z Med J 2022; 135:43-49. [PMID: 35728139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
AIM To describe indications and outcomes of total thyroidectomy for Graves' disease in a large New Zealand endocrine surgery unit, and to compare these results to international studies. METHODS We analysed a prospectively collected database to describe the indications and outcomes of surgery for Graves' disease between December 2001 and January 2021. RESULTS Among 64 patients who underwent total thyroidectomy at our tertiary centre for Graves' hyperthyroidism, Graves' ophthalmopathy and patient preference/aversion to radioactive iodine were the most common indications for surgery. Total thyroidectomy resulted in long-term control of thyrotoxicosis in all patients. There were no incidences of recurrent laryngeal nerve injury. One patient (1.6%) suffered permanent hypoparathyroidism. CONCLUSION Total thyroidectomy is a safe and effective treatment for Graves' disease. In our population, total thyroidectomy functions as a second-line treatment for Graves' disease.
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Affiliation(s)
- Michael J Russell
- FRACS, Breast and Endocrine Surgery Fellow, Department of General Surgery, Waitematā DHB, Auckland
| | - Simon Young
- FRACP, Endocrinologist, Department of Medicine, Waitemata DHB, Auckland
| | - Richard Martin
- FRACS, Cutaneous Surgical Oncologist, Head and Neck and General Surgeon, Department of General Surgery, Waitematā DHB, Auckland
| | - Richard Harman
- FRACS, Breast, Endocrine, Laparoscopic and Melanoma Surgeon, Department of General Surgery, Waitematā DHB, Auckland
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Cavalazzi B, Lemelle L, Simionovici A, Cady SL, Russell MJ, Bailo E, Canteri R, Enrico E, Manceau A, Maris A, Salomé M, Thomassot E, Bouden N, Tucoulou R, Hofmann A. Cellular remains in a ~3.42-billion-year-old subseafloor hydrothermal environment. Sci Adv 2021; 7:eabf3963. [PMID: 34261651 PMCID: PMC8279515 DOI: 10.1126/sciadv.abf3963] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 05/28/2021] [Indexed: 05/15/2023]
Abstract
Subsurface habitats on Earth host an extensive extant biosphere and likely provided one of Earth's earliest microbial habitats. Although the site of life's emergence continues to be debated, evidence of early life provides insights into its early evolution and metabolic affinity. Here, we present the discovery of exceptionally well-preserved, ~3.42-billion-year-old putative filamentous microfossils that inhabited a paleo-subseafloor hydrothermal vein system of the Barberton greenstone belt in South Africa. The filaments colonized the walls of conduits created by low-temperature hydrothermal fluid. Combined with their morphological and chemical characteristics as investigated over a range of scales, they can be considered the oldest methanogens and/or methanotrophs that thrived in an ultramafic volcanic substrate.
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Affiliation(s)
- Barbara Cavalazzi
- Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Università di Bologna, Bologna, Italy.
- Department of Geology, University of Johannesburg, Johannesburg, South Africa
| | | | - Alexandre Simionovici
- ISTerre, University of Grenoble-Alpes, CNRS, Grenoble, France
- Institut Universitaire de France, Paris, France
| | - Sherry L Cady
- Pacific Northwest National Laboratory, EMSL, Richland, WA, USA
| | - Michael J Russell
- Dipartimento di Chimica, Università degli Studi di Torino, Torino, Italy
| | | | | | - Emanuele Enrico
- INRiM, Istituto Nazionale di Ricerca Metrologica, Torino, Italy
| | - Alain Manceau
- ISTerre, University of Grenoble-Alpes, CNRS, Grenoble, France
| | - Assimo Maris
- Dipartimento di Chimica "Giacomo Ciamician," Università di Bologna, Bologna, Italy
| | | | | | | | - Rémi Tucoulou
- European Synchrotron Radiation Facility, Grenoble, France
| | - Axel Hofmann
- Department of Geology, University of Johannesburg, Johannesburg, South Africa
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Russell MJ. The "Water Problem"( sic), the Illusory Pond and Life's Submarine Emergence-A Review. Life (Basel) 2021; 11:429. [PMID: 34068713 PMCID: PMC8151828 DOI: 10.3390/life11050429] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 04/30/2021] [Accepted: 05/01/2021] [Indexed: 01/10/2023] Open
Abstract
The assumption that there was a "water problem" at the emergence of life-that the Hadean Ocean was simply too wet and salty for life to have emerged in it-is here subjected to geological and experimental reality checks. The "warm little pond" that would take the place of the submarine alkaline vent theory (AVT), as recently extolled in the journal Nature, flies in the face of decades of geological, microbiological and evolutionary research and reasoning. To the present author, the evidence refuting the warm little pond scheme is overwhelming given the facts that (i) the early Earth was a water world, (ii) its all-enveloping ocean was never less than 4 km deep, (iii) there were no figurative "Icelands" or "Hawaiis", nor even an "Ontong Java" then because (iv) the solidifying magma ocean beneath was still too mushy to support such salient loadings on the oceanic crust. In place of the supposed warm little pond, we offer a well-protected mineral mound precipitated at a submarine alkaline vent as life's womb: in place of lipid membranes, we suggest peptides; we replace poisonous cyanide with ammonium and hydrazine; instead of deleterious radiation we have the appropriate life-giving redox and pH disequilibria; and in place of messy chemistry we offer the potential for life's emergence from the simplest of geochemically available molecules and ions focused at a submarine alkaline vent in the Hadean-specifically within the nano-confined flexible and redox active interlayer walls of the mixed-valent double layer oxyhydroxide mineral, fougerite/green rust comprising much of that mound.
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Affiliation(s)
- Michael J Russell
- Dipartimento di Chimica, Università degli Studi di Torino, via P. Giuria 7, 10125 Turin, Italy
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Russell MJ, Ponce A. Six 'Must-Have' Minerals for Life's Emergence: Olivine, Pyrrhotite, Bridgmanite, Serpentine, Fougerite and Mackinawite. Life (Basel) 2020; 10:E291. [PMID: 33228029 PMCID: PMC7699418 DOI: 10.3390/life10110291] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/13/2020] [Accepted: 11/14/2020] [Indexed: 12/25/2022] Open
Abstract
Life cannot emerge on a planet or moon without the appropriate electrochemical disequilibria and the minerals that mediate energy-dissipative processes. Here, it is argued that four minerals, olivine ([Mg>Fe]2SiO4), bridgmanite ([Mg,Fe]SiO3), serpentine ([Mg,Fe,]2-3Si2O5[OH)]4), and pyrrhotite (Fe(1-x)S), are an essential requirement in planetary bodies to produce such disequilibria and, thereby, life. Yet only two minerals, fougerite ([Fe2+6xFe3+6(x-1)O12H2(7-3x)]2+·[(CO2-)·3H2O]2-) and mackinawite (Fe[Ni]S), are vital-comprising precipitate membranes-as initial "free energy" conductors and converters of such disequilibria, i.e., as the initiators of a CO2-reducing metabolism. The fact that wet and rocky bodies in the solar system much smaller than Earth or Venus do not reach the internal pressure (≥23 GPa) requirements in their mantles sufficient for producing bridgmanite and, therefore, are too reduced to stabilize and emit CO2-the staple of life-may explain the apparent absence or negligible concentrations of that gas on these bodies, and thereby serves as a constraint in the search for extraterrestrial life. The astrobiological challenge then is to search for worlds that (i) are large enough to generate internal pressures such as to produce bridgmanite or (ii) boast electron acceptors, including imported CO2, from extraterrestrial sources in their hydrospheres.
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Affiliation(s)
- Michael J. Russell
- Dipartimento di Chimica, Università degli Studi di Torino, via P. Giuria 7, 10125 Turin, Italy
| | - Adrian Ponce
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA;
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White LM, Shibuya T, Vance SD, Christensen LE, Bhartia R, Kidd R, Hoffmann A, Stucky GD, Kanik I, Russell MJ. Simulating Serpentinization as It Could Apply to the Emergence of Life Using the JPL Hydrothermal Reactor. Astrobiology 2020; 20:307-326. [PMID: 32125196 DOI: 10.1089/ast.2018.1949] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The molecules feeding life's emergence are thought to have been provided through the hydrothermal interactions of convecting carbonic ocean waters with minerals comprising the early Hadean oceanic crust. Few laboratory experiments have simulated ancient hydrothermal conditions to test this conjecture. We used the JPL hydrothermal flow reactor to investigate CO2 reduction in simulated ancient alkaline convective systems over 3 days (T = 120°C, P = 100 bar, pH = 11). H2-rich hydrothermal simulant and CO2-rich ocean simulant solutions were periodically driven in 4-h cycles through synthetic mafic and ultramafic substrates and Fe>Ni sulfides. The resulting reductants included micromoles of HS- and formate accompanied possibly by micromoles of acetate and intermittent minor bursts of methane as ascertained by isotopic labeling. The formate concentrations directly correlated with the CO2 input as well as with millimoles of Mg2+ ions, whereas the acetate did not. Also, tens of micromoles of methane were drawn continuously from the reactor materials during what appeared to be the onset of serpentinization. These results support the hypothesis that formate may have been delivered directly to a branch of an emerging acetyl coenzyme-A pathway, thus obviating the need for the very first hydrogenation of CO2 to be made in a hydrothermal mound. Another feed to early metabolism could have been methane, likely mostly leached from primary CH4 present in the original Hadean crust or emanating from the mantle. That a small volume of methane was produced sporadically from the 13CO2-feed, perhaps from transient occlusions, echoes the mixed results and interpretations from other laboratories. As serpentinization and hydrothermal leaching can occur wherever an ocean convects within anhydrous olivine- and sulfide-rich crust, these results may be generalized to other wet rocky planets and moons in our solar system and beyond.
