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How did specific useful protein sequences arise from simpler molecules at the origin of life? This seemingly needle-in-a-haystack problem has remarkably close resemblance to the old Protein Folding Problem, for which the solution is now known from statistical physics. Based on the logic that Origins must have come only after there was an operative evolution mechanism-which selects on phenotype, not genotype-we give a perspective that proteins and their folding processes are likely to have been the primary driver of the early stages of the origin of life.

The origin of life must have been preceded by Darwin-like evolutionary dynamics that could propagate it. How did that adaptive dynamics arise? And from what prebiotic molecules? Using evolutionary invasion analysis, we develop a universal framework for describing any origin story for evolutionary dynamics. We find that cooperative autocatalysts, i.e. autocatalysts whose per-unit reproductive rate grows as their population increases, have the special property of being able to cross a barrier that separates their initial degradation-dominated state from a growth-dominated state with evolutionary dynamics. For some model parameters, this leap to persistent propagation is likely, not rare. We apply this analysis to the Foldcat Mechanism, wherein peptides fold and help catalyse the elongation of each other. Foldcats are found to have cooperative autocatalysis and be capable of emergent evolutionary dynamics.

We report simulation studies of 33 single intrinsically disordered proteins (IDPs) using coarse-grained bead-spring models where interactions among different amino acids are introduced through a hydropathy matrix and additional screened Coulomb interaction for the charged amino acid beads. Our simulation studies of two different hydropathy scales (HPS1, HPS2) [Dignon et al., PLoS Comput. Biol. 14, e1005941 (2018); Tesei et al. Proc. Natl. Acad. Sci. U. S. A. 118, e2111696118 (2021)] and the comparison with the existing experimental data indicate an optimal interaction parameter ϵ = 0.1 and 0.2 kcal/mol for the HPS1 and HPS2 hydropathy scales. We use these best-fit parameters to investigate both the universal aspects as well as the fine structures of the individual IDPs by introducing additional characteristics. (i) First, we investigate the polymer-specific scaling relations of the IDPs in comparison to the universal scaling relations [Bair et al., J. Chem. Phys. 158, 204902 (2023)] for the homopolymers. By studying the scaled end-to-end distances ⟨ R N 2 ⟩ / (2 L ℓ p ) and the scaled transverse fluctuations l ̃ ⊥ 2 = ⟨ l ⊥ 2 ⟩ / L , we demonstrate that IDPs are broadly characterized with a Flory exponent of ν ≃ 0.56 with the conclusion that conformations of the IDPs interpolate between Gaussian and self-avoiding random walk chains. Then, we introduce (ii) Wilson charge index (W) that captures the essential features of charge interactions and distribution in the sequence space and (iii) a skewness index (S) that captures the finer shape variation of the gyration radii distributions as a function of the net charge per residue and charge asymmetry parameter. Finally, our study of the (iv) variation of ⟨Rg⟩ as a function of salt concentration provides another important metric to bring out finer characteristics of the IDPs, which may carry relevant information for the origin of life. [ABSTRACT FROM AUTHOR]

The path from lifes origin to the emergence of the eukaryotic cell was long and complex, and as such it is rarely treated in one publication. Here, we offer a sketch of this path, recognizing that there are points of disagreement and that many transitions are still shrouded in mystery. We assume life developed within microchambers of an alkaline hydrothermal vent system. Initial simple reactions were built into more sophisticated reflexively autocatalytic food-generated networks (RAFs), laying the foundation for lifes anastomosing metabolism, and eventually for the origin of RNA, which functioned as a genetic repository and as a catalyst (ribozymes). Eventually, protein synthesis developed, leading to lifes biology becoming dominated by enzymes and not ribozymes. Subsequent enzymatic innovation included ATP synthase, which generates ATP, fueled by the proton gradient between the alkaline vent flux and the acidic sea. This gradient was later internalized via the evolution of the electron transport chain, a preadaptation for the subsequent emergence of the vent creatures from their microchamber cradles. Differences between bacteria and archaea suggests cellularization evolved at least twice. Later, the bacterial development of oxidative phosphorylation and the archaeal development of proteins to stabilize its DNA laid the foundation for the merger that led to the formation of eukaryotic cells.

Developing and validating a perspective scale of a student’s acceptance or rejection of the evolution and abiogenesis theories regarding the origin of life and biodiversity is potentially significant, particularly considering the importance of these theories in the biology curriculum. Existing instruments, by their nature, may not allow us to fully understand student perspectives on complex and comprehensive biological theories. Therefore, we believe it is necessary to identify belief-based perspectives that significantly influence the acceptance or rejection of these theories, in addition to students’ perspectives on the theories of abiogenesis and evolution. In this context, we believe that a developed instrument can provide additional evidence to researchers who seek to integrate the information obtained from students’ perspectives into educational practices. This article explains the development and validation of the Perspective Scale on the Origin of Life and Biodiversity (PSOLB), a 25-item Likert scale instrument designed to assess students’ belief-based perspectives on the origin of life and biodiversity. Moreover, the potential contributions and significance of the research findings for pedagogical research and practices are emphasised, along with recommendations for the future use of the scale. [ABSTRACT FROM AUTHOR]

The origin of life and its evolution are generally taught as occurring by abiogenesis and gene-centric neo-Darwinism. Significant biological evolutionary changes are preserved and given direction (descent with modification) by Darwin's (Spencer's) natural selection by survival of the fittest. Only survival of the fittest (adapted/broadened) is available to provide a 'naturalistic' direction to prefer one outcome/reaction over another for abiogenesis. Thus, assembly of first life must reach some threshold (the first minimal cell) before 'survival of the fittest' (the only naturalistic explanation available) can function as Darwin proposed for biological change. We propose the novel concept that the requirement for co-origination of vitamins with enzymes is a fundamental, but overlooked, problem that survival of the fittest (even broadly redefined beyond Darwin) cannot reasonably overcome. We support this conclusion with probability calculations. We focus on the stage of evolution involving the transition from non-life to the first, minimal living cell. We show that co-origination of required biochemical processes makes the origin of life probabilistically absurdly improbable even when all assumptions are chosen to unreasonably favor evolutionary theories. [ABSTRACT FROM AUTHOR]

