Artigos de revistas: "Prebiotic catalysis"

1

Ferris, J. P. "Catalysis and Prebiotic Synthesis". Reviews in Mineralogy and Geochemistry 59, n.º 1 (1 de janeiro de 2005): 187–210. http://dx.doi.org/10.2138/rmg.2005.59.8.

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Ferris, James P. "Catalysis and prebiotic RNA synthesis". Origins of Life and Evolution of the Biosphere 23, n.º 5-6 (dezembro de 1993): 307–15. http://dx.doi.org/10.1007/bf01582081.

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Jheeta, Sohan, e Prakash Joshi. "Prebiotic RNA Synthesis by Montmorillonite Catalysis". Life 4, n.º 3 (5 de agosto de 2014): 318–30. http://dx.doi.org/10.3390/life4030318.

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Le Vay, Kristian, Elia Salibi, Emilie Y. Song e Hannes Mutschler. "Nucleic Acid Catalysis under Potential Prebiotic Conditions". Chemistry – An Asian Journal 15, n.º 2 (9 de dezembro de 2019): 214–30. http://dx.doi.org/10.1002/asia.201901205.

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Tsanakopoulou, Maria, e John D. Sutherland. "Cyanamide as a prebiotic phosphate activating agent – catalysis by simple 2-oxoacid salts". Chemical Communications 53, n.º 87 (2017): 11893–96. http://dx.doi.org/10.1039/c7cc07517k.

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De Graaf, R. M., J. Visscher, Y. Xu, G. Arrhenius e Alan W. Schwartz. "Mineral Catalysis of a Potentially Prebiotic Aldol Condensation". Journal of Molecular Evolution 47, n.º 5 (novembro de 1998): 501–7. http://dx.doi.org/10.1007/pl00006406.

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Maurel, Marie-Christine, e Jacques Ninio. "Catalysis by a prebiotic nucleotide analog of histidine". Biochimie 69, n.º 5 (maio de 1987): 551–53. http://dx.doi.org/10.1016/0300-9084(87)90094-0.

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Ninio, Jacques. "Errors and Alternatives in Prebiotic Replication and Catalysis". Chemistry & Biodiversity 4, n.º 4 (abril de 2007): 622–32. http://dx.doi.org/10.1002/cbdv.200790054.

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Vallée, Yannick, e Sparta Youssef-Saliba. "Sulfur Amino Acids: From Prebiotic Chemistry to Biology and Vice Versa". Synthesis 53, n.º 16 (1 de abril de 2021): 2798–808. http://dx.doi.org/10.1055/a-1472-7914.

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AbstractTwo sulfur-containing amino acids are included in the list of the 20 classical protein amino acids. A methionine residue is introduced at the start of the synthesis of all current proteins. Cysteine, thanks to its thiol function, plays an essential role in a very large number of catalytic sites. Here we present what is known about the prebiotic synthesis of these two amino acids and homocysteine, and we discuss their introduction into primitive peptides and more elaborate proteins.1 Introduction2 Sulfur Sources3 Prebiotic Synthesis of Cysteine4 Prebiotic Synthesis of Methionine5 Homocysteine and Its Thiolactone6 Methionine and Cystine in Proteins7 Prebiotic Scenarios Using Sulfur Amino Acids8 Introduction of Cys and Met in the Genetic Code9 Conclusion

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Navrotsky, Alexandra, Richard Hervig, James Lyons, Dong-Kyun Seo, Everett Shock e Albert Voskanyan. "Cooperative formation of porous silica and peptides on the prebiotic Earth". Proceedings of the National Academy of Sciences 118, n.º 2 (29 de dezembro de 2020): e2021117118. http://dx.doi.org/10.1073/pnas.2021117118.

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Modern technology has perfected the synthesis of catalysts such as zeolites and mesoporous silicas using organic structure directing agents (SDA) and their industrial use to catalyze a large variety of organic reactions within their pores. We suggest that early in prebiotic evolution, synergistic interplay arose between organic species in aqueous solution and silica formed from rocks by dynamic dissolution–recrystallization. The natural organics, for example, amino acids, small peptides, and fatty acids, acted as SDA for assembly of functional porous silica structures that induced further polymerization of amino acids and peptides, as well as other organic reactions. Positive feedback between synthesis and catalysis in the silica–organic system may have accelerated the early stages of abiotic evolution by increasing the formation of polymerized species.

