Origin Of Life Research Articles

From Precambrian Iron-Formation to Terraforming Mars: The JIMES Expedition to Santorini

ABSTRACTThe iron embayments at Santorini, Greece, have long been considered by geologists to be the most useful modern environment for understanding variables related to precipitation of Precambrian iron-formation. To help understand the rock record, the embayments were studied almost monthly for a year to assess seasonal variations in iron bacteria and diatoms along with mineralogy, weather, water chemistry, and ecology. Unidentified red rods dominated and accounted for most ferrihydrite production. Diatom abundance was seasonal, including Parlibellus delognei which produces molecular oxygen within iron-coated sheaths. The gross structures of the microbial iron precipitates were in the form of rods, spheres, and braids. Speculations resulting from our observations suggest that life's origin could have been intimately related to chemical/physical processes occurring where volcanic sources discharged iron through highly porous siliceous substrates and into the primitive ocean. The diverse community also provides a potentially useful ecosystem for Mars terraforming experiments.

A roadmap for a computational theory of the value of information in originof life questions

Information plays a critical role in complex biological systems. Complex systems like immune systems and ant colonies co-ordinate heterogeneous components in a decentralized fashion. How do these distributed decentralized systems function? One key component is how these complex systems efficiently process information. These complex systems have an architecture for integrating and processing information coming in from various sources and points to the value of information in the functioning of different complex biological systems. This article proposes a role for information processing in questions around the origin of life and suggests how computational simulations may yield insights into questions related to the origin of life. Such a computational model of the origin of life would unify thermodynamics with information processing and we would gain an appreciation of why proteins and nucleotides evolved as the substrate of computation and information processing in living systems that we see on Earth. Answers to questions like these may give us insights into non-carbon based forms of life that we could search for outside Earth. We hypothesize that carbon-based life forms are only one amongst a continuum of systems in the universe. Investigations into the role of computational substrates that allow information processing is important and could yield insights into: 1) novel non-carbon based computational substrates that may have life-like properties, and 2) how life may have actually originated from non-life on Earth. Life may exist as a continuum between non-life and life and we may have to revise our notion of life and how common it is in the universe. Looking at life or phenomenon through the lens of information theory may yield a broader view of life.

Fatty acids' double role in the prebiotic formation of a hydrophobic dipeptide.

In search of a connection between prebiotic peptide chemistry and lipid compartments, the reaction of a 5(4H)-oxazolone with leucinamide was extensively explored under buffered aqueous conditions, where diverse amphiphiles and surfactants could form supramolecular assemblies. Significant increases in yield and changes in stereoselectivity were observed when fatty acids exceeded their critical aggregation concentration, self-assembling into vesicles in particular. This effect does not take place below the fatty acid solubility limit, or when other anionic amphiphiles/surfactants are used. Data from fluorimetric and Langmuir trough assays, complementary to the main HPLC results reported here, demonstrate that the dipeptide product co-localizes with fatty acid bilayers and monolayers. Additional experiments in organic solvents suggest that acid-base catalysis operates at the water-aggregate interface, linked to the continuous proton exchange dynamics that fatty acids undergo at pH values around their effective pKa. These simple amphiphiles could therefore play a dual role as enhancers of peptide chemistry under prebiotic conditions, providing soft and hydrophobic organic domains through self-assembly and actively inducing catalysis at their interface with the aqueous environment. Our results support a systems chemistry approach to life's origin.

A Strategy for Origins of Life Research.

Contents1. Introduction1.1. A workshop and this document1.2. Framing origins of life science1.2.1. What do we mean by the origins of life (OoL)?1.2.2. Defining life1.2.3. How should we characterize approaches to OoL science?1.2.4. One path to life or many?2. A Strategy for Origins of Life Research2.1. Outcomes—key questions and investigations2.1.1. Domain 1: Theory2.1.2. Domain 2: Practice2.1.3. Domain 3: Process2.1.4. Domain 4: Future studies2.2. EON Roadmap2.3. Relationship to NASA Astrobiology Roadmap and Strategy documents and the European AstRoMap Appendix I Appendix II Supplementary Materials References

Physical Organic Chemistry and the Origin of Life Problem: A Personal Perspective

AbstractThe origin of life (OOL) question might be considered physical organic chemistry’s ultimate challenge, yet despite continuing efforts over close to a century, the problem remains unresolved. In this personal perspective, I discuss some aspects of that challenge, and argue that notwithstanding the general perception that physical organic chemistry is a research area in decline, the discipline was, and continues to be, the most relevant one for tackling the OOL problem. Systems chemistry, a newly emergent branch of physical organic chemistry, which, inter alia, deals with replicating chemical systems and the networks they establish, reveals that physical organic chemistry, though in different guise, is alive and kicking. The broad direction ahead seems illuminated.

What if … We came from space?