Heterocycles have not been detected in the interstellar medium (ISM) yet. However, the direct involvement of some pentagonal heterocycles within the formation of key biomolecules for the origin of life makes the search for these systems in the ISM relevant for understanding whether some of the bricks of life could be formed in the ISM. We have explored the possible formation of the simple heterocycle furan (c-C |$_{4}$| H |$_{4}$| O) under interstellar conditions, through the reaction between two interstellar species, |$\mathrm{syn}$| -vinyl alcohol (⁠|$\mathrm{syn}$| -VA) and the CCH radical. We employed state-of-the-art quantum-chemical calculations to elucidate the reaction mechanism between the reaction of CCH radical and |$\mathrm{syn}$| -VA. Kinetic simulations were carried out aiming to quantitatively assess the viability of this reaction in the ISM. We have found a reaction pathway to furan where all energy barriers are submerged. However, the formation of this heterocycle is not feasible because the intermediates leading to furan can evolve through more favourable routes. In contrast, we have found viable pathways for the formation of the four isomers of 1-butenol-3-yne (HCCCHCHOH) (Z - |$\mathrm{syn}$|⁠ , E - |$\mathrm{syn}$|⁠ , E - |$\mathrm{anti}$|⁠ , and Z - |$\mathrm{anti}$|⁠), which thus are promising species to be detected in the ISM. Our theoretical work indicates that the four isomers of 1-butenol-3-yne should be present in the ISM because the precursors are known interstellar species, and the kinetic simulations indicate that their formation is very likely. We then encourage the observational search of these molecules in the ISM. [ABSTRACT FROM AUTHOR]

Mutualisms are interactions that benefit all species involved. It has been widely investigated in neighbouring subjects, such as biology, ecology, sociology, and economics. However, such a reciprocal relationship in synthetic chemical systems has rarely been studied. Here, we demonstrate a mutualistic synthesis where byproducts from two orthogonal chemical reactions aid each other′s production. Disulfide exchange and hydrazone exchange were chosen to generate two dynamic combinatorial libraries. A minor tetrameric macrocycle from the active disulfide library was quantitatively amplified in the presence of the hydrazone library. This incorporation also turned on the previously inert hydrazone reaction, producing a linear species that formed a "handcuffs" catenane with the disulfide tetramer. These findings not only lend robust support to the hypothesis of "RNA‐peptide coevolution" for the origin of life but also broaden the scope of synthetic chemistry, highlighting the untapped potential of minor products from different reactions. Additionally, the co‐self‐assembly of these mutualistic entities to form supramolecular structures opens new avenues for future development of composite nanosystems with synergistic properties. [ABSTRACT FROM AUTHOR]

In the boundless landscape of scientific exploration, there exists a hidden, yet easily accessible, dimension that has often not only intrigued and puzzled researchers but also provided the key. This dimension is chirality, the property that describes the handedness of objects. The influence of chirality extends across diverse fields of study from the parity violation in electroweak interactions to the extremely large macroscopic systems such as galaxies. In this opinion piece, we will delve into the power of chirality in scientific exploration by examining some examples that, at different scales, demonstrate its role as a key to a better understanding of our world. Our goal is to incite researchers from all fields to seek, implement and utilize chirality in their research. Going this extra mile might be more rewarding than it seems at first glance, in particular with regard to the increasing demand for new functional materials in response to the contemporary scientific and technological challenges we are facing. This article is part of the theme issue 'Celebrating the 15th anniversary of the Royal Society Newton International Fellowship'. [ABSTRACT FROM AUTHOR]

Encapsulating biological and non-biological materials in lipid vesicles presents significant potential in both industrial and academic settings. When smaller than 100 nm, lipid vesicles and lipid nanoparticles are ideal vehicles for drug delivery, facilitating the delivery of payloads, improving pharmacokinetics, and reducing the off-target effects of therapeutics. When larger than 1 μm, vesicles are useful as model membranes for biophysical studies, as synthetic cell chassis, as bio-inspired supramolecular devices, and as the basis of protocells to explore the origin of life. As applications of lipid vesicles gain prominence in the fields of nanomedicine, biotechnology, and synthetic biology, there is a demand for advanced technologies for their controlled construction, with microfluidic methods at the forefront of these developments. Compared to conventional bulk methods, emerging microfluidic methods offer advantages such as precise size control, increased production throughput, high encapsulation efficiency, user-defined membrane properties (i.e., lipid composition, vesicular architecture, compartmentalisation, membrane asymmetry, etc.), and potential integration with lab-on-chip manipulation and analysis modules. We provide a review of microfluidic lipid vesicle generation technologies, focusing on recent advances and state-of-the-art techniques. Principal technologies are described, and key research milestones are highlighted. The advantages and limitations of each approach are evaluated, and challenges and opportunities for microfluidic engineering of lipid vesicles to underpin a new generation of therapeutics, vaccines, sensors, and bio-inspired technologies are presented. [ABSTRACT FROM AUTHOR]

The origin of life (OoL) has always been a mysterious and challenging topic that puzzles human beings. Clay minerals have unique properties and wide distribution in early Earth environments. They can not only adsorb biological small molecules to catalyze their polymerization, but play an active role in the formation and evolution of protocells. In this review, the research progress on the interactions of clay minerals with biomolecules and protocells complex structures in the field of the OoL based on chemical evolution theory is summarized. The types, structures and properties of clay minerals, biological molecules and protocell models related to the OoL are introduced in detail. The mechanism of interaction between clay minerals and biological molecules, the construction of protocells and the role of clay minerals in the formation, structure and stability of protocells are systematically described. Finally, the future research priorities and challenges in the field of OoL based on clay minerals, biomolecules and protocells are discussed. It is aspired that this review can further advance the exploration of the OoL from a new perspective, and can also bring some interesting findings and ideas to the interdisciplinary research of materials, biology, chemistry and other related disciplines.Clay minerals have a variety of interactions with small biomolecules, which can be used as structural and functional templates to promote the organic synthesis of biomolecules and the formation and evolution of protocells, playing a non‐negligible role in the field of the OoL. [ABSTRACT FROM AUTHOR]

Understanding how cells communicated before the evolution of nervous systems in early metazoans is key to unraveling the origins of multicellular life. We focused on Trichoplax adhaerens, one of the earliest multicellular animals, to explore this question. Through screening a small compound library targeting G protein-coupled receptors (GPCRs), we found that Trichoplax exhibits distinctive rotational movements when exposed to epinephrine. Further studies suggested that, akin to those in humans, this basal organism also utilizes adrenergic signals to regulate its negative taxis behavior, with the downstream signaling pathway being more straightforward and efficient. Mechanistically, the binding of ligands activates downstream calcium signaling, subsequently modulating ciliary redox signals. This process ultimately regulates the beating direction of cilia, governing the coordinated movement of the organism. Our findings not only highlight the enduring presence of adrenergic signaling in stress responses during evolution but also underscore the importance of early metazoan expansion of GPCR families. This amplification empowers us with the ability to sense external cues and modulate cellular communication effectively. Basal multicellular animals are capable of coordinated movement despite the absence of an organize nervous system, though it remains unclear how cells communicate in these organisms. Here they use the placozoa Trichoplax to screen for active signaling molecules, and find that epinephrine can induce coordinated movement in these animals. [ABSTRACT FROM AUTHOR]