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Gull, Maheen, e Matthew A. Pasek. "The Role of Glycerol and Its Derivatives in the Biochemistry of Living Organisms, and Their Prebiotic Origin and Significance in the Evolution of Life". Catalysts 11, n.º 1 (10 de janeiro de 2021): 86. http://dx.doi.org/10.3390/catal11010086.

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The emergence and evolution of prebiotic biomolecules on the early Earth remain a question that is considered crucial to understanding the chemistry of the origin of life. Amongst prebiotic molecules, glycerol is significant due to its ubiquity in biochemistry. In this review, we discuss the significance of glycerol and its various derivatives in biochemistry, their plausible roles in the origin and evolution of early cell membranes, and significance in the biochemistry of extremophiles, followed by their prebiotic origin on the early Earth and associated catalytic processes that led to the origin of these compounds. We also discuss various scenarios for the prebiotic syntheses of glycerol and its derivates and evaluate these to determine their relevance to early Earth biochemistry and geochemistry, and recapitulate the utilization of various minerals (including clays), condensation agents, and solvents that could have led to the successful prebiotic genesis of these biomolecules. Furthermore, important prebiotic events such as meteoritic delivery and prebiotic synthesis reactions under astrophysical conditions are also discussed. Finally, we have also highlighted some novel features of glycerol, including glycerol nucleic acid (GNA), in the origin and evolution of the life.

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Gull, Maheen, e Matthew A. Pasek. "The Role of Glycerol and Its Derivatives in the Biochemistry of Living Organisms, and Their Prebiotic Origin and Significance in the Evolution of Life". Catalysts 11, n.º 1 (10 de janeiro de 2021): 86. http://dx.doi.org/10.3390/catal11010086.

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The emergence and evolution of prebiotic biomolecules on the early Earth remain a question that is considered crucial to understanding the chemistry of the origin of life. Amongst prebiotic molecules, glycerol is significant due to its ubiquity in biochemistry. In this review, we discuss the significance of glycerol and its various derivatives in biochemistry, their plausible roles in the origin and evolution of early cell membranes, and significance in the biochemistry of extremophiles, followed by their prebiotic origin on the early Earth and associated catalytic processes that led to the origin of these compounds. We also discuss various scenarios for the prebiotic syntheses of glycerol and its derivates and evaluate these to determine their relevance to early Earth biochemistry and geochemistry, and recapitulate the utilization of various minerals (including clays), condensation agents, and solvents that could have led to the successful prebiotic genesis of these biomolecules. Furthermore, important prebiotic events such as meteoritic delivery and prebiotic synthesis reactions under astrophysical conditions are also discussed. Finally, we have also highlighted some novel features of glycerol, including glycerol nucleic acid (GNA), in the origin and evolution of the life.

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Yang, Jiangang, Shangshang Sun, Yan Men, Yan Zeng, Yueming Zhu, Yuanxia Sun e Yanhe Ma. "Transformation of formaldehyde into functional sugars via multi-enzyme stepwise cascade catalysis". Catalysis Science & Technology 7, n.º 16 (2017): 3459–63. http://dx.doi.org/10.1039/c7cy01062a.

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Cornell, Caitlin E., Roy A. Black, Mengjun Xue, Helen E. Litz, Andrew Ramsay, Moshe Gordon, Alexander Mileant et al. "Prebiotic amino acids bind to and stabilize prebiotic fatty acid membranes". Proceedings of the National Academy of Sciences 116, n.º 35 (12 de agosto de 2019): 17239–44. http://dx.doi.org/10.1073/pnas.1900275116.

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The membranes of the first protocells on the early Earth were likely self-assembled from fatty acids. A major challenge in understanding how protocells could have arisen and withstood changes in their environment is that fatty acid membranes are unstable in solutions containing high concentrations of salt (such as would have been prevalent in early oceans) or divalent cations (which would have been required for RNA catalysis). To test whether the inclusion of amino acids addresses this problem, we coupled direct techniques of cryoelectron microscopy and fluorescence microscopy with techniques of NMR spectroscopy, centrifuge filtration assays, and turbidity measurements. We find that a set of unmodified, prebiotic amino acids binds to prebiotic fatty acid membranes and that a subset stabilizes membranes in the presence of salt and Mg2+. Furthermore, we find that final concentrations of the amino acids need not be high to cause these effects; membrane stabilization persists after dilution as would have occurred during the rehydration of dried or partially dried pools. In addition to providing a means to stabilize protocell membranes, our results address the challenge of explaining how proteins could have become colocalized with membranes. Amino acids are the building blocks of proteins, and our results are consistent with a positive feedback loop in which amino acids bound to self-assembled fatty acid membranes, resulting in membrane stabilization and leading to more binding in turn. High local concentrations of molecular building blocks at the surface of fatty acid membranes may have aided the eventual formation of proteins.