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Affiliation(s)
- Lauren M White
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California
- Project Systems Engineering, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Takazo Shibuya
- Department of Subsurface Geobiological Analysis and Research (D-SUGAR), Project Team for Development of New-generation Research Protocol for Submarine Resources, and Research and Development (RandD), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
- Research and Development (RandD) Center for Submarine Resources, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka, Japan
| | - Steven D Vance
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Lance E Christensen
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Rohit Bhartia
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Richard Kidd
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Adam Hoffmann
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Galen D Stucky
- Department of Chemistry and Biochemistry, University of California at Santa Barbara, Santa Barbara, California
- Materials Department, University of California at Santa Barbara, Santa Barbara, California
| | - Isik Kanik
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Michael J Russell
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
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Branscomb E, Russell MJ. Correction to 'On the beneficent thickness of water'. Interface Focus 2020; 10:20190113. [PMID: 31897296 DOI: 10.1098/rsfs.2019.0113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
[This corrects the article DOI: 10.1098/rsfs.2019.0061.].
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Cardoso SSS, Cartwright JHE, Čejková J, Cronin L, De Wit A, Giannerini S, Horváth D, Rodrigues A, Russell MJ, Sainz-Díaz CI, Tóth Á. Chemobrionics: From Self-Assembled Material Architectures to the Origin of Life. Artif Life 2020; 26:315-326. [PMID: 32697160 DOI: 10.1162/artl_a_00323] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Self-organizing precipitation processes, such as chemical gardens forming biomimetic micro- and nanotubular forms, have the potential to show us new fundamental science to explore, quantify, and understand nonequilibrium physicochemical systems, and shed light on the conditions for life's emergence. The physics and chemistry of these phenomena, due to the assembly of material architectures under a flux of ions, and their exploitation in applications, have recently been termed chemobrionics. Advances in understanding in this area require a combination of expertise in physics, chemistry, mathematical modeling, biology, and nanoengineering, as well as in complex systems and nonlinear and materials sciences, giving rise to this new synergistic discipline of chemobrionics.
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Affiliation(s)
- Silvana S S Cardoso
- University of Cambridge, Department of Chemical Engineering and Biotechnology.
| | - Julyan H E Cartwright
- Universidad de Granada CSIC, Instituto Andaluz de Ciencias de la Tierra, Instituto Carlos I de Física Teórica y Computacional.
| | - Jitka Čejková
- University of Chemistry and Technology Prague, Department of Chemical Engineering
| | | | - Anne De Wit
- Université Libre de Bruxelles (ULB), Nonlinear Physical Chemistry Unit
| | - Simone Giannerini
- Università di Bologna, Dipartimento di Scienze Statistiche "Paolo Fortunati"
| | - Dezső Horváth
- University of Szeged, Department of Applied and Environmental Chemistry
| | | | | | | | - Ágota Tóth
- University of Szeged, Department of Physical Chemistry and Materials Science
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Abstract
Books with titles like 'The Call of the Wild' seemed to set a path for a life. Thus, I would be an explorer-a plan that did not work out so well, at least at first. On leaving school I got a job as a 'Works Chemist Improver', testing Ni catalysts for the hydrogenation of phenol to cyclohexanol. Taking night classes I passed enough exams to study geology at Queen Mary College, London. Armed thus I travelled to the Solomon Islands where geology is a 'happening'! Next was Canada to visit a mine sunk into a 1.5 billion year old Pb-Zn orebody precipitated from submarine hot springs. At last I reached the Yukon to prospect for silver. Thence to Ireland researching what I also took to be 'exhalative' (i.e. hot spring-related) Pb-Zn orebodies. While there in 1979, the discovery of 350°C metal-bearing acidic waters issuing from submarine Black Smoker chimneys in the Pacific sent us searching for fossil examples in the Irish mines. However, the chimneys we found were more like chemical gardens than Black Smokers, a finding that made us think about the emergence of life. After all, what better for life's emergence than to have a membrane comprising Fe minerals dosed with Ni in our chimneys to mediate the 'hydrogenation' of CO2-life's job anyway. Indeed, such a membrane would keep redox and pH disequilibria at bay, just like biological membranes. At the same time, my field research among Alpine ophiolites-ocean floor mafic rocks obducted to the Alps-indicated that alkaline waters bearing H2 and CH4 were a result of serpentinization, a process that must have operated in all ocean floors over all time. Thus it was that we could predict the Lost City hydrothermal field 10 years before its discovery in the North Atlantic in the year 2000. Lost City comprises a number of alkaline springs at up to 90°C that produce carbonate and brucite (Mg[OH]2) chimneys. We had surmised that Ni-enriched FeS chimneys would have precipitated at comparable alkaline springs issuing into a metal-rich carbonic ocean on the very early Earth (inducing membrane potentials comparable to those capable of succouring all life, and presumably, sufficient to drive life into being). However, our laboratory precipitates also revealed green rust, thought to be the precursor to the magnetite now comprising the Archaean Banded Iron Formations. We now look upon green rust, also known as fougèrite, as the tangible, base fractal of life.
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Affiliation(s)
- Michael J. Russell
- NASA Astrobiology Institute, NASA Ames Research Center, Moffett Field, CA, USA
- http://bip.cnrs-mrs.fr/bip09/AHVics.html
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Cartwright JHE, Russell MJ. The origin of life: the submarine alkaline vent theory at 30. Interface Focus 2019; 9:20190104. [PMCID: PMC6802131 DOI: 10.1098/rsfs.2019.0104] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 09/12/2019] [Indexed: 11/12/2023] Open
Affiliation(s)
- Julyan H. E. Cartwright
- Instituto Andaluz de Ciencias de la Tierra, CSIC–Universidad de Granada, 18100 Armilla, Granada, Spain
- Instituto Carlos I de Física Teórica y Computacional, Universidad de Granada, 18071 Granada, Spain
| | - Michael J. Russell
- NASA Astrobiology Institute, NASA Ames Research Center California, CA, USA
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Duval S, Baymann F, Schoepp-Cothenet B, Trolard F, Bourrié G, Grauby O, Branscomb E, Russell MJ, Nitschke W. Fougerite: the not so simple progenitor of the first cells. Interface Focus 2019; 9:20190063. [PMID: 31641434 DOI: 10.1098/rsfs.2019.0063] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2019] [Indexed: 12/22/2022] Open
Abstract
We here review the extraordinary mineralogical properties of green rusts and their naturally occurring form, fougerite, and discuss the pertinence of these properties within the alkaline hydrothermal vent (AHV) hypothesis for life's emergence. We put forward an extended version of the AHV scenario which enhances the conformity between extant life and its earliest progenitor by extensively making use of fougerite's mechanistic and catalytic particularities.
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Affiliation(s)
- Simon Duval
- Aix Marseille Université, CNRS, BIP (UMR 7281), Marseille, France
| | - Frauke Baymann
- Aix Marseille Université, CNRS, BIP (UMR 7281), Marseille, France
| | | | | | | | - Olivier Grauby
- Aix Marseille Université, CINaM (UMR 7325), Luminy, France
| | - Elbert Branscomb
- Carl R. Woese Institute for Genomic Biology, and Department of Physics, University of Illinois, Urbana, IL 61801, USA
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14
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Branscomb E, Russell MJ. Why the Submarine Alkaline Vent is the Most Reasonable Explanation for the Emergence of Life. Bioessays 2018; 41:e1800208. [PMID: 30431168 DOI: 10.1002/bies.201800208] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Elbert Branscomb
- University of Illinois, Urbana-Champaign, Carl R. Woese Institute for Genomic Biology, and Department of Physics, 3406 IGB, MC-195, 1206 W. Gregory Drive, Urbana, Illinois
| | - Michael J Russell
- California Institute of Technology, JPL/NASA, 4800 Oak Grove Drive, M/S 183-601, Pasadena, California
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Abstract
Korenaga and coworkers presented evidence to suggest that the Earth's mantle was dry and water filled the ocean to twice its present volume 4.3 billion years ago. Carbon dioxide was constantly exhaled during the mafic to ultramafic volcanic activity associated with magmatic plumes that produced the thick, dense, and relatively stable oceanic crust. In that setting, two distinct and major types of sub-marine hydrothermal vents were active: ~400 °C acidic springs, whose effluents bore vast quantities of iron into the ocean, and ~120 °C, highly alkaline, and reduced vents exhaling from the cooler, serpentinizing crust some distance from the heads of the plumes. When encountering the alkaline effluents, the iron from the plume head vents precipitated out, forming mounds likely surrounded by voluminous exhalative deposits similar to the banded iron formations known from the Archean. These mounds and the surrounding sediments, comprised micro or nano-crysts of the variable valence FeII/FeIII oxyhydroxide known as green rust. The precipitation of green rust, along with subsidiary iron sulfides and minor concentrations of nickel, cobalt, and molybdenum in the environment at the alkaline springs, may have established both the key bio-syntonic disequilibria and the means to properly make use of them-the elements needed to effect the essential inanimate-to-animate transitions that launched life. Specifically, in the submarine alkaline vent model for the emergence of life, it is first suggested that the redox-flexible green rust micro- and nano-crysts spontaneously precipitated to form barriers to the complete mixing of carbonic ocean and alkaline hydrothermal fluids. These barriers created and maintained steep ionic disequilibria. Second, the hydrous interlayers of green rust acted as engines that were powered by those ionic disequilibria and drove essential endergonic reactions. There, aided by sulfides and trace elements acting as catalytic promoters and electron transfer agents, nitrate could be reduced to ammonia and carbon dioxide to formate, while methane may have been oxidized to methyl and formyl groups. Acetate and higher carboxylic acids could then have been produced from these C1 molecules and aminated to amino acids, and thence oligomerized to offer peptide nests to phosphate and iron sulfides, and secreted to form primitive amyloid-bounded structures, leading conceivably to protocells.