Low-molecular-mass organic chemicals are widely discussed as potential indicators of life in extraterrestrial habitats. However, demarcation lines between biotic chemicals and abiotic chemicals have been difficult to define. Here, we have analyzed the potential utility of the quantum chemical property, HOMO-LUMO gap (HLG), as a novel proxy variable of life, since a significant trend towards incrementally smaller HLGs has been described in the genetically encoded amino acids. The HLG is a zeroth-order predictor of chemical reactivity. Comparing a set of 134 abiotic organic molecules recovered from meteorites, with 570 microbial and plant secondary metabolites thought to be exclusively biotic, we found that the average HLG of biotic molecules was significantly narrower (−10.4 ± 0.9 eV versus −12.4 ± 1.6 eV), with an effect size of g = 1.87. Limitation to hydrophilic molecules (XlogP < 2) improved the separation of biotic from abiotic compounds (g = 2.52). The "hydrophilic reactivity" quadrant defined by |HLG| < 11.25 eV and XlogP < 2 was populated exclusively by 183 biotic compounds and 6 abiotic compounds, 5 of which were nucleobases. We conclude that hydrophilic molecules with small HLGs represent valuable indicators of biotic activity, and we discuss the evolutionary plausibility of this inference. [ABSTRACT FROM AUTHOR]

Obviously, the discussion of different factors that could have contributed to the origin of life and evolution is clear speculation, since there is no way of checking the validity of most of the related hypotheses in practice, as the corresponding events not only already happened, but took place in a very distant past. However, there are a few undisputable facts that are present at the moment, such as the existence of a wide variety of living forms and the abundant presence of intrinsically disordered proteins (IDPs) or hybrid proteins containing ordered domains and intrinsically disordered regions (IDRs) in all living forms. Since it seems that the currently existing living forms originated from a common ancestor, their variety is a result of evolution. Therefore, one could ask a logical question of what role(s) the structureless and highly dynamic but vastly abundant and multifunctional IDPs/IDRs might have in evolution. This study represents an attempt to consider various ideas pertaining to the potential roles of protein intrinsic disorder in the origin of life and evolution. [ABSTRACT FROM AUTHOR]

The central dogma of molecular biology can be conceptualised as the division of labour between templates and catalysts, where templates transmit genetic information, catalysts accelerate chemical reactions, and the information flows from templates to catalysts but not from catalysts to templates. How can template-catalyst division evolve in primordial replicating systems? A previous study has shown that even if the template-catalyst division does not provide an immediate fitness benefit, it can evolve through symmetry breaking between replicating molecules when the molecules are compartmentalised into protocells. However, cellular compartmentalisation may have been absent in primordial replicating systems. Here, we investigate whether cellular compartmentalisation is necessary for the evolution of the template-catalyst division via symmetry breaking using an individual-based model of replicators in a two-dimensional space. Our results show that replicators evolve the template-catalyst division via symmetry breaking when their diffusion constant is sufficiently high, a condition that results in low genetic relatedness between replicators. The evolution of the template-catalyst division reduces the risk of invasion by "cheaters," replicators that have no catalytic activities, encode no catalysts, but replicate to the detriment of local population growth. Our results suggest that the evolution of the template-catalyst division via symmetry breaking does not require cellular compartmentalization and is, instead, a general phenomenon in replicators with structured populations. Graphical Abstract [ABSTRACT FROM AUTHOR]

The principle of continuity demands the existence of prior molecular states and common ancestors responsible for extant macromolecular structure. Here, we focus on the emergence and evolution of loop prototypes – the elemental architects of protein domain structure. Phylogenomic reconstruction spanning superkingdoms and viruses generated an evolutionary chronology of prototypes with six distinct evolutionary phases defining a most parsimonious evolutionary progression of cellular life. Each phase was marked by strategic prototype accumulation shaping the structures and functions of common ancestors. The last universal common ancestor (LUCA) of cells and viruses and the last universal cellular ancestor (LUCellA) defined stem lines that were structurally and functionally complex. The evolutionary saga highlighted transformative forces. LUCA lacked biosynthetic ribosomal machinery, while the pivotal LUCellA lacked essential DNA biosynthesis and modern transcription. Early proteins therefore relied on RNA for genetic information storage but appeared initially decoupled from it, hinting at transformative shifts of genetic processing. Urancestral loop types suggest advanced folding designs were present at an early evolutionary stage. An exploration of loop geometric properties revealed gradual replacement of prototypes with α-helix and β-strand bracing structures over time, paving the way for the dominance of other loop types. AlphFold2-generated atomic models of prototype accretion described patterns of fold emergence. Our findings favor a ‛processual' model of evolving stem lines aligned with Woese's vision of a communal world. This model prompts discussing the 'problem of ancestors' and the challenges that lie ahead for research in taxonomy, evolution and complexity. [ABSTRACT FROM AUTHOR]

Development of chiral aggregation‐induced emission (AIE) materials toward hierarchical self‐assembly is crucial to reveal the origin and evolution of life. In this work, a pair of chiral AIE enantiomers is fabricated by attaching the typical AIE units to the chiral binaphthyl core via a single bond linkage. The AIE behavior is inherited from the introduced AIE unit while the binaphthyl unit can not only improve the photo‐physical properties but also provide the whole molecules with chirality. Moreover, as driven by the dipolar structure and chirality of the AIEgens, the hierarchical self‐assembly with different morphologies such as spheres, ribbons or fibers, flowers, and even bigger structures with various sizes can be dynamically monitored with the assembled time, which provided a favorable evidence to study the structural evolution from molecular level to a higher‐level structure. On the other hand, these AIEgens can act strong electronic acceptors due to the introduced AIE unit. By complexing them with strong electronic donors, the resulting intermolecular charge transfer can induce remarkable red emissions with the tunable properties which is much different from their individuals. This enabled it as a facile, economic, and flexible approach to develop organic photoelectric materials. [ABSTRACT FROM AUTHOR]

Evolution requires selection. Molecular/chemical/preDarwinian evolution is no exception. One molecule must be selected over another for molecular evolution to occur and advance. Evolution, however, has no goal. The laws of physics have no utilitarian desire, intent or proficiency. Laws and constraints are blind to "usefulness." How then were potential multi-step processes anticipated, valued and pursued by inanimate nature? Can orchestration of formal systems be physico-chemically spontaneous? The purely physico-dynamic self-ordering of Chaos Theory and irreversible non-equilibrium thermodynamic "engines of disequilibria conversion" achieve neither orchestration nor formal organization. Natural selection is a passive and after-the-fact-of-life selection. Darwinian selection reduces to the differential survival and reproduction of the fittest already-living organisms. In the case of abiogenesis, selection had to be 1) Active, 2) Pre-Function, and 3) Efficacious. Selection had to take place at the molecular level prior to the existence of non-trivial functional processes. It could not have been passive or secondary. What naturalistic mechanisms might have been at play? [ABSTRACT FROM AUTHOR]