All our best theories about the origins of life have one thing in common: it started on Earth. But maybe it didn't – maybe we were all aliens once

Researchers may have solved origin-of-life conundrum

Researchers may have solved origin-of-life conundrum

The origin of life from a paleontological perspective, a review

Aunque no puede decirse con precision cuando se origino la vida en el planeta hay evidencia de que ocurrio poco despues de que la Tierra se enfrio, cuando las temperaturas permitieron la existencia de agua liquida y el desarrollo de la hidrosfera primitiva. El registro fosil aporta datos de que la vida existio mucho antes de los 3400 Ma. Para entender el origen de la vida se ha recurrido al estudio de trazas geoquimicas analizando la presencia de carbono organico y a la evidencia isotopica que sugieren actividad microbiana. La corteza litosferica mas antigua, que data del Eoarqueano, se encuentra en la isla de Akilia y en el cinturon Isua Greenstone al suroeste de Groenlandia, pero el microfosil mas antiguo proviene de pedernal de la Formacion Strelley Pool en Pilbara, Australia, con una edad de 3430 Ma. En el campo de la Paleontologia es necesario reevaluar los afloramientos del Eoarqueano y Paleoarqueano utilizando las nuevas tecnologias desde una perspectiva multidisciplinaria para aportar datos respecto a cuando ocurrio el origen de la vida

Paradoxes in the origin of life.

Paradoxes in the origin of life.

Ribozyme May Hint At The Origin Of Life

Ribozyme May Hint At The Origin Of Life

Origin of life: The first spark

David Deamer welcomes a synthesis of what we know about the origins of life, as told by a master in the field.

Evolution. Energy at life's origin.

Analysis of the bioenergetics of primitive organisms suggests that life began at hydrothermal vents

The force-from-lipid (FFL) principle of mechanosensitivity, at large and in elements.

Focus on touch and hearing distracts attention from numerous subconscious force sensors, such as the vital control of blood pressure and systemic osmolarity, and sensors in nonanimals. Multifarious manifestations should not obscure invariant and fundamental physicochemical principles. We advocate that force from lipid (FFL) is one such principle. It is based on the fact that the self-assembled bilayer necessitates inherent forces that are large and anisotropic, even at life's origin. Functional response of membrane proteins is governed by bilayer force changes. Added stress can redirect these forces, leading to geometric changes of embedded proteins such as ion channels. The FFL principle was first demonstrated when purified bacterial mechanosensitive channel of large conductance (MscL) remained mechanosensitive (MS) after reconstituting into bilayers. This key experiment has recently been unequivocally replicated with two vertebrate MS K2p channels. Even the canonical Kv and the Drosophila canonical transient receptor potentials (TRPCs) have now been shown to be MS in biophysical and in physiological contexts, supporting the universality of the FFL paradigm. We also review the deterministic role of mechanical force during stem cell differentiation as well as the cell-cell and cell-matrix tethers that provide force communications. In both the ear hair cell and the worm's touch neuron, deleting the cadherin or microtubule tethers reduces but does not eliminate MS channel activities. We found no evidence to distinguish whether these tethers directly pull on the channel protein or a surrounding lipid platform. Regardless of the implementation, pulling tether tenses up the bilayer. Membrane tenting is directly visible at the apexes of the stereocilia.

A phylogenetic approach to the early evolution of autotrophy: the case of the reverse TCA and the reductive acetyl-CoA pathways.

In recent decades, a number of hypotheses on the autotrophic origin of life have been presented. These proposals invoke the emergence of reaction networks leading from CO or CO₂ to the organic molecules required for life. It has also been suggested that the last (universal) common ancestor (LCA or LUCA) of all extant cell lineages was a chemolitho-autotrophic thermophilic anaerobe. The antiquity of some carbon fixation pathways, the phylogenetic basal distribution of some autotrophic organisms, and the catalytic properties of iron-sulfur minerals have been advanced in support of these ideas. Here we critically examine the phylogenetic distribution and evolution of enzymes that are essential for two of the most ancient autotrophic means of metabolism: the reductive tricarboxylic acid (rTCA) cycle and the reductive acetyl-CoA pathway. Phylogenetic analysis of citryl-CoA synthetase and of citryl-CoA lyase, key enzymatic components of the rTCA cycle, and of CO dehydrogenase/acetyl-CoA synthase, a key enzyme in the reductive acetyl-CoA pathway, revealed that all three enzymes have undergone major lateral transfer events and therefore cannot be used as proof of the LCA's metabolic abilities nor as evidence of an autotrophic origin of life.

Feeling the hidden mechanical forces in lipid bilayer is an original sense.

Life's origin entails enclosing a compartment to hoard material, energy, and information. The envelope necessarily comprises amphipaths, such as prebiotic fatty acids, to partition the two aqueous domains. The self-assembled lipid bilayer comes with a set of properties including its strong anisotropic internal forces that are chemically or physically malleable. Added bilayer stretch can alter force vectors on embedded proteins to effect conformational change. The force-from-lipid principle was demonstrated 25 y ago when stretches opened purified Escherichia coli MscL channels reconstituted into artificial bilayers. This reductionistic exercise has rigorously been recapitulated recently with two vertebrate mechanosensitive K(+) channels (TREK1 and TRAAK). Membrane stretches have also been known to activate various voltage-, ligand-, or Ca(2+)-gated channels. Careful analyses showed that Kv, the canonical voltage-gated channel, is in fact exquisitely sensitive even to very small tension. In an unexpected context, the canonical transient-receptor-potential channels in the Drosophila eye, long presumed to open by ligand binding, is apparently opened by membrane force due to PIP2 hydrolysis-induced changes in bilayer strain. Being the intimate medium, lipids govern membrane proteins by physics as well as chemistry. This principle should not be a surprise because it parallels water's paramount role in the structure and function of soluble proteins. Today, overt or covert mechanical forces govern cell biological processes and produce sensations. At the genesis, a bilayer's response to osmotic force is likely among the first senses to deal with the capricious primordial sea.

