Advanced Panspermia
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Building Blocks That Fall from the Sky
Building blocks that fall from the sky How did life on Earth begin? Scientists from the “Heidelberg Initiative for the Origin of Life” have set about answering this truly existential question. Indeed, they are going one step further and examining the conditions under which life can emerge. The initiative was founded by Thomas Henning, Director at the Max Planck Institute for Astronomy in Heidelberg, and brings together researchers from chemistry, physics and the geological and biological sciences. 18 MaxPlanckResearch 3 | 18 FOCUS_The Origin of Life TEXT THOMAS BUEHRKE he great questions of our exis- However, recent developments are The initiative was triggered by the dis- tence are the ones that fasci- forcing researchers to break down this covery of an ever greater number of nate us the most: how did the specialization and combine different rocky planets orbiting around stars oth- universe evolve, and how did disciplines. “That’s what we’re trying er than the Sun. “We now know that Earth form and life begin? to do with the Heidelberg Initiative terrestrial planets of this kind are more DoesT life exist anywhere else, or are we for the Origins of Life, which was commonplace than the Jupiter-like gas alone in the vastness of space? By ap- founded three years ago,” says Thom- giants we identified initially,” says Hen- proaching these puzzles from various as Henning. HIFOL, as the initiative’s ning. Accordingly, our Milky Way alone angles, scientists can answer different as- name is abbreviated, not only incor- is home to billions of rocky planets, pects of this question. -
Modelling Panspermia in the TRAPPIST-1 System
October 13, 2017 Modelling panspermia in the TRAPPIST-1 system James A. Blake1,2*, David J. Armstrong1,2, Dimitri Veras1,2 Abstract The recent ground-breaking discovery of seven temperate planets within the TRAPPIST-1 system has been hailed as a milestone in the development of exoplanetary science. Centred on an ultra-cool dwarf star, the planets all orbit within a sixth of the distance from Mercury to the Sun. This remarkably compact nature makes the system an ideal testbed for the modelling of rapid lithopanspermia, the idea that micro-organisms can be distributed throughout the Universe via fragments of rock ejected during a meteoric impact event. We perform N-body simulations to investigate the timescale and success-rate of lithopanspermia within TRAPPIST-1. In each simulation, test particles are ejected from one of the three planets thought to lie within the so-called ‘habitable zone’ of the star into a range of allowed orbits, constrained by the ejection velocity and coplanarity of the case in question. The irradiance received by the test particles is tracked throughout the simulation, allowing the overall radiant exposure to be calculated for each one at the close of its journey. A simultaneous in-depth review of space microbiological literature has enabled inferences to be made regarding the potential survivability of lithopanspermia in compact exoplanetary systems. 1Department of Physics, University of Warwick, Coventry, CV4 7AL 2Centre for Exoplanets and Habitability, University of Warwick, Coventry, CV4 7AL *Corresponding author: [email protected] Contents Universe, and can propagate from one location to another. This interpretation owes itself predominantly to the works of William 1 Introduction1 Thompson (Lord Kelvin) and Hermann von Helmholtz in the 1.1 Mechanisms for panspermia...............2 latter half of the 19th Century. -
Prebiological Evolution and the Metabolic Origins of Life
Prebiological Evolution and the Andrew J. Pratt* Metabolic Origins of Life University of Canterbury Keywords Abiogenesis, origin of life, metabolism, hydrothermal, iron Abstract The chemoton model of cells posits three subsystems: metabolism, compartmentalization, and information. A specific model for the prebiological evolution of a reproducing system with rudimentary versions of these three interdependent subsystems is presented. This is based on the initial emergence and reproduction of autocatalytic networks in hydrothermal microcompartments containing iron sulfide. The driving force for life was catalysis of the dissipation of the intrinsic redox