This article analyzes the experience of childhood exile during the last Argentine dictatorship through two works by Laura Alcoba: "El azul de las abejas" (2014) and "La danza de la araña" (2018). These works allow for the analysis of the voice of the exiled woman and also that of her childhood, establishing a direct connection with Argentina's dictatorial past and the Southern Cone. The importance of representing childhood exile and how it is narrated after decades of silence through the learning of a foreign language in a distant country is highlighted. The text analyzes the use of autofiction in second-generation authors, relating it to the experience of being daughters of the disappeared during the dictatorship in Argentina. These authors use autofiction as a constant search for their origins and affiliations. The narrativization of the experience is presented as a link between testimonies and other discursive forms. Additionally, the "generational turn" is highlighted in which daughters reconfigure their own subjectivity through their narratives. On the other hand, the theme of exile and childhood is addressed in the works of Laura Alcoba, who narrates her experience as the daughter of Montoneros militants exiled in France. These works allow for reflection on exile as a form of "eradication of the subversive enemy" and the absence of exile narratives by women in the Western canon. The text analyzes the experience of childhood exile in two works by Laura Alcoba, "El azul" and "La danza". The importance of remnants from the protagonist's country of origin in her life is highlighted, such as her detained father's letters and her friend Amalia's stories. The narrator's overadaptation and agency in the midst of circumstances are mentioned. The impact of exile on identity and the construction of one's own memory is also addressed. The text discusses the experience of childhood exile in two works by Laura Alcoba. The concept of a "revolutionary family" is mentioned, referring to families whose ties are linked to political militancy. The communal life that occurred among the exiles and the importance of narration to shape and give meaning to the experience and recreate the past are highlighted. The displacement and "linguistic exile" that involves adapting to a new country and language are also mentioned. Finally, the importance of letters as objects that allow for the reconstruction of history and the presence of the absent is emphasized. The article analyzes the importance of letters as supports for memory and the material survival of exile. The possibility of configuring a "nomadic subjectivity" based on these remnants is highlighted, allowing for the delineation of new maps and cartographies of discontinuous times for surviving daughters. It is concluded that the works of the daughters emerge thanks to certain social and state political conditions that enable a listening and reception that did not exist before. These memorial narratives stand as another form of the political and contribute to the idea of collective memory. [Extracted from the article]

This article reviews all the major stages in the origins of life, from the emergence of matter in the initial Big Bang to the modern, civilized human being. On an immaterial level, it is proposed and explained how consciousness necessarily takes precedence over matter. Next, we explain how consciousness, with its ability to process information, selected the water molecule to breathe life into the periodic table of elements. We also explain why the notion of entropy allows us to evolve, "Die Entropie der Welt strebt einem Maximum zu" (second principle), and, therefore, takes precedence over the notion of energy, which, on the contrary, encourages us to preserve what we have, "Die Energie der Welt bleibt konstant" (first principle). This is followed by a discussion of the importance of quantum coherence and the need to rely on a second quantization formalism for a proper understanding of the physical–biochemical properties of water. Moreover, throughout the argument developed on the best and most fundamental things science has to offer, care is taken to link this knowledge to the great philosophies of the West (Greece), the East (China and India), and even to practices of a shamanic nature (Africa and America). Hence, finally, we propose reconsidering all musical practice within the framework of the diapason of water at a frequency of 429.62 Hz, as well as all therapeutic practice on the basis of seven clearly identified and established frameworks of thought. [ABSTRACT FROM AUTHOR]

Astronomical impacts by small solar system bodies (meteoroids, asteroids, comets, and transitional objects) are considered a mechanism for delivering amino acids and their polymerization to proteins in early Earth conditions. High‐pressure torsion (HPT) is a new methodology to simulate such impacts and clarify the behavior of biomolecules. Herein, two amino acids, crystalline L‐serine and L‐glutamic acid that are detected in meteorites, are processed by HPT and examined by ex situ X‐ray diffraction, Raman spectroscopy, nuclear magnetic resonance, Fourier‐transform infrared spectroscopy, and in situ mechanical shear testing. No polymerization, chemical reactions, or phase transformations are detected after HPT, indicating that the stability and presence of these two amino acids in meteorites are quite reasonable. However, some microstructural and mechanical changes like crystal size reduction to the nanometer level, crystal defect formation, lattice expansion by vacancy formation, and shear strength enhancement to the steady state are found which are similar to the behaviors reported in metals and ceramics after HPT processing. [ABSTRACT FROM AUTHOR]

The existence of life beyond Earth has long captivated humanity, and the study of extremophiles—organisms surviving and thriving in extreme environments—provides crucial insights into this possibility. Extremophiles overcome severe challenges such as enzyme inactivity, protein denaturation, and damage of the cell membrane by adopting several strategies. This feature article focuses on the molecular strategies extremophiles use to maintain the cell membrane's structure and fluidity under external stress. Key strategies include homeoviscous adaptation (HVA), involving the regulation of lipid composition, and osmolyte-mediated adaptation (OMA), where small organic molecules protect the lipid membrane under stress. Proteins also have direct and indirect roles in protecting the lipid membrane. Examining the survival strategies of extremophiles provides scientists with crucial insights into how life can adapt and persist in harsh conditions, shedding light on the origins of life. This article examines HVA and OMA and their mechanisms in maintaining membrane stability, emphasizing our contributions to this field. It also provides a brief overview of the roles of proteins and concludes with recommendations for future research directions. [ABSTRACT FROM AUTHOR]