The origin of life: what we know, what we can know and what we will never know

The origin of life (OOL) problem remains one of the more challenging scientific questions of all time. In this essay, we propose that following recent experimental and theoretical advances in systems chemistry, the underlying principle governing the emergence of life on the Earth can in its broadest sense be specified, and may be stated as follows: all stable (persistent) replicating systems will tend to evolve over time towards systems of greater stability. The stability kind referred to, however, is dynamic kinetic stability, and quite distinct from the traditional thermodynamic stability which conventionally dominates physical and chemical thinking. Significantly, that stability kind is generally found to be enhanced by increasing complexification, since added features in the replicating system that improve replication efficiency will be reproduced, thereby offering an explanation for the emergence of life's extraordinary complexity. On the basis of that simple principle, a fundamental reassessment of the underlying chemistry–biology relationship is possible, one with broad ramifications. In the context of the OOL question, this novel perspective can assist in clarifying central ahistoric aspects of abiogenesis, as opposed to the many historic aspects that have probably been forever lost in the mists of time.

In Retrospect: The Origin of Life

Clifford P. Brangwynne and Anthony A. Hyman celebrate the first book to plausibly suggest how life began.

Clues to the origin of life from OSIRIS-REx

Clues to the origin of life from OSIRIS-REx

Kick-starting the origin of life: Comment on “Formamide and the origin of life” by R. Saladino, C. Crestini, S. Pino, G. Costanzo and E. Di Mauro

Kick-starting the origin of life: Comment on “Formamide and the origin of life” by R. Saladino, C. Crestini, S. Pino, G. Costanzo and E. Di Mauro

A “warm formamide” scenario for the origins of life might not be so hot: Comment on “Formamide and the origin of life” by E. Di Mauro et al.

In this review, Saladino et al. present an intriguing hypothesis surrounding the role of formamide in the originsof life on Earth, backed by experimental results supporting each step from formamide to RNA polymers [1]. The overall premise is that, from formamide and inorganic phosphate, RNA molecules over 100 nucleotides in length canbe produced. In addition, many carboxylic acids likely relevant to prebiotic metabolism are formed along the way. Thus, from a rather simple organic molecule that has been observed in outer space (formamide), you can generatemany of the compounds necessary for the origins of life. However, because high temperatures (160 C) are requiredfor the formamide reactions, it remains unclear where the warm formamide scenario could have occurred.Low-temperature, aqueous hydrogen counter to the observation that all protein-catalyzed ligation and polymerization reactions of RNA and DNA requireactivated substrates. Detailed mechanistic studies of the reported reactions are warranted and could provide important insights for understanding the chemistry behind the origins of life.Because the authors have produced many of the experimental results supporting their hypothesis, they coulddemonstrate the validity of their hypothesis by converting formamide into 100 nucleotide RNA oligomers, usingthe products of one reaction as the reactants for the next reaction, under specific conditions plausible on the pre-bioticEarth. Such a demonstration would represent a milestone for our understanding of the origins of life.cyanide-based prebiotic chemistry that we know actually happened has beenshown to produce many of the molecules invoked in the formamide hypothesis: amino acids, carboxylic acids, sugaracids, and nucleobases have all been found in meteorites recovered on Earth [e.g. [24]], providing a plausible routefor their synthesis and delivery. In contrast, a large portion of the formamide hypothesis is based on relatively high-temperature reactions. A plausible milieu for high-temperature reactions with concentrated formamide is yet to bedescribed, and is critical for this hypothesis to be validated. Hydrothermal vents are attractive heat sources, and the higher boiling point of formamide has been invoked as a mechanism to concentrate it from an aqueous solution.Unless the water can actually evaporate, however, there would be no net enrichment. For example, in the context of a deep-sea vent, any water removed by heating would be quickly replaced.Some of the individual reactions underpinning the present hypothesis [1] have been met with skepticism becausethey go against conventional wisdom. To name a few of the surprising results: the observation that nucleosides can beconverted to cyclic phosphates when heated in the presence of minerals and inorganic phosphate [5]; that 35 cGMPand cAMP nucleotides polymerize rapidly into RNA oligomers, even in the absence of monovalent counterions [6];and that end-to-end ligation reactions between RNA oligomers occur in essentially pure water, without requiring any activating groups or counterions [7,8]. Because the polymerization reactions are simply transesterification reactions,that they readily occur in the absence of cations makes one wonder why nearly all ribozyme-catalyzed transesterification reactions are metal-ion dependent; similarly, that the end-to-end ligation reactions do not require activation runs.