gradient of the planet. The codependence of life on iron and phosphate provides chemical constraints on the ordering of prebiological evolution. The initial protometabolism was based on positive feedback loops associated with in situ carbon fixation in which the initial protometabolites modified the catalytic capacity and mobility of metal-based catalysts, especially iron-sulfur centers. A number of selection mechanisms, including catalytic efficiency and specificity, hydrolytic stability, and selective solubilization, are proposed as key determinants for autocatalytic reproduction exploited in protometabolic evolution. This evolutionary process led from autocatalytic networks within preexisting compartments to discrete, reproducing, mobile vesicular protocells with the capacity to use soluble sugar phosphates and hence the opportunity to develop nucleic acids. Fidelity of information transfer in the reproduction of these increasingly complex autocatalytic networks is a key selection pressure in prebiological evolution that eventually leads to the selection of nucleic acids as a digital information subsystem and hence the emergence of fully functional chemotons capable of Darwinian evolution. 1 Introduction: Chemoton Subsystems and Evolutionary Pathways Living cells are autocatalytic entities that harness redox energy via the selective catalysis of biochemical transformations. -
Regarding Belief in Primordial Soup to Explain the Origin of Life
Regarding Belief in Primordial Soup to explain the Origin of Life Belief in a primordial soup where life might spontaneously evolve is as wrong as believing the earth is flat, or, as Hoyle and Wickramasinghe (1981) suggest, as wrong as believing that the pre-Copernican idea that the earth is the center of the universe. They state, “It will be no bad thing to abandon this position” (p. 138). The belief in primordial soup goes something like this: “Somehow a brew of appropriate chemicals managed to get together, the organic soup, and somehow the chemicals managed to shuffle themselves into an early primitive life-form. From then on, all appeared to be plain-sailing, natural selection operating on randomly generated mutations would do the rest” (p. 131). Today we know that life does not arise spontaneously. In the 1860s, Louis Pasteur demonstrated that “the concept of spontaneous generation” was incorrect using “carefully designed experiments” (p. 36). Yet many biologists still “believe that life started on Earth through spontaneous processes” (p. 37). “The recourse to an organic soup to cross this biggest hurdle is evidently a blatant recourse to the spontaneous generation theory which Pasteur claimed to have destroyed. Nevertheless, most scientists, even to this day, have been satisfied to accept it” (p. 37). What scientific tests did Louis Pasteur conduct about spontaneous generation of life? How did he set up his experiment? What were his steps? What was his result? _________________________________________________________________ _________________________________________________________________ -
6 Dynamical Generalizations of the Drake Equation: the Linear and Non-Linear Theories
6 Dynamical Generalizations of the Drake Equation: The Linear and Non-linear Theories Alexander D. Panov Abstract The Drake equation pertains to the essentially equilibrium situation in a popu- lation of communicative civilizations of the Galaxy, but it does not describe dynamical processes which can occur in it. Both linear and non-linear dynam- ical population analyses are built out and discussed instead of the Drake equa- tion. Keywords: SETI, the Drake equation, linear population analysis, non-linear population analysis. Introduction Communicative civilizations (CCs) are the ones which tend to send messages to other civilizations and are able to receive and analyze messages from other civili- zations. The crucial question of the SETI problem is how far the nearest CC from us is. Its answer depends on the number of CCs existing in the Galaxy at present. Fig. 1 shows how the distance between the Sun and the nearest CC depends on the number of CCs in the Galaxy. The calculation was made by us by the Monte Carlo method with the use of a realistic model of the distribution of stars in the Galaxy (Allen 1973) and the actual location of the Sun in the Galaxy (8.5 kpc from the center of the Galaxy). The best known way to answer the question about the number of CCs is the formula by F. Drake N R f n f f f L C * p e l i c , (Eq. 1) where R∗ is a star-formation rate in the Galaxy averaged with respect to all time of its existence, fp is the part of stars with planet systems, nе is the average number of planets in systems suitable for life, fl is the part of planet on which life did appear, fi is the part of planets on which intelligent forms of life devel- oped, fc is the part of planets on which life reached the communicative phase, L is the average duration of the communicative phase. -