The acquisition of new RNA functions through evolutionary processes was essential for the diversification of RNA-based primordial biology and its subsequent transition to modern biology. However, the mechanisms by which RNAs access new functions remain unclear. Do RNA enzymes need completely new folds to support new but related functions, or is reoptimization of the active site sufficient? What are the roles of neutral and adaptive mutations in evolutionary innovation? Here, we address these questions experimentally by focusing on the evolution of substrate specificity in RNA-catalyzed RNA assembly. We use directed in vitro evolution to show that a ligase ribozyme that uses prebiotically relevant 5'-phosphorimidazole-activated substrates can be evolved to catalyze ligation with substrates that are 5'-activated with the biologically relevant triphosphate group. Interestingly, despite catalyzing a related reaction, the new ribozyme folds into a completely new structure and exhibits promiscuity by catalyzing RNA ligation with both triphosphate and phosphorimidazole-activated substrates. Although distinct in sequence and structure, the parent phosphorimidazolide ligase and the evolved triphosphate ligase ribozymes can be connected by a series of point mutations where the intermediate sequences retain at least some ligase activity. The existence of a quasi-neutral pathway between these distinct ligase ribozymes suggests that neutral drift is sufficient to enable the acquisition of new substrate specificity, thereby providing opportunities for subsequent adaptive optimization. The transition from RNA-catalyzed RNA assembly using phosphorimidazole-activated substrates to triphosphate-activated substrates may have foreshadowed the later evolution of the protein enzymes that use monomeric triphosphates (nucleoside triphosphates, NTPs) for RNA synthesis. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is a neurodegenerative disorder with limited therapeutic options. Accordingly, new approaches for prevention and treatment are needed. One focus is the human microbiome, the consortium of microorganisms that live in and on us, which contributes to human immune, metabolic, and cognitive development and that may have mechanistic roles in neurodegeneration. AD and Alzheimer's disease–related dementias (ADRD) are recognized as spectrum disorders with complex pathobiology. AD/ADRD onset begins before overt clinical signs, but initiation triggers remain undefined. We posit that disruption of the normal gut microbiome in early life leads to a pathological cascade within septohippocampal and cortical brain circuits. We propose investigation to understand how early-life microbiota changes may lead to hallmark AD pathology in established AD/ADRD models. Specifically, we hypothesize that antibiotic exposure in early life leads to exacerbated AD-like disease endophenotypes that may be amenable to specific microbiological interventions. We propose suitable models for testing these hypotheses. [ABSTRACT FROM AUTHOR]

How do complex adaptive systems, such as life, emerge from simple constituent parts? In the 1990s, Walter Fontana and Leo Buss proposed a novel modeling approach to this question, based on a formal model of computation known as the λ calculus. The model demonstrated how simple rules, embedded in a combinatorially large space of possibilities, could yield complex, dynamically stable organizations, reminiscent of biochemical reaction networks. Here, we revisit this classic model, called AlChemy, which has been understudied over the past 30 years. We reproduce the original results and study the robustness of those results using the greater computing resources available today. Our analysis reveals several unanticipated features of the system, demonstrating a surprising mix of dynamical robustness and fragility. Specifically, we find that complex, stable organizations emerge more frequently than previously expected, that these organizations are robust against collapse into trivial fixed points, but that these stable organizations cannot be easily combined into higher order entities. We also study the role played by the random generators used in the model, characterizing the initial distribution of objects produced by two random expression generators, and their consequences on the results. Finally, we provide a constructive proof that shows how an extension of the model, based on the typed λ calculus, could simulate transitions between arbitrary states in any possible chemical reaction network, thus indicating a concrete connection between AlChemy and chemical reaction networks. We conclude with a discussion of possible applications of AlChemy to self-organization in modern programming languages and quantitative approaches to the origin of life. [ABSTRACT FROM AUTHOR]

Big impacts on the early Earth would have created highly reducing atmospheres that generated molecules needed for the origin of life, such as nitriles. However, such impactors could have been followed by collisions that were sufficiently big to vaporize the ocean and destroy any pre-existing life. Thus, a post-impact-reducing atmosphere that gives rise to life needs to be followed by a lack of subsequent sterilizing impacts for life to persist. We assume that prebiotic chemistry required a post-impact-reducing atmosphere. Then, using statistics for the impact history on Earth and the minimum impact mass needed to generate post-impact highly reducing atmospheres, we show that the median timing of impact-driven biopoiesis is favored early in the Hadean, ∼4.35 Ga. However, uncertainties are large because impact bombardment is stochastic, and so biopoiesis could have occurred between 4.45 and 3.9 Ga within 95% uncertainty. In an optimistic scenario for biopoiesis from post-impact-reducing atmospheres, we find that the origin of life is favorable in ∼90% of stochastic impact realizations. In our most pessimistic case, biopoiesis is still fairly likely (∼20% chance). This potentially bodes well for life on rocky exoplanets that have experienced an early episode of impact bombardment given how planets form. [ABSTRACT FROM AUTHOR]

The pursuit of understanding the origins of life (OoL) on and off Earth and the search for extraterrestrial life (ET) are central aspects of astrobiology. Despite the considerable efforts in both areas, more novel and multifaceted approaches are needed to address these profound questions with greater detail and with certainty. The complexity of the chemical milieu within ancient geological environments presents a diverse landscape where biomolecules and non-biomolecules interact. This interaction could lead to life as we know it, dominated by biomolecules, or to alternative forms of life where non-biomolecules could play a pivotal role. Such alternative forms of life could be found beyond Earth, i.e., on exoplanets and the moons of Jupiter and Saturn. Challenging the notion that all life, including ET life, must use the same building blocks as life on Earth, the concept of contingency—when expanded beyond its macroevolution interpretation—suggests that non-biomolecules may have played essential roles at the OoL. Here, we review the possible role of contingency and non-biomolecules at the OoL and synthesize a conceptual model formally linking contingency with non-biomolecular OoL theories. This model emphasizes the significance of considering the role of non-biomolecules both at the OoL on Earth or beyond, as well as their potential as agnostic biosignatures indicative of ET Life. [ABSTRACT FROM AUTHOR]

Assembly Theory provides a promising framework to explain the complexity of systems such as molecular structures and the origins of life, with broad applicability across various disciplines. In this study, we explore and consolidate different aspects of Assembly Theory by introducing a simplified Toy Model to simulate the autocatalytic formation of complex structures. This model abstracts the molecular formation process, focusing on the probabilistic control of catalysis rather than the intricate interactions found in organic chemistry. We establish a connection between probabilistic catalysis events and key principles of Assembly Theory, particularly the probability of a possible construction path in the formation of a complex object, and examine how the assembly of complex objects is impacted by the presence of autocatalysis. Our findings suggest that this presence of autocatalysis tends to favor longer consecutive construction sequences in environments with a low probability of catalysis, while this bias diminishes in environments with higher catalysis probabilities, highlighting the significant influence of environmental factors on the assembly of complex structures. [ABSTRACT FROM AUTHOR]

The definition, origin and recreation of life remain elusive. As others have suggested, only once we put life into reductionist physical terms will we be able to solve those questions. To that end, this work proposes the phenomenon of life to be the product of two dissipative mechanisms. From them, one characterises extant biological life and deduces a testable scenario for its origin. The proposed theory of life allows its replication, reinterprets ecological evolution and creates new constraints on the search for life. [ABSTRACT FROM AUTHOR]