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Affiliation(s)
- Michael J Russell
- Planetary Chemistry and Astrobiology, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA.
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Branscomb E, Russell MJ. Frankenstein or a Submarine Alkaline Vent: Who is Responsible for Abiogenesis? Bioessays 2018; 40:e1700182. [DOI: 10.1002/bies.201700182] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 04/26/2018] [Indexed: 12/18/2022]
Affiliation(s)
- Elbert Branscomb
- Department of Physics; Carl R. Woese Institute for Genomic Biology; University of Illinois; Urbana IL 61801 USA
| | - Michael J. Russell
- Planetary Chemistry and Astrobiology; Sec. 3225 MS:183-301; Jet Propulsion Laboratory; California Institute of Technology; Pasadena CA 91109-8099 USA
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17
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Baymann F, Schoepp-Cothenet B, Duval S, Guiral M, Brugna M, Baffert C, Russell MJ, Nitschke W. On the Natural History of Flavin-Based Electron Bifurcation. Front Microbiol 2018; 9:1357. [PMID: 30018596 PMCID: PMC6037941 DOI: 10.3389/fmicb.2018.01357] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 06/05/2018] [Indexed: 11/23/2022] Open
Abstract
Electron bifurcation is here described as a special case of the continuum of electron transfer reactions accessible to two-electron redox compounds with redox cooperativity. We argue that electron bifurcation is foremost an electrochemical phenomenon based on (a) strongly inverted redox potentials of the individual redox transitions, (b) a high endergonicity of the first redox transition, and (c) an escapement-type mechanism rendering completion of the first electron transfer contingent on occurrence of the second one. This mechanism is proposed to govern both the traditional quinone-based and the newly discovered flavin-based versions of electron bifurcation. Conserved and variable aspects of the spatial arrangement of electron transfer partners in flavoenzymes are assayed by comparing the presently available 3D structures. A wide sample of flavoenzymes is analyzed with respect to conserved structural modules and three major structural groups are identified which serve as basic frames for the evolutionary construction of a plethora of flavin-containing redox enzymes. We argue that flavin-based and other types of electron bifurcation are of primordial importance to free energy conversion, the quintessential foundation of life, and discuss a plausible evolutionary ancestry of the mechanism.
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Affiliation(s)
- Frauke Baymann
- CNRS, BIP, UMR 7281, IMM FR3479, Aix-Marseille University, Marseille, France
| | | | - Simon Duval
- CNRS, BIP, UMR 7281, IMM FR3479, Aix-Marseille University, Marseille, France
| | - Marianne Guiral
- CNRS, BIP, UMR 7281, IMM FR3479, Aix-Marseille University, Marseille, France
| | - Myriam Brugna
- CNRS, BIP, UMR 7281, IMM FR3479, Aix-Marseille University, Marseille, France
| | - Carole Baffert
- CNRS, BIP, UMR 7281, IMM FR3479, Aix-Marseille University, Marseille, France
| | - Michael J. Russell
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States
| | - Wolfgang Nitschke
- CNRS, BIP, UMR 7281, IMM FR3479, Aix-Marseille University, Marseille, France
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Branscomb E, Russell MJ. Frankenstein or a Submarine Alkaline Vent: Who Is Responsible for Abiogenesis?: Part 1: What is life-that it might create itself? Bioessays 2018; 40:e1700179. [PMID: 29870581 DOI: 10.1002/bies.201700179] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 04/16/2018] [Indexed: 12/13/2022]
Abstract
Origin of life models based on "energized assemblages of building blocks" are untenable in principle. This is fundamentally a consequence of the fact that any living system is in a physical state that is extremely far from equilibrium, a condition it must itself build and sustain. This in turn requires that it carries out all of its molecular transformations-obligatorily those that convert, and thereby create, disequilibria-using case-specific mechanochemical macromolecular machines. Mass-action solution chemistry is quite unable to do this. We argue in Part 2 of this series that this inherent dependence of life on disequilibria-converting macromolecular machines is also an obligatory requirement for life at its emergence. Therefore, life must have been launched by the operation of abiotic macromolecular machines driven by abiotic, but specifically "life-like", disequilibria, coopted from mineral precipitates that are chemically and physically active. Models grounded in "chemistry-in-a-bag" ideas, however energized, should not be considered.
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Affiliation(s)
- Elbert Branscomb
- Carl R. Woese Institute for Genomic Biology and Department of Physics, University of Illinois, Urbana, IL, 61801, USA
| | - Michael J Russell
- Planetary Chemistry and Astrobiology, Jet Propulsion Laboratory California Institute of Technology, Pasadena, CA, 91109-8099, USA
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19
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Jay SM, Russell MJ, Lau YC, Dunn JW, Roberts R. Ingested bread clip as an unexpected diagnostic tool. N Z Med J 2018; 131:90-96. [PMID: 29565940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We describe a case where a bread clip has in fact became lodged adjacent to a portion of small bowel affected by a deposit of previously undiagnosed metastatic serous carcinoma of likely ovarian origin.
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Affiliation(s)
- Sharon M Jay
- Department of General Surgery, Christchurch Hospital, Christchurch
| | | | - Yee C Lau
- Department of General Surgery, Christchurch Hospital, Christchurch
| | - Joel W Dunn
- Department of Radiology, Christchurch Hospital, Christchurch
| | - Ross Roberts
- Department of General Surgery, Christchurch Hospital, Christchurch
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20
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Russell MJ, Hamer PW, Roberts RH. Oesophageal adenocarcinoma associated with a right-sided aortic arch. ANZ J Surg 2017; 89:127-129. [PMID: 29194894 DOI: 10.1111/ans.14127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Revised: 05/10/2017] [Accepted: 06/01/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Michael J Russell
- Department of General Surgery, Christchurch Hospital, Christchurch, New Zealand
| | - Peter W Hamer
- Department of General Surgery, Christchurch Hospital, Christchurch, New Zealand
| | - Ross H Roberts
- Department of General Surgery, Christchurch Hospital, Christchurch, New Zealand
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21
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Russell MJ, Murray AE, Hand KP. The Possible Emergence of Life and Differentiation of a Shallow Biosphere on Irradiated Icy Worlds: The Example of Europa. Astrobiology 2017; 17:1265-1273. [PMID: 29016193 PMCID: PMC5729856 DOI: 10.1089/ast.2016.1600] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 04/28/2017] [Indexed: 05/17/2023]
Abstract
Irradiated ice-covered ocean worlds with rocky mafic mantles may provide the conditions needed to drive the emergence and maintenance of life. Alkaline hydrothermal springs-relieving the geophysical, thermal, and chemical disequilibria between oceans and tidally stressed crusts-could generate inorganic barriers to the otherwise uncontrolled and kinetically disfavored oxidation of hydrothermal hydrogen and methane. Ionic gradients imposed across these inorganic barriers, comprising iron oxyhydroxides and sulfides, could drive the hydrogenation of carbon dioxide and the oxidation of methane through thermodynamically favorable metabolic pathways leading to early life-forms. In such chemostatic environments, fuels may eventually outweigh oxidants. Ice-covered oceans are primarily heated from below, creating convection that could transport putative microbial cells and cellular cooperatives upward to congregate beneath an ice shell, potentially giving rise to a highly focused shallow biosphere. It is here where electron acceptors, ultimately derived from the irradiated surface, could be delivered to such life-forms through exchange with the icy surface. Such zones would act as "electron disposal units" for the biosphere, and occupants might be transferred toward the surface by buoyant diapirs and even entrained into plumes. Key Words: Biofilms-Europa-Extraterrestrial life-Hydrothermal systems. Astrobiology 17, 1265-1273.
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Affiliation(s)
- Michael J. Russell
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Alison E. Murray
- Division of Earth and Ecosystem Sciences, Desert Research Institute, Reno, Nevada
| | - Kevin P. Hand
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
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22
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Wong ML, Charnay BD, Gao P, Yung YL, Russell MJ. Nitrogen Oxides in Early Earth's Atmosphere as Electron Acceptors for Life's Emergence. Astrobiology 2017; 17:975-983. [PMID: 29023147 DOI: 10.1089/ast.2016.1473] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We quantify the amount of nitrogen oxides (NOx) produced through lightning and photochemical processes in the Hadean atmosphere to be available in the Hadean ocean for the emergence of life. Atmospherically generated nitrate (NO3-) and nitrite (NO2-) are the most attractive high-potential electron acceptors for pulling and enabling crucial redox reactions of autotrophic metabolic pathways at submarine alkaline hydrothermal vents. The Hadean atmosphere, dominated by CO2 and N2, will produce nitric oxide (NO) when shocked by lightning. Photochemical reactions involving NO and H2O vapor will then produce acids such as HNO, HNO2, HNO3, and HO2NO2 that rain into the ocean. There, they dissociate into or react to form nitrate and nitrite. We present new calculations based on a novel combination of early-Earth global climate model and photochemical modeling, and we predict the flux of NOx to the Hadean ocean. In our 0.1-, 1-, and 10-bar pCO2 models, we calculate the NOx delivery to be 2.4 × 105, 6.5 × 108, and 1.9 × 108 molecules cm-2 s-1. After only tens of thousands to tens of millions of years, these NOx fluxes are expected to produce sufficient (micromolar) ocean concentrations of high-potential electron acceptors for the emergence of life. Key Words: Nitrogen oxides-Nitrate-Nitrite-Photochemistry-Lightning-Emergence of life. Astrobiology 17, 975-983.