The Place of RNA in the Origin and Early Evolution of the Genetic Machinery
ISSN 2075-1729 www.mdpi.com/journal/life Peer-Review Record: The Place of RNA in the Origin and Early Evolution of the Genetic Machinery Günter Wächtershäuser Life 2014, 4, 1050-1091, doi:10.3390/4041050 Reviewer 1: Anonymous Reviewer 2: Wolfgang Buckel Editor: Niles Lehman (Guest editor of Special Issue “The Origins and Early Evolution of RNA”) Received: 24 October 2014 First Revision Received: 2 December 2014 Accepted: 9 December 2014 Published: 19 December 2014 First Round of Evaluation Round 1: Reviewer 1 Report and Author Response In this massive and dense manuscript, Günter Wächtershäuser furthers his views and opinions on the origin and evolution of life. He reviews some of his previous work and presents an alternative to the dominant ‘Ancient RNA world’ hypothesis. The alternative views he previously generated are much expanded in this manuscript. In light of recent research developments and argumentation (some of it reviewed), his views should be considered a welcome addition to the many ideas that populate the “origin of life” field of inquiry that counter the dominant paradigm. I have however a number of quibbles that if addressed could increase the accuracy, value and impact of the manuscript. I must note that a careful evaluation of all facets requires expertise in a multitude of disciplines (from prebiotic chemistry and structural biology to evolutionary bioinformatics and biochemistry) and considerable time, none of which I possess. Therefore, my comments will be slanted by my own expertise and will only serve the author as a partial devil’s advocate effort General commentary Section 1. The place of RNA in LUCA (page 2): In search of features that are more conserved (carrying deep phylogenetic memory) than the sequence of genes, Wächtershäuser focuses on a paper of his in Systematic and Applied Microbiology (1998) that uses gene content and order of microbial genomes to make inferences about the last universal common ancestor (LUCA) of cellular life. -
Cometary Panspermia a Radical Theory of Life’S Cosmic Origin and Evolution …And Over 450 Articles, ~ 60 in Nature
35 books: Cosmic origins of life 1976-2020 Physical Sciences︱ Chandra Wickramasinghe Cometary panspermia A radical theory of life’s cosmic origin and evolution …And over 450 articles, ~ 60 in Nature he combined efforts of generations supporting panspermia continues to Prof Wickramasinghe argues that the seeds of all life (bacteria and viruses) Panspermia has been around may have arrived on Earth from space, and may indeed still be raining down some 100 years since the term of experts in multiple fields, accumulate (Wickramasinghe et al., 2018, to affect life on Earth today, a concept known as cometary panspermia. ‘primordial soup’, referring to Tincluding evolutionary biology, 2019; Steele et al., 2018). the primitive ocean of organic paleontology and geology, have painted material not-yet-assembled a fairly good, if far-from-complete, picture COMETARY PANSPERMIA – cultural conceptions of life dating back galactic wanderers are normal features have argued that these could not into living organisms, was first of how the first life on Earth progressed A SOLUTION? to the ideas of Aristotle, and that this of the cosmos. Comets are known to have been lofted from the Earth to a coined. The question of how from simple organisms to what we can The word ‘panspermia’ comes from the may be the source of some of the have significant water content as well height of 400km by any known process. life’s molecular building blocks see today. However, there is a crucial ancient Greek roots ‘sperma’ meaning more hostile resistance the idea of as organics, and their cores, kept warm Bacteria have also been found high in spontaneously assembled gap in mainstream understanding - seed, and ‘pan’, meaning all. -