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The three 31 nucleotide minihelix tRNA evolution theorem describes the evolution of type I and type II tRNAs to the last nucleotide. In databases, type I and type II tRNA V loops (V for variable) were improperly aligned, but alignment based on the theorem is accurate. Type II tRNA V arms were a 3′-acceptor stem (initially CCGCCGC) ligated to a 5′-acceptor stem (initially GCGGCGG). The type II V arm evolved to form a stem–loop–stem. In Archaea, tRNALeu and tRNASer are type II. In Bacteria, tRNALeu, tRNASer, and tRNATyr are type II. The trajectory of the type II V arm is determined by the number of unpaired bases just 5′ of the Levitt base (Vmax). For Archaea, tRNALeu has two unpaired bases, and tRNASer has one unpaired base. For Bacteria, tRNATyr has two unpaired bases, tRNALeu has one unpaired base, and tRNASer has zero unpaired bases. Thus, the number of synonymous type II tRNA sets is limited by the possible trajectory set points of the arm. From the analysis of aminoacyl-tRNA synthetase structures, contacts to type II V arms appear to adjust allosteric tension communicated primarily via tRNA to aminoacylating and editing active sites. To enhance allostery, it appears that type II V arm end loop contacts may tend to evolve to V arm stem contacts. [ABSTRACT FROM AUTHOR]

The origin of life is associated with the existing environmental factors of the Precambrian Era of the Earth. The minerals rich in sodium silicates, in aluminum and in other chemical elements, such as kaolinite, were among the factors present at that time. Kaolinite is an abundant mineral on our planet, which indicates that it possibly had an essential role in the origin of the first blocks that constructed life on Earth. Evidence of this is the cherts, which are rocks with a high concentration of silica that retain the vestiges of the most ancient life on our planet. There are also inorganic structures called biomorphs that are like the cherts of the Precambrian, which take on a morphology and crystalline structure depending on the chemical molecules that make up the reaction mixture. To evaluate the interaction of kaolinite with DNA, the objective of this work is to synthesize biomorphs in the presence of kaolinite and genomic DNA that comes from a prokaryote and a eukaryote microorganism. Our results show that the difference between the prokaryote DNA and the eukaryote DNA favors the morphology and the crystalline phase of the calcium silica–carbonate biomorphs, while in the case of the barium silica–carbonate biomorphs, the environmental factors participate directly in the morphology but not in the crystalline phase. Results show that when a mineral such as kaolinite is present in genomic DNA, it is precisely the DNA that controls both the morphology and the crystalline phase as well as the chemical composition of the structure. This fact is relevant as it shows that, independently of the morphology or the of size of the organism, it is the genomic DNA that controls all the chemical elements toward the most stable structure, therefore allowing the perpetuation, conservation and maintenance of life on our planet (since the origin of the genomic DNA in the Precambrian Era to the present day). [ABSTRACT FROM AUTHOR]

External flows of energy, entropy, and matter can cause sudden transitions in the stability of biological and industrial systems, fundamentally altering their dynamical function. How might we control and design these transitions in chemical reaction networks? Here, we analyze transitions giving rise to complex behavior in random reaction networks subject to external driving forces. In the absence of driving, we characterize the uniqueness of the steady state and identify the percolation of a giant connected component in these networks as the number of reactions increases. When subject to chemical driving (influx and outflux of chemical species), the steady state can undergo bifurcations, leading to multistability or oscillatory dynamics. By quantifying the prevalence of these bifurcations, we show how chemical driving and network sparsity tend to promote the emergence of these complex dynamics and increased rates of entropy production. We show that catalysis also plays an important role in the emergence of complexity, strongly correlating with the prevalence of bifurcations. Our results suggest that coupling a minimal number of chemical signatures with external driving can lead to features present in biochemical processes and abiogenesis. [ABSTRACT FROM AUTHOR]

Abstract Thioamide bonds are important intermediates in prebiotic chemistry. In cyanosulfidic prebiotic chemistry, they serve as crucial intermediates in the pathways that lead to the formation of many important biomolecules (e.g., amino acids). They can also serve as purine and pyrimidine precursors, the two classes of heterocycle employed in genetic molecules. Despite their importance, the formation of thioamide bonds from nitriles under prebiotic conditions has required large excesses of sulfide or compounds with unknown prebiotic sources. Here, we describe the thiol-catalyzed formation of thioamide bonds from nitriles. We show that the formation of the simplest of these compounds, thioformamide, forms readily in spark-discharge experiments from hydrogen cyanide, sulfide, and a methanethiol catalyst, suggesting potential accumulation on early Earth. Lastly, we demonstrate that thioformamide has a Gibbs energy of hydrolysis ( $$\Delta G^{\circ }_r$$ Δ G r ∘ ) comparable to other energy-currencies on early Earth such as pyrophosphate and thioester bonds. Overall, our findings imply that thioamides might have been abundant on early Earth and served a variety of functions during chemical evolution.

The origin of life is associated with the existing environmental factors of the Precambrian Era of the Earth. The minerals rich in sodium silicates, in aluminum and in other chemical elements, such as kaolinite, were among the factors present at that time. Kaolinite is an abundant mineral on our planet, which indicates that it possibly had an essential role in the origin of the first blocks that constructed life on Earth. Evidence of this is the cherts, which are rocks with a high concentration of silica that retain the vestiges of the most ancient life on our planet. There are also inorganic structures called biomorphs that are like the cherts of the Precambrian, which take on a morphology and crystalline structure depending on the chemical molecules that make up the reaction mixture. To evaluate the interaction of kaolinite with DNA, the objective of this work is to synthesize biomorphs in the presence of kaolinite and genomic DNA that comes from a prokaryote and a eukaryote microorganism. Our results show that the difference between the prokaryote DNA and the eukaryote DNA favors the morphology and the crystalline phase of the calcium silica–carbonate biomorphs, while in the case of the barium silica–carbonate biomorphs, the environmental factors participate directly in the morphology but not in the crystalline phase. Results show that when a mineral such as kaolinite is present in genomic DNA, it is precisely the DNA that controls both the morphology and the crystalline phase as well as the chemical composition of the structure. This fact is relevant as it shows that, independently of the morphology or the of size of the organism, it is the genomic DNA that controls all the chemical elements toward the most stable structure, therefore allowing the perpetuation, conservation and maintenance of life on our planet (since the origin of the genomic DNA in the Precambrian Era to the present day).