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Affiliation(s)
- Michael L Wong
- 1 Division of Geological and Planetary Sciences, California Institute of Technology , Pasadena, California
| | - Benjamin D Charnay
- 2 LESIA, Observatoire de Paris, PSL Research University , CNRS, Sorbonne Universités, UPMC Univ. Paris 06, Univ. Paris Diderot, Sorbonne Paris Cité, Meudon, France
- 3 Virtual Planetary Laboratory, University of Washington , Seattle, Washington
| | - Peter Gao
- 4 Department of Astronomy, University of California Berkeley , Berkeley, California
| | - Yuk L Yung
- 1 Division of Geological and Planetary Sciences, California Institute of Technology , Pasadena, California
- 5 Jet Propulsion Laboratory, California Institute of Technology , Pasadena, California
| | - Michael J Russell
- 5 Jet Propulsion Laboratory, California Institute of Technology , Pasadena, California
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Abstract
As many of the methanogens first encountered at hydrothermal vents were thermophilic to hyperthermophilic and comprised one of the lower roots of the evolutionary tree, it has been assumed that methanogenesis was one of the earliest, if not the earliest, pathway to life. It being well known that hydrothermal springs associated with serpentinization also bore abiotic methane, it had been further assumed that emergent biochemistry merely adopted and quickened this supposed serpentinization reaction. Yet, recent hydrothermal experiments simulating serpentinization have failed to generate methane so far, thus casting doubt on this assumption. The idea that the inverse view is worthy of debate, that is, that methanotrophy was the earlier, is stymied by the "fact" that methanotrophy itself has been termed "reverse methanogenesis," so allotting the methanogens the founding pedigree. Thus, attempting to suggest instead that methanogenesis might be termed reverse methanotrophy would require "unlearning"-a challenge to the subconscious! Here we re-examine the "impossibility" of methanotrophy predating methanogenesis as in what we have termed the "denitrifying methanotrophic acetogenic pathway." Advantages offered by such thinking are that methane would not only be a fuel but also a ready source of reduced carbon to combine with formate or carbon monoxide-available in hydrothermal fluids-to generate acetate, a target molecule of the first autotrophs. And the nitrate/nitrite required for the putative oxidation of methane with activated NO would also be a ready source of fixed nitrogen for amination reactions. Theoretical conditions for such a putative pathway would be met in a hydrothermal green rust-bearing exhalative pile and associated chimneys subject to proton and electron counter gradients. This hypothesis could be put to test in a high-pressure hydrothermal reaction chamber in which a cool carbonate/nitrate/nitrite-bearing early acidulous ocean simulant is juxtaposed across a precipitate membrane to an alkaline solution of hydrogen and methane. Key Words: Green rust-Methanotrophy-Nitrate reduction-Emergence of life. Astrobiology 17, 1053-1066.
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Affiliation(s)
- Michael J. Russell
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Wolfgang Nitschke
- CNRS/Aix-Marseille University, BIP UMR 7281, IMM FR 3479, Marseille, France
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24
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Rogers JE, Russell MJ, Harwell MC. Improved method for calibration of exchange flows for a physical transport box model of Tampa Bay, FL USA. J Coast Res 2017; 33:972-988. [PMID: 34316092 PMCID: PMC8312576 DOI: 10.2112/jcoastres-d-16-00077.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
We report the results for both sequential and simultaneous calibration of exchange flows between segments of a 10-box, 1-dimensional, well mixed, bifurcated tidal mixing model for Tampa Bay. Calibrations were conducted for three model options having different mathematical expressions for evaporative loss. In approaching this project we asked three questions: does simultaneous calibration or sequential calibration yield better box model performance; which evaporation option best predicts observed salinities; and how well does model performance compare to more complex hydrodynamic models. Sequential calibration followed the classical salt balance and steady state approach. The nonlinear parameter estimator (PEST) was used for simultaneous calibration. The sequential approach proved useful in evaluating the three evaporation options. However, simultaneous calibration proved superior in predicting observed salinities but was ineffective in discerning differences between evaporation options. The simultaneously calibrated model produced residence times that fell within the range of more complex hydrodynamic models of Tampa Bay.
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Affiliation(s)
- J E Rogers
- US EPA National Health and Environmental Effects Research Laboratory, Gulf Ecology Division, 1 Sabine Island Drive, Gulf Breeze, FL 32561, USA
| | - M J Russell
- US EPA National Health and Environmental Effects Research Laboratory, Gulf Ecology Division, 1 Sabine Island Drive, Gulf Breeze, FL 32561, USA
| | - M C Harwell
- US EPA National Health and Environmental Effects Research Laboratory, Gulf Ecology Division, 1 Sabine Island Drive, Gulf Breeze, FL 32561, USA
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25
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Barge LM, Branscomb E, Brucato JR, Cardoso SSS, Cartwright JHE, Danielache SO, Galante D, Kee TP, Miguel Y, Mojzsis S, Robinson KJ, Russell MJ, Simoncini E, Sobron P. Thermodynamics, Disequilibrium, Evolution: Far-From-Equilibrium Geological and Chemical Considerations for Origin-Of-Life Research. ORIGINS LIFE EVOL B 2017; 47:39-56. [PMID: 27271006 DOI: 10.1007/s11084-016-9508-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 04/19/2016] [Indexed: 10/21/2022]
Affiliation(s)
- L M Barge
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91125, USA.
- Icy Worlds Team, NASA Astrobiology Institute, Mountain View, CA, 94043, USA.
| | - E Branscomb
- Carl R. Woese Institute for Genomic Biology, University of Illinois, Urbana-Champaign, Champaign, IL, USA
| | - J R Brucato
- Astrophysical Observatory of Arcetri, Florence, Italy
| | - S S S Cardoso
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Pembroke Street, Cambridge, CB2 3RA, UK
| | - J H E Cartwright
- Instituto Andaluz de Ciencias de la Tierra, CSIC-Universidad de Granada, E-18100 Armilla, Granada, Spain
- Instituto Carlos I de Física Teórica y Computacional, Universidad de Granada, E-18071, Granada, Spain
| | - S O Danielache
- Sophia University, Tokyo, Japan
- Earth and Life Science Institute, Tokyo Technical University, Tokyo, Japan
| | - D Galante
- Brazilian Synchrotron Light Laboratory, LNLS / CNPEM, Campinas, Brazil
| | - T P Kee
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Y Miguel
- Observatoire de Côte d'Azur, Nice, France
| | - S Mojzsis
- Department of Geological Sciences, University of Colorado, Boulder, CO, 80309-0399, USA
| | - K J Robinson
- School of Molecular Sciences and School of Earth & Space Exploration, Arizona State University, Tempe, AZ, 85287, USA
| | - M J Russell
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91125, USA
- Icy Worlds Team, NASA Astrobiology Institute, Mountain View, CA, 94043, USA
| | - E Simoncini
- Astrophysical Observatory of Arcetri, Florence, Italy
| | - P Sobron
- Carl Sagan Center, SETI Institute, Mountain View, CA, USA
- Impossible Sensing, St. Louis, MO, USA
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26
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Russell MJ, Goodman TA, Visse JM, Beckett L, Saito N, Lyeth BG, Recanzone GH. Sex and Electrode Configuration in Transcranial Electrical Stimulation. Front Psychiatry 2017; 8:147. [PMID: 28855877 PMCID: PMC5558260 DOI: 10.3389/fpsyt.2017.00147] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 07/28/2017] [Indexed: 02/04/2023] Open
Abstract
Transcranial electrical stimulation (tES) can be an effective non-invasive neuromodulation procedure. Unfortunately, the considerable variation in reported treatment outcomes, both within and between studies, has made the procedure unreliable for many applications. To determine if individual differences in cranium morphology and tissue conductivity can account for some of this variation, the electrical density at two cortical locations (temporal and frontal) directly under scalp electrodes was modeled using a validated MRI modeling procedure in 23 subjects (12 males and 11 females). Three different electrode configurations (non-cephalic, bi-cranial, and ring) commonly used in tES were modeled at three current intensities (0.5, 1.0, and 2.0 mA). The aims were to assess the effects of configuration and current intensity on relative current received at a cortical brain target directly under the stimulating electrode and to characterize individual variation. The different electrode configurations resulted in up to a ninefold difference in mean current densities delivered to the brains. The ring configuration delivered the least current and the non-cephalic the most. Female subjects showed much less current to the brain than male subjects. Individual differences in the current received and differences in electrode configurations may account for significant variability in current delivered and, thus, potentially a significant portion of reported variation in clinical outcomes at two commonly targeted regions of the brain.
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Affiliation(s)
| | | | | | - Laurel Beckett
- Division of Biostatistics, Davis School of Medicine, University of California, Davis, Davis, CA, United States
| | - Naomi Saito
- Division of Biostatistics, Davis School of Medicine, University of California, Davis, Davis, CA, United States
| | - Bruce G Lyeth
- Department of Neurological Surgery, University of California, Davis, Davis, CA, United States
| | - Gregg H Recanzone
- Center for Neuroscience, University of California, Davis, Davis, CA, United States.,Department of Neurobiology, Physiology and Behavior, University of California, Davis, Davis, CA, United States
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Barge LM, Abedian Y, Doloboff IJ, Nuñez JE, Russell MJ, Kidd RD, Kanik I. Chemical Gardens as Flow-through Reactors Simulating Natural Hydrothermal Systems. J Vis Exp 2015:53015. [PMID: 26650915 PMCID: PMC4692733 DOI: 10.3791/53015] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Here we report experimental simulations of hydrothermal chimney growth using injection chemical garden methods. The versatility of this type of experiment allows for testing of various proposed ocean / hydrothermal fluid chemistries that could have driven reactions toward the origin of life in environments on the early Earth, early Mars, or even other worlds such as the icy moons of the outer planets. We show experiments that include growth of chemical garden structures under anoxic conditions simulating the early Earth, inclusion of trace components of phosphates / organics in the injection solution to incorporate them into the structure, a switch of the injection solution to introduce a secondary precipitating anion, and the measurement of membrane potentials generated by chemical gardens. Using this method, self-assembling chemical garden structures were formed that mimic the natural chimneys precipitated at submarine hydrothermal springs, and these precipitates can be used successfully as flow-through reactors by feeding through multiple successive "hydrothermal" injections.