Quantification of Peptide Bond Types in Human Proteome Indicates How
ics om & B te i ro o P in f f o o r l m Nahalka, J Proteomics Bioinform 2011, 4:8 a Journal of a n t r i c u s DOI: 10.4172/jpb.1000184 o J ISSN: 0974-276X Proteomics & Bioinformatics Research Article Article OpenOpen Access Access Quantification of Peptide Bond Types in Human Proteome Indicates How DNA Codons were Assembled at Prebiotic Conditions Jozef Nahalka1,2* 1Institute of Chemistry, Center for Glycomics, Slovak Academy of Sciences, Dúbravská cesta 9, SK-84538 Bratislava, Slovak Republic 2Institute of Chemistry, Center of excellence for white-green biotechnology, Slovak Academy of Sciences, Trieda Andreja Hlinku 2, SK-94976 Nitra, Slovak Republic Abstract [GADV]-protein world hypothesis [1] leaded me to quantification of decapeptides assembled from G, A, V, D in human proteome. The G, A, V, and D amino acids were related to the nucleotides Guanine (g), Cystosine (c), Uracil (u), and Adenine (a). The search revealed agreement with the genetic code. The types of prebiotic peptide bonds represent probably the first selection power that established the base order in the codons. The genetic code underwent three phases of formation, which explain why modern codons have their particular order of nucleotides: the monobase, dibase and the modern phase (tribase). Sequence alignments and 3D structures of aminoacyl-tRNA synthetases confirm the depicted picture of “relatedness” and the picture indicates how “relatedness” is used by aminoacyl-tRNA synthetases for navigation into and within of the C-terminal anticodon-binding domain. The findings presented here illustrate the novel concept of possible translation of the amino acid sequence into a nucleotide sequence that can be in interactive or contrary mode regarding to desired protein-RNA interactions. -
The Difficult Case of an RNA-Only Origin of Life
Emerging Topics in Life Sciences (2019) 3 469–475 https://doi.org/10.1042/ETLS20190024 Perspective The difficult case of an RNA-only origin of life Kristian Le Vay and Hannes Mutschler Max-Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany Downloaded from https://portlandpress.com/emergtoplifesci/article-pdf/3/5/469/859756/etls-2019-0024c.pdf by Max-Planck-Institut fur Biochemie user on 28 November 2019 Correspondence: Hannes Mutschler ([email protected]) The RNA world hypothesis is probably the most extensively studied model for the emergence of life on Earth. Despite a large body of evidence supporting the idea that RNA is capable of kick-starting autocatalytic self-replication and thus initiating the emergence of life, seemingly insurmountable weaknesses in the theory have also been highlighted. These problems could be overcome by novel experimental approaches, including out-of- equilibrium environments, and the exploration of an early co-evolution of RNA and other key biomolecules such as peptides and DNA, which might be necessary to mitigate the shortcomings of RNA-only systems. The conjecture that life on Earth evolved from an ‘RNA World’ remains one of the most popular hypotheses for abiogenesis, even 60 years after Alex Rich first put the idea forward [1]. For some, evi- dence based upon ubiquitous molecular fossils and the elegance of the idea that RNA once had a dual role as information carrier and prebiotic catalyst provide overwhelming support for the theory. Nevertheless, doubts remain surrounding the chemical evolution of an RNA world, whose classical scenario is based on a temporal sequence of nucleotide formation, enzyme-free polymerisation/replica- tion, recombination, encapsulation in lipid vesicles (or other compartments), evolution of ribozymes and finally the innovation of the genetic code and its translation (Figure 1)[2,3]. -
Chemical Evolution Theory of Life's Origins the Lattimer, AST 248, Lecture 13 – P.2/20 Organics