Background: Carbon monoxide (CO), hypothetically linked to prebiotic biosynthesis and possibly the origin of the life, emerges as a substantive growth substrate for numerous microorganisms. In anoxic environments, the coupling of CO oxidation with hydrogen (H2) production is an essential source of electrons, which can subsequently be utilized by hydrogenotrophic bacteria (e.g., organohalide-respring bacteria). While Dehalococcoides strains assume pivotal roles in the natural turnover of halogenated organics and the bioremediation of chlorinated ethenes, relying on external H2 as their electron donor and acetate as their carbon source, the synergistic dynamics within the anaerobic microbiome have received comparatively less scrutiny. This study delves into the intriguing prospect of CO serving as both the exclusive carbon source and electron donor, thereby supporting the reductive dechlorination of trichloroethene (TCE). Results: The metabolic pathway involved anaerobic CO oxidation, specifically the Wood-Ljungdahl pathway, which produced H2 and acetate as primary metabolic products. In an intricate microbial interplay, these H2 and acetate were subsequently utilized by Dehalococcoides, facilitating the dechlorination of TCE. Notably, Acetobacterium emerged as one of the pivotal collaborators for Dehalococcoides, furnishing not only a crucial carbon source essential for its growth and proliferation but also providing a defense against CO inhibition. Conclusions: This research expands our understanding of CO's versatility as a microbial energy and carbon source and unveils the intricate syntrophic dynamics underlying reductive dechlorination. 3ez2V3iuLHAKAp3AxS5o4q Video Abstract [ABSTRACT FROM AUTHOR]

The ability of living organisms to persist, grow, evolve and invade environments seemingly challenges physical laws. Emerging Autonomous Systems representing autocatalytic cycles constituted of energized components in a state of Dynamic Kinetic Stability feature some of these properties. These simple theoretical models can grow, can be transferred but need an initiation to emerge and can collapse. Moreover, they can undergo kinetic selection in a way consistent with Darwinian behaviour, though they lack the ability to undergo change. The mere existence of these systems and their open‐ended growth potential are proposed to constitute a transmissible factor of a non‐coded kind. The onset and selection of epigenetic factors may therefore have preceded that of genetic polymers. Here is addressed the question of how these systems may arise from the diversity exhibited by abiotic organic matter, sometimes associated with intractable mixtures, which may actually be useful in providing initiators. The Darwinian description of evolution may therefore be merged without critical discontinuity within an origin scenario. Accordingly, such a theory would rests solely on physicochemical laws beginning with the potential of emerging autonomous systems to compete and invade the space dimension, and to further develop along other available dimensions including variability and, possibly, cognition. [ABSTRACT FROM AUTHOR]

To test the hypothesis that an abiotic Earth and its inert atmosphere could form chemically reactive carbon-and nitrogen-containing compounds, we designed a plasma electrochemical setup to mimic lightning-induced electrochemistry under steady-state conditions of the early Earth. Air-gap electrochemical reactions at air-water-ground interfaces lead to remarkable yields, with up to 40 moles of carbon dioxide being reduced into carbon monoxide and formic acid, and 3 moles of gaseous nitrogen being fixed into nitrate, nitrite, and ammonium ions, per mole of transmitted electrons. Interfaces enable reactants (e.g., minerals) that may have been on land, in lakes, and in oceans to participate in radical and redox reactions, leading to higher yields compared to gas-phase-only reactions. Cloud-to-ground lightning strikes could have generated high concentrations of reactive molecules locally, establishing diverse feedstocks for early life to emerge and survive globally. [ABSTRACT FROM AUTHOR]

Thioamide bonds are important intermediates in prebiotic chemistry. In cyanosulfidic prebiotic chemistry, they serve as crucial intermediates in the pathways that lead to the formation of many important biomolecules (e.g., amino acids). They can also serve as purine and pyrimidine precursors, the two classes of heterocycle employed in genetic molecules. Despite their importance, the formation of thioamide bonds from nitriles under prebiotic conditions has required large excesses of sulfide or compounds with unknown prebiotic sources. Here, we describe the thiol-catalyzed formation of thioamide bonds from nitriles. We show that the formation of the simplest of these compounds, thioformamide, forms readily in spark-discharge experiments from hydrogen cyanide, sulfide, and a methanethiol catalyst, suggesting potential accumulation on early Earth. Lastly, we demonstrate that thioformamide has a Gibbs energy of hydrolysis ( Δ G r ∘ ) comparable to other energy-currencies on early Earth such as pyrophosphate and thioester bonds. Overall, our findings imply that thioamides might have been abundant on early Earth and served a variety of functions during chemical evolution. [ABSTRACT FROM AUTHOR]

Amino acids are essential for Earth-like life and are hypothesised to have originated in interstellar space, potentially being transported to Earth via meteorite impacts. Detecting amino acids in interstellar environments and understanding their formation mechanisms through laboratory experiments are crucial for supporting this hypothesis and unravelling the origins of life. In this study, the formation of serine ( $ {\rm NH}_2{\rm CH}({\rm CH}_2{\rm OH}){\rm COOH}) $ NH 2 CH (CH 2 OH) COOH) from α-glycyl ( $ {\rm NH}_2{\rm C}{\cdot }{\rm HCOOH} $ NH 2 C ⋅ HCOOH ) and hydroxymethyl ( $ {\cdot } {\rm CH}_2{\rm OH} $ ⋅ CH 2 OH ) radicals was investigated using quantum chemical computations. It was found that the anticipated recombination reaction, along with analogous formation pathways of other natural amino acids, is accompanied by competing reactions yielding alternative products, potentially diminishing serine formation. Alternative interstellar formation pathways for serine are proposed, which could be experimentally tested by future laboratory studies. [ABSTRACT FROM AUTHOR]

The emergence of life from nonlife, or abiogenesis, remains a fundamental question in scientific inquiry. In this article, we investigate the probability of the origin of life (per conducive site) by leveraging insights from Earth's environments. If life originated endogenously on Earth, its existence is indeed endowed with informative value, although the interpretation of the attendant significance hinges critically upon prior assumptions. By adopting a Bayesian framework, for an agnostic prior, we establish a direct connection between the number of potential locations for abiogenesis on Earth and the probability of life's emergence per site. Our findings suggest that constraints on the availability of suitable environments for the origin(s) of life on Earth may offer valuable insights into the probability of abiogenesis and the frequency of life in the universe. [ABSTRACT FROM AUTHOR]

The core autocatalytic cycle of the formose reaction may be enhanced or eroded by the presence of simple molecules at life's origin. Utilizing quantum chemistry, we calculate the thermodynamics and kinetics of reactions both within the core cycle and those that deplete the reactants and intermediates, such as the Cannizzaro reaction. We find that via disproportionation of aldehydes into carboxylic acids and alcohols, the Cannizzaro reaction furnishes simple catalysts for a variety of reactions. We also find that ammonia can catalyze both in-cycle and Cannizzaro reactions while hydrogen sulfide does not; both, however, play a role in sequestering reactants and intermediates in the web of potential reactions. [ABSTRACT FROM AUTHOR]

Detecting biosignatures of life in extraterrestrial environments remains one of the primary objectives of scientific inquiry. Currently, both remote and direct detection methods are primarily aimed at identifying key molecular classes fundamental to terrestrial biology. However, a more universally applicable spectroscopic approach could involve searching for homochiral molecules. Thus, this perspective delves into the significance of homochirality as a critical factor in the origin of life. Without homochirality, the formation of self‐recognizing and self‐replicating complex molecules would be hindered. The various hypotheses concerning the origin of homochiral molecules have been explored and analyzed within this context. This perspective emphasizes the potential for discovering extraterrestrial microscopic life through the detection of homochiral molecules using chirodetecting methods such as chromatography and chiroptical spectroscopy or circular polarimetry as a promising remote technique. This discussion highlights the importance of homochirality in the broader search for life beyond Earth and underscores the need for innovative methodologies and instrumentation in astrobiological research. These techniques can be an effective method for detecting homochirality on future planetary missions. [ABSTRACT FROM AUTHOR]