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Affiliation(s)
- Laura M Barge
- NASA Jet Propulsion Laboratory, California Institute of Technology; NASA Astrobiology Institute, Icy Worlds; Blue Marble Space Institute of Science;
| | - Yeghegis Abedian
- NASA Jet Propulsion Laboratory, California Institute of Technology; NASA Astrobiology Institute, Icy Worlds
| | - Ivria J Doloboff
- NASA Jet Propulsion Laboratory, California Institute of Technology; NASA Astrobiology Institute, Icy Worlds
| | - Jessica E Nuñez
- NASA Jet Propulsion Laboratory, California Institute of Technology; Blue Marble Space Institute of Science; Citrus College
| | - Michael J Russell
- NASA Jet Propulsion Laboratory, California Institute of Technology; NASA Astrobiology Institute, Icy Worlds
| | - Richard D Kidd
- NASA Jet Propulsion Laboratory, California Institute of Technology
| | - Isik Kanik
- NASA Jet Propulsion Laboratory, California Institute of Technology; NASA Astrobiology Institute, Icy Worlds
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Barge LM, Cardoso SSS, Cartwright JHE, Cooper GJT, Cronin L, De Wit A, Doloboff IJ, Escribano B, Goldstein RE, Haudin F, Jones DEH, Mackay AL, Maselko J, Pagano JJ, Pantaleone J, Russell MJ, Sainz-Díaz CI, Steinbock O, Stone DA, Tanimoto Y, Thomas NL. From Chemical Gardens to Chemobrionics. Chem Rev 2015; 115:8652-703. [PMID: 26176351 DOI: 10.1021/acs.chemrev.5b00014] [Citation(s) in RCA: 163] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Laura M Barge
- Jet Propulsion Laboratory, California Institute of Technology , Pasadena, California 91109, United States
| | - Silvana S S Cardoso
- Department of Chemical Engineering and Biotechnology, University of Cambridge , Cambridge CB2 3RA, United Kingdom
| | - Julyan H E Cartwright
- Instituto Andaluz de Ciencias de la Tierra, CSIC-Universidad de Granada , E-18100 Armilla, Granada, Spain
| | - Geoffrey J T Cooper
- WestCHEM School of Chemistry, University of Glasgow , Glasgow G12 8QQ, United Kingdom
| | - Leroy Cronin
- WestCHEM School of Chemistry, University of Glasgow , Glasgow G12 8QQ, United Kingdom
| | - Anne De Wit
- Nonlinear Physical Chemistry Unit, CP231, Université libre de Bruxelles (ULB) , B-1050 Brussels, Belgium
| | - Ivria J Doloboff
- Jet Propulsion Laboratory, California Institute of Technology , Pasadena, California 91109, United States
| | - Bruno Escribano
- Basque Center for Applied Mathematics , E-48009 Bilbao, Spain
| | - Raymond E Goldstein
- Department of Applied Mathematics and Theoretical Physics, University of Cambridge , Cambridge CB3 0WA, United Kingdom
| | - Florence Haudin
- Nonlinear Physical Chemistry Unit, CP231, Université libre de Bruxelles (ULB) , B-1050 Brussels, Belgium
| | - David E H Jones
- Department of Chemistry, University of Newcastle upon Tyne , Newcastle upon Tyne NE1 7RU, United Kingdom
| | - Alan L Mackay
- Birkbeck College, University of London , Malet Street, London WC1E 7HX, United Kingdom
| | - Jerzy Maselko
- Department of Chemistry, University of Alaska , Anchorage, Alaska 99508, United States
| | - Jason J Pagano
- Department of Chemistry, Saginaw Valley State University , University Center, Michigan 48710-0001, United States
| | - J Pantaleone
- Department of Physics, University of Alaska , Anchorage, Alaska 99508, United States
| | - Michael J Russell
- Jet Propulsion Laboratory, California Institute of Technology , Pasadena, California 91109, United States
| | - C Ignacio Sainz-Díaz
- Instituto Andaluz de Ciencias de la Tierra, CSIC-Universidad de Granada , E-18100 Armilla, Granada, Spain
| | - Oliver Steinbock
- Department of Chemistry and Biochemistry, Florida State University , Tallahassee, Florida 32306-4390, United States
| | - David A Stone
- Iron Shell LLC , Tucson, Arizona 85717, United States
| | - Yoshifumi Tanimoto
- Faculty of Pharmacy, Osaka Ohtani University , Tondabayashi 548-8540, Japan
| | - Noreen L Thomas
- Department of Materials, Loughborough University , Loughborough LE11 3TU, United Kingdom
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Burcar BT, Barge LM, Trail D, Watson EB, Russell MJ, McGown LB. RNA Oligomerization in Laboratory Analogues of Alkaline Hydrothermal Vent Systems. Astrobiology 2015; 15:509-522. [PMID: 26154881 DOI: 10.1089/ast.2014.1280] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Discovering pathways leading to long-chain RNA formation under feasible prebiotic conditions is an essential step toward demonstrating the viability of the RNA World hypothesis. Intensive research efforts have provided evidence of RNA oligomerization by using circular ribonucleotides, imidazole-activated ribonucleotides with montmorillonite catalyst, and ribonucleotides in the presence of lipids. Additionally, mineral surfaces such as borates, apatite, and calcite have been shown to catalyze the formation of small organic compounds from inorganic precursors (Cleaves, 2008 ), pointing to possible geological sites for the origins of life. Indeed, the catalytic properties of these particular minerals provide compelling evidence for alkaline hydrothermal vents as a potential site for the origins of life since, at these vents, large metal-rich chimney structures can form that have been shown to be energetically favorable to diverse forms of life. Here, we test the ability of iron- and sulfur-rich chimneys to support RNA oligomerization reactions using imidazole-activated and non-activated ribonucleotides. The chimneys were synthesized in the laboratory in aqueous "ocean" solutions under conditions consistent with current understanding of early Earth. Effects of elemental composition, pH, inclusion of catalytic montmorillonite clay, doping of chimneys with small organic compounds, and in situ ribonucleotide activation on RNA polymerization were investigated. These experiments, under certain conditions, showed successful dimerization by using unmodified ribonucleotides, with the generation of RNA oligomers up to 4 units in length when imidazole-activated ribonucleotides were used instead. Elemental analysis of the chimney precipitates and the reaction solutions showed that most of the metal cations that were determined were preferentially partitioned into the chimneys.
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Affiliation(s)
- Bradley T Burcar
- 1 New York Center for Astrobiology, Rensselaer Polytechnic Institute , Troy, New York
- 2 Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute , Troy, New York
| | - Laura M Barge
- 3 NASA Jet Propulsion Laboratory, California Institute of Technology , Pasadena, California
- 4 NASA Astrobiology Institute , Icy Worlds
| | - Dustin Trail
- 1 New York Center for Astrobiology, Rensselaer Polytechnic Institute , Troy, New York
- 5 Department of Earth and Environmental Sciences, Rensselaer Polytechnic Institute School of Science , Troy, New York
| | - E Bruce Watson
- 1 New York Center for Astrobiology, Rensselaer Polytechnic Institute , Troy, New York
- 5 Department of Earth and Environmental Sciences, Rensselaer Polytechnic Institute School of Science , Troy, New York
| | - Michael J Russell
- 3 NASA Jet Propulsion Laboratory, California Institute of Technology , Pasadena, California
- 4 NASA Astrobiology Institute , Icy Worlds
| | - Linda B McGown
- 1 New York Center for Astrobiology, Rensselaer Polytechnic Institute , Troy, New York
- 2 Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute , Troy, New York
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Lewis MA, Russell MJ. Contaminant profiles for surface water, sediment, flora and fauna associated with the mangrove fringe along middle and lower eastern Tampa Bay. Mar Pollut Bull 2015; 95:273-282. [PMID: 25931177 DOI: 10.1016/j.marpolbul.2015.04.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 04/03/2015] [Indexed: 06/04/2023]
Abstract
Contaminant concentrations are reported for surface water, sediment, flora and fauna collected during 2010-2011 from the mangrove fringe along eastern Tampa Bay, Florida. Concentrations of trace metals, chlorinated pesticides, atrazine, total polycyclic aromatic hydrocarbons, and polychlorinated biphenyls were species-, chemical- and location-specific. Contaminants in sediments did not exceed proposed individual sediment quality guidelines. Most sediment quality assessment quotients were less than one indicating the likelihood of no inhibitory effect based on chemical measurements alone. Faunal species typically contained more contaminants than plant species; seagrass usually contained more chemicals than mangroves. Bioconcentration factors for marine angiosperms were usually less than 10 and ranged between 1 and 31. Mercury concentrations (ppm) in blue crabs and fish did not exceed the U.S. Environmental Protection Agency fish tissue criterion of 0.3 and the U.S. Food and Drug Administration action level of 1.0. In contrast, total mercury concentrations in faunal species often exceeded guideline values for wildlife consumers of aquatic biota.