Chemical Evolution Theory of Life's Origins 1. the synthesis and accumulation of small organic molecules, or monomers, such as amino acids and nucleotides. • Production of glycine (an amino acid) energy 3HCN+2H2O −→ C2H5O2N+CN2H2. • Production of adenine (a base): 5 HCN → C5H5N5, • Production of ribose (a sugar): 5H2CO → C5H10O5. 2. the joining of these monomers into polymers, including proteins and nucleic acids. Bernal showed that clay-like materials could serve as sites for polymerization. 3. the concentration of these molecules into droplets, called protobionts, that had chemical characteristics different from their surroundings. This relies heavily on the formation of a semi-permeable membrane, one that allows only certain materials to flow one way or the other through it. Droplet formation requires a liquid with a large surface tension, such as water. Membrane formation naturally occurs if phospholipids are present. 4. The origin of heredity, or a means of relatively error-free reproduction. It is widely, but not universally, believed that RNA-like molecules were the first self-replicators — the RNA world hypothesis. They may have been preceded by inorganic self-replicators. Lattimer, AST 248, Lecture 13 – p.1/20 Acquisition of Organic Material and Water • In the standard model of the formatio of the solar system, volatile materials are concentrated in the outer solar system. Although there is as much carbon as nearly all other heavy elements combined in the Sun and the bulk of the solar nebula, the high temperatures in the inner solar system have lead to fractional amounts of C of 10−3 of the average. -
Evolutionary Processes Transpiring in the Stages of Lithopanspermia Ian Von Hegner
Evolutionary processes transpiring in the stages of lithopanspermia Ian von Hegner To cite this version: Ian von Hegner. Evolutionary processes transpiring in the stages of lithopanspermia. 2020. hal- 02548882v2 HAL Id: hal-02548882 https://hal.archives-ouvertes.fr/hal-02548882v2 Preprint submitted on 5 Aug 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. HAL archives-ouvertes.fr | CCSD, April 2020. Evolutionary processes transpiring in the stages of lithopanspermia Ian von Hegner Aarhus University Abstract Lithopanspermia is a theory proposing a natural exchange of organisms between solar system bodies as a result of asteroidal or cometary impactors. Research has examined not only the physics of the stages themselves but also the survival probabilities for life in each stage. However, although life is the primary factor of interest in lithopanspermia, this life is mainly treated as a passive cargo. Life, however, does not merely passively receive an onslaught of stress from surroundings; instead, it reacts. Thus, planetary ejection, interplanetary transport, and planetary entry are only the first three factors in the equation. The other factors are the quality, quantity, and evolutionary strategy of the transported organisms. -
Origins of Life in the Universe Zackary Johnson
11/4/2007 Origins of Life in the Universe Zackary Johnson OCN201 Fall 2007 [email protected] Zackary Johnson http://www.soest.hawaii.edu/oceanography/zij/education.html Uniiiversity of Hawaii Department of Oceanography Class Schedule Nov‐2Originsof Life and the Universe Nov‐5 Classification of Life Nov‐7 Primary Production Nov‐9Consumers Nov‐14 Evolution: Processes (Steward) Nov‐16 Evolution: Adaptation() (Steward) Nov‐19 Marine Microbiology Nov‐21 Benthic Communities Nov‐26 Whale Falls (Smith) Nov‐28 The Marine Food Web Nov‐30 Community Ecology Dec‐3 Fisheries Dec‐5Global Ecology Dec‐12 Final Major Concepts TIMETABLE Big Bang! • Life started early, but not at the beginning, of Earth’s Milky Way (and other galaxies formed) history • Abiogenesis is the leading hypothesis to explain the beginning of life on Earth • There are many competing theories as to how this happened • Some of the details have been worked out, but most Formation of Earth have not • Abiogenesis almost certainly occurred in the ocean 20‐15 15‐94.5Today Billions of Years Before Present 1 11/4/2007 Building Blocks TIMETABLE Big Bang! • Universe is mostly hydrogen (H) and helium (He); for Milky Way (and other galaxies formed) example –the sun is 70% H, 28% He and 2% all else! Abundance) e • Most elements of interest to biology (C, N, P, O, etc.) were (Relativ 10 produced via nuclear fusion Formation of Earth Log at very high temperature reactions in large stars after Big Bang 20‐13 13‐94.7Today Atomic Number Billions of Years Before Present ORIGIN OF LIFE ON EARTH Abiogenesis: 3 stages Divine Creation 1.