Low-energy cosmic rays (LECRs) play a crucial role in the formation of planetary systems, and detecting and reconstructing the properties of early LECRs is essential for understanding the mechanisms of planetary system formation. Given that LECRs interact with the surrounding medium to produce nuclear de-excitation line emissions, which are gamma-ray emissions with energy mainly within 0.1–10 MeV and are unaffected by stellar wind modulation, these emissions can accurately reflect the properties of LECRs. This study introduces an innovative method for using gamma-ray emissions to infer LECR properties. We employed the Parker transport equation to simulate the propagation and spectral evolution of LECRs in a protoplanetary disk and calculated the characteristic gamma-ray emissions resulting from interactions between LECRs and disk material. These gamma-ray emissions encapsulate the spectral information of LECRs, providing a powerful tool to reconstruct the cosmic ray environment at that time. This method, supported by further theoretical developments and observations, will fundamentally enhance our understanding of the impact of CRs on the origin and evolution of planetary systems and address significant scientific questions regarding the cosmic ray environment at the origin of life. [ABSTRACT FROM AUTHOR]

Natural selection has a formal definition as the natural process that results in the survival and reproductive success of individuals or groups best adjusted to their environment, leading to the perpetuation of those genetic qualities best suited to that organism's environmental niche. Within conventional Neo-Darwinism, the largest source of those variations that can be selected is presumed to be secondary to random genetic mutations. As these arise, natural selection sustains adaptive traits in the context of a 'struggle for existence'. Consequently, in the 20th century, natural selection was generally portrayed as the primary evolutionary driver. The 21st century offers a comprehensive alternative to Neo-Darwinian dogma within Cognition-Based Evolution. The substantial differences between these respective evolutionary frameworks have been most recently articulated in a revision of Crick's Central Dogma, a former centerpiece of Neo-Darwinism. The argument is now advanced that the concept of natural selection should also be comprehensively reappraised. Cognitive selection is presented as a more precise term better suited to 21st century biology. Since cognition began with life's origin, natural selection represents cognitive selection. [ABSTRACT FROM AUTHOR]

We hypothesize that the first ancestral "protocell" molecular structures, i.e., the first RNAs and peptides that gradually transformed into real cells once the Earth had cooled sufficiently for organic molecules to appear, have left traces in the RNAs and the genes in present cells. We propose a circular RNA that could have been one of these ancestral structures whose vestigial pentameric subsequences would mark the evolution from this key moment when the protocells began to join with living organisms. In particular, we propose that, in present RNAs (ribosomal or messenger), which play an important role in the metabolism of current cells, we look for traces of the proposed primitive structure in the form of pentamers (or longer fragments) that belong to their nucleotide sequence. The result obtained can be summarized in the existence of a gradient of occurrence of such pentamers, with a high frequency for the most vital functions (protein synthesis, nucleic synthesis, cell respiration, etc.). This gradient is also visible between organisms, from the oldest (Archaea) to the most recent (Eukaryotes) in the evolution of species. [ABSTRACT FROM AUTHOR]

Urea is believed to have been essential to the synthesis of prebiotic nucleotides and thereby the RNA or DNA of the first lifeforms. Models suggesting that life began in wet‐dry cycles around shallow aquatic ponds imply that reactants such as urea were exposed to deep ultraviolet irradiation from the young sun. Detrimental photodissociation of urea induced by deep UV excitation potentially challenges these models. We here follow the primary deep ultraviolet photochemistry of aqueous urea. The data show that urea is barely excited at 200 nm due to weak ultraviolet absorption. The likelihood of photodissociation is further reduced by strong intra‐molecular coupling of the CN and CO stretch vibrations accompanied by an efficient dissipation of the excitation energy to the surrounding water molecules mitigated by urea‐water hydrogen bonds. We find that 54±5 % of the excited urea molecules dissociate. Reactions between the photoproducts and surrounding solvent molecules form carbamic acid or the carbamate anions within 0.6 ps. The molecules that do not dissociate return to the electronic ground state in 2 ps. Interestingly, the photodissociation processes of urea in the aqueous phase is different from earlier reported reactions observed following the VUV photolysis of urea in noble gas matrices and highlight the potential influence of water on the prebiotic photochemistry. [ABSTRACT FROM AUTHOR]

Resolving a robust phylogeny of an organismal group is often hindered by the limited availability of samples suitable for genomic or transcriptomic sequencing. Even for lineages of notable importance in evolutionary ecology, our phylogenetic comprehension remains largely unsatisfactory due to the challenges of acquiring samples across the clade. The long‐horned beetle genus Anoplophora Hope exemplifies such a group, globally renowned for two invasive pests—the Asian long‐horned beetle and citrus long‐horned beetle—which have inflicted significant damage to deciduous hardwood forest in North America and Europe. In contrast to the two temperate pests, the remaining 50 species in the genus inhabit subtropical forests of Southeast Asia, where most species are only infrequently encountered. Here, we present the first comprehensive phylogeny of Anoplophora using a PCR‐based target enrichment museomics approach. As a case study of employing PCR‐generated custom probes, we demonstrate the robustness and cost‐effectiveness of this in‐house method in successfully acquiring sequence data from historical specimens. Through extensive sampling of Anoplophora using museum specimens, we reveal a non‐sister relationship between the two temperate species and provide evidence for addressing taxonomic conundrums. Our biogeographical analyses indicate that the adaptation of the two temperate species occurred independently during the late Pliocene and Pleistocene after the establishment of temperate forests in East Asia in the late Miocene. Our findings highlight the importance of comprehensive phylogenetic inference in understanding the patterns and processes of these beetles' adaptation to temperate forests and lay the groundwork for investigating the genetic mechanism underlying life in the cold. [ABSTRACT FROM AUTHOR]

At the origin, the emergence of proteins was based on crucial prebiotic stages in which simple amino acids‐based building blocks spontaneously evolved from the prebiotic soup into random proto‐polymers called protoproteins. Despite advances in modern peptide synthesis, these prebiotic chemical routes to protoproteins remain puzzling. We discuss in this perspective how polymer science and systems chemistry are reaching a point of convergence in which simple monomers called N‐carboxyanhydrides would be able to form such protoproteins via the emergence of a protometabolic cycle involving aqueous polymerization and featuring macromolecular Darwinism behavior. [ABSTRACT FROM AUTHOR]