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Affiliation(s)
- M A Lewis
- U.S. Environmental Protection Agency, Gulf Ecology Division, Gulf Breeze, FL 32561, USA.
| | - M J Russell
- U.S. Environmental Protection Agency, Gulf Ecology Division, Gulf Breeze, FL 32561, USA.
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Barge LM, Abedian Y, Russell MJ, Doloboff IJ, Cartwright JHE, Kidd RD, Kanik I. From Chemical Gardens to Fuel Cells: Generation of Electrical Potential and Current Across Self-Assembling Iron Mineral Membranes. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201501663] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Barge LM, Abedian Y, Russell MJ, Doloboff IJ, Cartwright JHE, Kidd RD, Kanik I. From Chemical Gardens to Fuel Cells: Generation of Electrical Potential and Current Across Self-Assembling Iron Mineral Membranes. Angew Chem Int Ed Engl 2015; 54:8184-7. [DOI: 10.1002/anie.201501663] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Indexed: 12/12/2022]
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Ducluzeau AL, Schoepp-Cothenet B, van Lis R, Baymann F, Russell MJ, Nitschke W. The evolution of respiratory O2/NO reductases: an out-of-the-phylogenetic-box perspective. J R Soc Interface 2015; 11:20140196. [PMID: 24968694 DOI: 10.1098/rsif.2014.0196] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Complex life on our planet crucially depends on strong redox disequilibria afforded by the almost ubiquitous presence of highly oxidizing molecular oxygen. However, the history of O2-levels in the atmosphere is complex and prior to the Great Oxidation Event some 2.3 billion years ago, the amount of O2 in the biosphere is considered to have been extremely low as compared with present-day values. Therefore the evolutionary histories of life and of O2-levels are likely intricately intertwined. The obvious biological proxy for inferring the impact of changing O2-levels on life is the evolutionary history of the enzyme allowing organisms to tap into the redox power of molecular oxygen, i.e. the bioenergetic O2 reductases, alias the cytochrome and quinol oxidases. Consequently, molecular phylogenies reconstructed for this enzyme superfamily have been exploited over the last two decades in attempts to elucidate the interlocking between O2 levels in the environment and the evolution of respiratory bioenergetic processes. Although based on strictly identical datasets, these phylogenetic approaches have led to diametrically opposite scenarios with respect to the history of both the enzyme superfamily and molecular oxygen on the Earth. In an effort to overcome the deadlock of molecular phylogeny, we here review presently available structural, functional, palaeogeochemical and thermodynamic information pertinent to the evolution of the superfamily (which notably also encompasses the subfamily of nitric oxide reductases). The scenario which, in our eyes, most closely fits the ensemble of these non-phylogenetic data, sees the low O2-affinity SoxM- (or A-) type enzymes as the most recent evolutionary innovation and the high-affinity O2 reductases (SoxB or B and cbb3 or C) as arising independently from NO-reducing precursor enzymes.
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Affiliation(s)
- Anne-Lise Ducluzeau
- Beadle Center, University of Nebraska-Lincoln, 1901 Vine Street, Lincoln, NE 68588-0660, USA
| | - Barbara Schoepp-Cothenet
- Laboratoire de Bioénergétique et Ingénierie des Protéines UMR 7281 CNRS/AMU, FR3479, Marseille Cedex 20 13402, France
| | - Robert van Lis
- Laboratoire de Bioénergétique et Ingénierie des Protéines UMR 7281 CNRS/AMU, FR3479, Marseille Cedex 20 13402, France
| | - Frauke Baymann
- Laboratoire de Bioénergétique et Ingénierie des Protéines UMR 7281 CNRS/AMU, FR3479, Marseille Cedex 20 13402, France
| | - Michael J Russell
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099, USA
| | - Wolfgang Nitschke
- Laboratoire de Bioénergétique et Ingénierie des Protéines UMR 7281 CNRS/AMU, FR3479, Marseille Cedex 20 13402, France
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Russell MJ, Barge LM, Bhartia R, Bocanegra D, Bracher PJ, Branscomb E, Kidd R, McGlynn S, Meier DH, Nitschke W, Shibuya T, Vance S, White L, Kanik I. The drive to life on wet and icy worlds. Astrobiology 2014; 14:308-43. [PMID: 24697642 PMCID: PMC3995032 DOI: 10.1089/ast.2013.1110] [Citation(s) in RCA: 123] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 02/02/2014] [Indexed: 05/22/2023]
Abstract
This paper presents a reformulation of the submarine alkaline hydrothermal theory for the emergence of life in response to recent experimental findings. The theory views life, like other self-organizing systems in the Universe, as an inevitable outcome of particular disequilibria. In this case, the disequilibria were two: (1) in redox potential, between hydrogen plus methane with the circuit-completing electron acceptors such as nitrite, nitrate, ferric iron, and carbon dioxide, and (2) in pH gradient between an acidulous external ocean and an alkaline hydrothermal fluid. Both CO2 and CH4 were equally the ultimate sources of organic carbon, and the metal sulfides and oxyhydroxides acted as protoenzymatic catalysts. The realization, now 50 years old, that membrane-spanning gradients, rather than organic intermediates, play a vital role in life's operations calls into question the idea of "prebiotic chemistry." It informs our own suggestion that experimentation should look to the kind of nanoengines that must have been the precursors to molecular motors-such as pyrophosphate synthetase and the like driven by these gradients-that make life work. It is these putative free energy or disequilibria converters, presumably constructed from minerals comprising the earliest inorganic membranes, that, as obstacles to vectorial ionic flows, present themselves as the candidates for future experiments. Key Words: Methanotrophy-Origin of life. Astrobiology 14, 308-343. The fixation of inorganic carbon into organic material (autotrophy) is a prerequisite for life and sets the starting point of biological evolution. (Fuchs, 2011 ) Further significant progress with the tightly membrane-bound H(+)-PPase family should lead to an increased insight into basic requirements for the biological transport of protons through membranes and its coupling to phosphorylation. (Baltscheffsky et al., 1999 ).
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Ducluzeau AL, Schoepp-Cothenet B, Baymann F, Russell MJ, Nitschke W. Free energy conversion in the LUCA: Quo vadis? Biochim Biophys Acta 2013; 1837:982-8. [PMID: 24361840 DOI: 10.1016/j.bbabio.2013.12.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 12/08/2013] [Accepted: 12/12/2013] [Indexed: 11/30/2022]
Abstract
Living entities are unimaginable without means to harvest free energy from the environment, that is, without bioenergetics. The quest to understand the bioenergetic ways of early life therefore is one of the crucial elements to understand the emergence of life on our planet. Over the last few years, several mutually exclusive scenarios for primordial bioenergetics have been put forward, all of which are based on some sort of empirical observation, a remarkable step forward from the previous, essentially untestable, ab initio models. We here try to present and compare these scenarios while at the same time discuss their respective empirical weaknesses. The goal of this article is to harness crucial new expertise from the entire field by stimulating a larger part of the bioenergetics community to become involved in "origin-of-energy-metabolism" research. This article is part of a Special Issue entitled: 18th European Bioenergetic Conference.
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Affiliation(s)
- Anne-Lise Ducluzeau
- Beadle Center, University of Nebraska-Lincoln, 1901 Vine Street, Lincoln, NE 68588-0660, USA
| | - Barbara Schoepp-Cothenet
- Laboratoire de Bioénergétique et Ingénierie des Protéines UMR 7281 CNRS/AMU, FR3479, F-13402 Marseille Cedex 20, France
| | - Frauke Baymann
- Laboratoire de Bioénergétique et Ingénierie des Protéines UMR 7281 CNRS/AMU, FR3479, F-13402 Marseille Cedex 20, France
| | - Michael J Russell
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099, USA
| | - Wolfgang Nitschke
- Laboratoire de Bioénergétique et Ingénierie des Protéines UMR 7281 CNRS/AMU, FR3479, F-13402 Marseille Cedex 20, France.
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Russell MJ, Goodman T, Pierson R, Shepherd S, Wang Q, Groshong B, Wiley DF. Individual differences in transcranial electrical stimulation current density. J Biomed Res 2013; 27:495-508. [PMID: 24285948 PMCID: PMC3841475 DOI: 10.7555/jbr.27.20130074] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Revised: 07/16/2013] [Accepted: 07/28/2013] [Indexed: 12/23/2022] Open
Abstract
Transcranial electrical stimulation (TCES) is effective in treating many conditions, but it has not been possible to accurately forecast current density within the complex anatomy of a given subject's head. We sought to predict and verify TCES current densities and determine the variability of these current distributions in patient-specific models based on magnetic resonance imaging (MRI) data. Two experiments were performed. The first experiment estimated conductivity from MRIs and compared the current density results against actual measurements from the scalp surface of 3 subjects. In the second experiment, virtual electrodes were placed on the scalps of 18 subjects to model simulated current densities with 2 mA of virtually applied stimulation. This procedure was repeated for 4 electrode locations. Current densities were then calculated for 75 brain regions. Comparison of modeled and measured external current in experiment 1 yielded a correlation of r = .93. In experiment 2, modeled individual differences were greatest near the electrodes (ten-fold differences were common), but simulated current was found in all regions of the brain. Sites that were distant from the electrodes (e.g. hypothalamus) typically showed two-fold individual differences. MRI-based modeling can effectively predict current densities in individual brains. Significant variation occurs between subjects with the same applied electrode configuration. Individualized MRI-based modeling should be considered in place of the 10-20 system when accurate TCES is needed.
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Abstract
Life is evolutionarily the most complex of the emergent symmetry-breaking, macroscopically organized dynamic structures in the Universe. Members of this cascading series of disequilibria-converting systems, or engines in Cottrell's terminology, become ever more complicated-more chemical and less physical-as each engine extracts, exploits and generates ever lower grades of energy and resources in the service of entropy generation. Each one of these engines emerges spontaneously from order created by a particular mother engine or engines, as the disequilibrated potential daughter is driven beyond a critical point. Exothermic serpentinization of ocean crust is life's mother engine. It drives alkaline hydrothermal convection and thereby the spontaneous production of precipitated submarine hydrothermal mounds. Here, the two chemical disequilibria directly causative in the emergence of life spontaneously arose across the mineral precipitate membranes separating the acidulous, nitrate-bearing CO2-rich, Hadean sea from the alkaline and CH4/H2-rich serpentinization-generated effluents. Essential redox gradients-involving hydrothermal CH4 and H2 as electron donors, CO2 and nitrate, nitrite, and ferric iron from the ambient ocean as acceptors-were imposed which functioned as the original 'carbon-fixing engine'. At the same time, a post-critical-point (milli)voltage pH potential (proton concentration gradient) drove the condensation of orthophosphate to produce a high energy currency: 'the pyrophosphatase engine'.
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Affiliation(s)
- Michael J Russell
- Planetary Science Section 3225, MS:183-301, Jet Propulsion Laboratory, California Institute of Technology, , 4800 Oak Grove Drive, Pasadena, CA 91109-8099, USA.
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Abstract
Attempts to draft plausible scenarios for the origin of life have in the past mainly built upon palaeogeochemical boundary conditions while, as detailed in a companion article in this issue, frequently neglecting to comply with fundamental thermodynamic laws. Even if demands from both palaeogeochemistry and thermodynamics are respected, then a plethora of strongly differing models are still conceivable. Although we have no guarantee that life at its origin necessarily resembled biology in extant organisms, we consider that the only empirical way to deduce how life may have emerged is by taking the stance of assuming continuity of biology from its inception to the present day. Building upon this conviction, we have assessed extant types of energy and carbon metabolism for their appropriateness to conditions probably pertaining in those settings of the Hadean planet that fulfil the thermodynamic requirements for life to come into being. Wood-Ljungdahl (WL) pathways leading to acetyl CoA formation are excellent candidates for such primordial metabolism. Based on a review of our present understanding of the biochemistry and biophysics of acetogenic, methanogenic and methanotrophic pathways and on a phylogenetic analysis of involved enzymes, we propose that a variant of modern methanotrophy is more likely than traditional WL systems to date back to the origin of life. The proposed model furthermore better fits basic thermodynamic demands and palaeogeochemical conditions suggested by recent results from extant alkaline hydrothermal seeps.
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Affiliation(s)
- Wolfgang Nitschke
- Bioénergétique et Ingénierie des Protéines UMR7281, CNRS/AMU, FR3479 Marseille, France.
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Nitschke W, McGlynn SE, Milner-White EJ, Russell MJ. On the antiquity of metalloenzymes and their substrates in bioenergetics. Biochim Biophys Acta 2013; 1827:871-81. [PMID: 23454059 DOI: 10.1016/j.bbabio.2013.02.008] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 02/15/2013] [Accepted: 02/18/2013] [Indexed: 02/07/2023]
Abstract
Many metalloenzymes that inject and extract reducing equivalents at the beginning and the end of electron transport chains involved in chemiosmosis are suggested, through phylogenetic analysis, to have been present in the Last Universal Common Ancestor (LUCA). Their active centres are affine with the structures of minerals presumed to contribute to precipitate membranes produced on the mixing of hydrothermal solutions with the Hadean Ocean ~4 billion years ago. These mineral precipitates consist of transition element sulphides and oxides such as nickelian mackinawite ([Fe>Ni]2S2), a nickel-bearing greigite (~FeSS[Fe3NiS4]SSFe), violarite (~NiSS[Fe2Ni2S4]SSNi), a molybdenum bearing complex (~Mo(IV/VI)2Fe3S(0/2-)9) and green rust or fougerite (~[Fe(II)Fe(III)(OH)4](+)[OH](-)). They may be respectively compared with the active centres of Ni-Fe hydrogenase, carbon monoxide dehydrogenase (CODH), acetyl coenzyme-A synthase (ACS), the complex iron-sulphur molybdoenzyme (CISM) superfamily and methane monooxygenase (MMO). With the look of good catalysts - a suggestion that gathers some support from prebiotic hydrothermal experimentation - and sequestered by short peptides, they could be thought of as the original building blocks of proto-enzyme active centres. This convergence of the makeup of the LUCA-metalloenzymes with mineral structure and composition of hydrothermal precipitates adds credence to the alkaline hydrothermal (chemiosmotic) theory for the emergence of life, specifically to the possibility that the first metabolic pathway - the acetyl CoA pathway - was initially driven from either end, reductively from CO2 to CO and oxidatively and reductively from CH4 through to a methane thiol group, the two entities assembled with the help of a further thiol on a violarite cluster sequestered by peptides. By contrast, the organic coenzymes were entirely a product of the first metabolic pathways. This article is part of a Special Issue entitled: Metals in Bioenergetics and Biomimetics Systems.
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Affiliation(s)
- Wolfgang Nitschke
- Laboratoire de Bioénergétique et Ingénierie des Protéines, Marseille Cedex 20, France
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Branscomb E, Russell MJ. Turnstiles and bifurcators: the disequilibrium converting engines that put metabolism on the road. Biochim Biophys Acta 2012; 1827:62-78. [PMID: 23063910 DOI: 10.1016/j.bbabio.2012.10.003] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Revised: 10/02/2012] [Accepted: 10/03/2012] [Indexed: 10/27/2022]
Abstract
The Submarine Hydrothermal Alkaline Spring Theory for the emergence of life holds that it is the ordered delivery of hydrogen and methane in alkaline hydrothermal solutions at a spontaneously precipitated inorganic osmotic and catalytic membrane to the carbon dioxide and other electron acceptors in the earliest acidulous cool ocean that, through these gradients, drove life into being. That such interactions between hydrothermal fuels and potential oxidants have so far not been accomplished in the lab is because some steps along the necessary metabolic pathways are endergonic and must therefore be driven by being coupled to thermodynamically larger exergonic processes. But coupling of this kind is far from automatic and it is not enough to merely sum the ΔGs of two supposedly coupled reactions and show their combined thermodynamic viability. An exergonic reaction will not drive an endergonic one unless 'forced' to do so by being tied to it mechanistically via an organized "engine" of "Free Energy Conversion" (FEC). Here we discuss the thermodynamics of FEC and advance proposals regarding the nature and roles of the FEC devices that could, in principle, have arisen spontaneously in the alkaline hydrothermal context and have forced the onset of a protometabolism. The key challenge is to divine what these initial engines of life were in physicochemical terms and as part of that, what structures provided the first "turnstile-like" mechanisms needed to couple the partner processes in free energy conversion; in particular to couple the dissipation of geochemically given gradients to, say, the reduction of CO(2) to formate and the generation of a pyrophosphate disequilibrium. This article is part of a Special Issue entitled: The evolutionary aspects of bioenergetic systems.
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Schoepp-Cothenet B, van Lis R, Atteia A, Baymann F, Capowiez L, Ducluzeau AL, Duval S, ten Brink F, Russell MJ, Nitschke W. On the universal core of bioenergetics. Biochim Biophys Acta 2012; 1827:79-93. [PMID: 22982447 DOI: 10.1016/j.bbabio.2012.09.005] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 09/06/2012] [Accepted: 09/07/2012] [Indexed: 01/05/2023]
Abstract
Living cells are able to harvest energy by coupling exergonic electron transfer between reducing and oxidising substrates to the generation of chemiosmotic potential. Whereas a wide variety of redox substrates is exploited by prokaryotes resulting in very diverse layouts of electron transfer chains, the ensemble of molecular architectures of enzymes and redox cofactors employed to construct these systems is stunningly small and uniform. An overview of prominent types of electron transfer chains and of their characteristic electrochemical parameters is presented. We propose that basic thermodynamic considerations are able to rationalise the global molecular make-up and functioning of these chemiosmotic systems. Arguments from palaeogeochemistry and molecular phylogeny are employed to discuss the evolutionary history leading from putative energy metabolisms in early life to the chemiosmotic diversity of extant organisms. Following the Occam's razor principle, we only considered for this purpose origin of life scenarios which are contiguous with extant life. This article is part of a Special Issue entitled: The evolutionary aspects of bioenergetic systems.
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Affiliation(s)
- Barbara Schoepp-Cothenet
- Laboratoire de Bioénergétique et Ingénierie des Protéines UMR 7281 CNRS/AMU, FR3479, F-13402 Marseille Cedex 20, France.
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McGlynn SE, Kanik I, Russell MJ. Peptide and RNA contributions to iron-sulphur chemical gardens as life's first inorganic compartments, catalysts, capacitors and condensers. Philos Trans A Math Phys Eng Sci 2012; 370:3007-3022. [PMID: 22615473 DOI: 10.1098/rsta.2011.0211] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Hydrothermal chimneys and compartments comprising transition metal sulphides and associated minerals have been proposed as likely locations for the beginnings of life. In laboratory simulations of off-axis alkaline springs, it is shown that the interaction of a simulated alkaline sulphide-bearing submarine vent solution with a primeval anoxic iron-bearing ocean leads to the formation of chimney structures reminiscent of chemical gardens. These chimneys display periodicity in their deposition and exhibit diverse morphologies and mineralogies, affording the possibilities of catalysis and molecular sequestration. The addition of peptides and RNA to the alkaline solution modifies the elemental stoichiometry of the chimneys-perhaps indicating the very initial stage of the organic takeover on the way to living cells by charged organic polymers potentially synthesized in this same environment.
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Affiliation(s)
- Shawn E McGlynn
- Planetary Science Section 3220, MS:183-301, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099, USA
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Barge LM, Doloboff IJ, White LM, Stucky GD, Russell MJ, Kanik I. Characterization of iron-phosphate-silicate chemical garden structures. Langmuir 2012; 28:3714-3721. [PMID: 22035594 DOI: 10.1021/la203727g] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Chemical gardens form when ferrous chloride hydrate seed crystals are added or concentrated solutions are injected into solutions of sodium silicate and potassium phosphate. Various precipitation morphologies are observed depending on silicate and phosphate concentrations, including hollow plumes, bulbs, and tubes. The growth of precipitates is controlled by the internal osmotic pressure, fluid buoyancy, and membrane strength. Additionally, rapid bubble-led growth is observed when silicate concentrations are high. ESEM/EDX analysis confirms compositional gradients within the membranes, and voltage measurements across the membranes during growth show a final potential of around 150-200 mV, indicating that electrochemical gradients are maintained across the membranes as growth proceeds. The characterization of chemical gardens formed with iron, silicate, and phosphate, three important components of an early earth prebiotic hydrothermal system, can help us understand the properties of analogous structures that likely formed at submarine alkaline hydrothermal vents in the Hadean-structures offering themselves as the hatchery of life.
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Affiliation(s)
- Laura M Barge
- Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, California 91109, USA.
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Schoepp-Cothenet B, van Lis R, Philippot P, Magalon A, Russell MJ, Nitschke W. The ineluctable requirement for the trans-iron elements molybdenum and/or tungsten in the origin of life. Sci Rep 2012; 2:263. [PMID: 22355775 PMCID: PMC3278043 DOI: 10.1038/srep00263] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Accepted: 01/09/2012] [Indexed: 11/26/2022] Open
Abstract
An evolutionary tree of key enzymes from the Complex-Iron-Sulfur-Molybdoenzyme (CISM) superfamily distinguishes "ancient" members, i.e. enzymes present already in the last universal common ancestor (LUCA) of prokaryotes, from more recently evolved subfamilies. The majority of the presented subfamilies and, as a consequence, the Molybdo-enzyme superfamily as a whole, appear to have existed in LUCA. The results are discussed with respect to the nature of bioenergetic substrates available to early life and to problems arising from the low solubility of molybdenum under conditions of the primordial Earth.
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Affiliation(s)
- Barbara Schoepp-Cothenet
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP), CNRS, Univ. Aix/Marseille, Marseille/France
| | - Robert van Lis
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP), CNRS, Univ. Aix/Marseille, Marseille/France
| | | | - Axel Magalon
- Laboratoire de Chimie Bactérienne (LCB), CNRS, Univ. Aix/Marseille, Marseille/France
| | - Michael J. Russell
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California
| | - Wolfgang Nitschke
- Laboratoire de Bioénergétique et Ingénierie des Protéines (BIP), CNRS, Univ. Aix/Marseille, Marseille/France
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Mielke RE, Robinson KJ, White LM, McGlynn SE, McEachern K, Bhartia R, Kanik I, Russell MJ. Iron-sulfide-bearing chimneys as potential catalytic energy traps at life's emergence. Astrobiology 2011; 11:933-950. [PMID: 22111762 DOI: 10.1089/ast.2011.0667] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The concept that life emerged where alkaline hydrogen-bearing submarine hot springs exhaled into the most ancient acidulous ocean was used as a working hypothesis to investigate the nature of precipitate membranes. Alkaline solutions at 25-70°C and pH between 8 and 12, bearing HS(-)±silicate, were injected slowly into visi-jars containing ferrous chloride to partially simulate the early ocean on this or any other wet and icy, geologically active rocky world. Dependent on pH and sulfide content, fine tubular chimneys and geodal bubbles were generated with semipermeable walls 4-100 μm thick that comprised radial platelets of nanometric mackinawite [FeS]±ferrous hydroxide [∼Fe(OH)(2)], accompanied by silica and, at the higher temperature, greigite [Fe(3)S(4)]. Within the chimney walls, these platelets define a myriad of micropores. The interior walls of the chimneys host iron sulfide framboids, while, in cases where the alkaline solution has a pH>11 or relatively low sulfide content, their exteriors exhibit radial flanges with a spacing of ∼4 μm that comprise microdendrites of ferrous hydroxide. We speculate that this pattern results from outward and inward radial flow through the chimney walls. The outer Fe(OH)(2) flanges perhaps precipitate where the highly alkaline flow meets the ambient ferrous iron-bearing fluid, while the intervening troughs signal where the acidulous iron-bearing solutions could gain access to the sulfidic and alkaline interior of the chimneys, thereby leading to the precipitation of the framboids. Addition of soluble pentameric peptides enhances membrane durability and accentuates the crenulations on the chimney exteriors. These dynamic patterns may have implications for acid-base catalysis and the natural proton motive force acting through the matrix of the porous inorganic membrane. Thus, within such membranes, steep redox and pH gradients would bear across the nanometric platelets and separate the two counter-flowing solutions, a condition that may have led to the onset of an autotrophic metabolism through the reduction of carbon dioxide.
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Affiliation(s)
- Randall E Mielke
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
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Simoncini E, Russell MJ, Kleidon A. Modeling free energy availability from Hadean hydrothermal systems to the first metabolism. ORIGINS LIFE EVOL B 2011; 41:529-32. [PMID: 22139512 DOI: 10.1007/s11084-011-9251-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Accepted: 07/24/2011] [Indexed: 11/30/2022]
Abstract
Off-axis Hydrothermal Systems (HSs) are seen as the possible setting for the emergence of life. As the availability of free energy is a general requirement to drive any form of metabolism, we ask here under which conditions free energy generation by geologic processes is greatest and relate these to the conditions found at off-axis HSs. To do so, we present a conceptual model in which we explicitly capture the energetics of fluid motion and its interaction with exothermic reactions to maintain a state of chemical disequilibrium. Central to the interaction is the temperature at which the exothermic reactions take place. This temperature not only sets the equilibrium constant of the chemical reactions and thereby the distance of the actual state to chemical equilibrium, but these reactions also shape the temperature gradient that drives convection and thereby the advection of reactants to the reaction sites and the removal of the products that relate to geochemical free energy generation. What this conceptual model shows is that the positive feedback between convection and the chemical kinetics that is found at HSs favors a greater rate of free energy generation than in the absence of convection. Because of the lower temperatures and because the temperature of reactions is determined more strongly by these dynamics rather than an external heat flux, the conditions found at off-axis HSs should result in the greatest rates of geochemical free energy generation. Hence, we hypothesize from these thermodynamic considerations that off-axis HSs seem most conducive for the emergence of protometabolic pathways as these provide the greatest, abiotic generation rates of chemical free energy.
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Affiliation(s)
- E Simoncini
- Max Planck Institut für Biogeochemie, Hans-Knöll-Strasse 10, Jena, 07745, Germany.
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Rosman IS, Lind AC, Russell MJ, Heffernan MP. Pruritic scaly rash on arms and legs. ACTA ACUST UNITED AC 2011; 147:1317-22. [PMID: 22106122 DOI: 10.1001/archdermatol.2011.325-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Nitschke W, Russell MJ. Redox bifurcations: mechanisms and importance to life now, and at its origin: a widespread means of energy conversion in biology unfolds…. Bioessays 2011; 34:106-9. [PMID: 22045626 DOI: 10.1002/bies.201100134] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Wolfgang Nitschke
- Bioénergétique et Ingénierie des Protéines (UPR9036), CNRS/IFR88, Marseille, France.
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Milner-White EJ, Russell MJ. Functional capabilities of the earliest peptides and the emergence of life. Genes (Basel) 2011; 2:671-88. [PMID: 24710286 PMCID: PMC3927598 DOI: 10.3390/genes2040671] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2011] [Revised: 09/14/2011] [Accepted: 09/14/2011] [Indexed: 02/01/2023] Open
Abstract
Considering how biological macromolecules first evolved, probably within a marine environment, it seems likely the very earliest peptides were not encoded by nucleic acids, or at least not via the genetic code as we know it. An objective of the present work is to demonstrate that sequence-independent peptides, or peptides with variable and unreliable lengths and sequences, have the potential to perform a variety of chemically useful functions such as anion and cation binding and membrane and channel formation as well as simple types of catalysis. These functions tend to be performed with the assistance of the main chain CONH atoms rather than the more variable or limited side chain atoms of the peptides presumed to exist then.
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Affiliation(s)
- E James Milner-White
- College of Medical, Veterinary and Life Sciences, Glasgow University, Glasgow G128QQ, UK.
| | - Michael J Russell
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
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Schoepp-Cothenet B, Nitschke W, Barge LM, Ponce A, Russell MJ, Tsapin AI. Comment on "A bacterium that can grow by using arsenic instead of phosphorus". Science 2011; 332:1149; author reply 1149. [PMID: 21622707 DOI: 10.1126/science.1201438] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Wolfe-Simon et al. (Research Articles, 3 June 2011, p. 1163; published online 2 December 2010) argued that the bacterial strain GFAJ-1 can vary the elemental composition of its biomolecules by substituting arsenic for phosphorus. Although their data show that GFAJ-1 is an extraordinary extremophile, consideration of arsenate redox chemistry undermines the suggestion that arsenate can replace the physiologic functions of phosphate.
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Affiliation(s)
- B Schoepp-Cothenet
- Bioénergétique et Ingénierie des Protéines, IFR88, CNRS, 13402 Marseille, France
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