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Stolar, Tomislav, Saša Grubešić, Nikola Cindro, Ernest Meštrović, Krunoslav Užarević e José G. Hernández. "Mechanochemical Prebiotic Peptide Bond Formation**". Angewandte Chemie International Edition 60, n.º 23 (29 de abril de 2021): 12727–31. http://dx.doi.org/10.1002/anie.202100806.

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Shahi, Sahil Rajiv, e H. James Cleaves. "The Effects of Iron on In Silico Simulated Abiotic Reaction Networks". Molecules 27, n.º 24 (13 de dezembro de 2022): 8870. http://dx.doi.org/10.3390/molecules27248870.

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Iron is one of the most abundant elements in the Universe and Earth’s surfaces, and undergoes a redox change of approximately 0.77 mV in changing between its +2 and +3 states. Many contemporary terrestrial organisms are deeply connected to inorganic geochemistry via exploitation of this redox change, and iron redox reactions and catalysis are known to cause significant changes in the course of complex abiotic reactions. These observations point to the question of whether iron may have steered prebiotic chemistry during the emergence of life. Using kinetically naive in silico reaction modeling we explored the potential effects of iron ions on complex reaction networks of prebiotic interest, namely the formose reaction, the complexifying degradation reaction of pyruvic acid in water, glucose degradation, and the Maillard reaction. We find that iron ions produce significant changes in the connectivity of various known diversity-generating reaction networks of proposed prebiotic significance, generally significantly diversifying novel molecular products by ~20%, but also adding the potential for kinetic effects that could allow iron to steer prebiotic chemistry in marked ways.

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Alli, Sauliha R., Ilona Gorbovskaya, Jonathan C. W. Liu, Nathan J. Kolla, Lisa Brown e Daniel J. Müller. "The Gut Microbiome in Depression and Potential Benefit of Prebiotics, Probiotics and Synbiotics: A Systematic Review of Clinical Trials and Observational Studies". International Journal of Molecular Sciences 23, n.º 9 (19 de abril de 2022): 4494. http://dx.doi.org/10.3390/ijms23094494.

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An emerging body of literature demonstrates differences in the gut microbiome (GMB) of patients with major depressive disorder (MDD) compared to healthy controls (HC), as well as the potential benefits of prebiotic, probiotic, and synbiotic treatment. We conducted a systematic review of 24 observational studies (n = 2817), and 19 interventional trials (n = 1119). We assessed alpha diversity, beta diversity, and taxa abundance changes in patients with MDD relative to HC, as well as the effect of prebiotics, probiotics, and synbiotics on depressive symptoms in individuals with clinical or subclinical depression. We observed no significant differences in alpha diversity but a significant difference in beta diversity between patients with MDD and HC. There were fluctuations in the abundance of specific taxa in patients with MDD relative to HC. Probiotic and synbiotic, but not prebiotic, treatment showed a modest benefit in reducing depressive symptoms in patients with MDD over four to nine weeks. The GMB profiles of patients with MDD differ significantly from HC, but further studies are needed to elucidate the benefits of prebiotic, probiotic and synbiotic treatments relative to antidepressants and over longer follow-up before these therapies are implemented into clinical practice.

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Teichert, Jennifer S., Florian M. Kruse e Oliver Trapp. "Direct Prebiotic Pathway to DNA Nucleosides". Angewandte Chemie International Edition 58, n.º 29 (15 de julho de 2019): 9944–47. http://dx.doi.org/10.1002/anie.201903400.

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19

Megur, Ashwinipriyadarshini, Eric Banan-Mwine Daliri, Daiva Baltriukienė e Aurelijus Burokas. "Prebiotics as a Tool for the Prevention and Treatment of Obesity and Diabetes: Classification and Ability to Modulate the Gut Microbiota". International Journal of Molecular Sciences 23, n.º 11 (29 de maio de 2022): 6097. http://dx.doi.org/10.3390/ijms23116097.

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Diabetes and obesity are metabolic diseases that have become alarming conditions in recent decades. Their rate of increase is becoming a growing concern worldwide. Recent studies have established that the composition and dysfunction of the gut microbiota are associated with the development of diabetes. For this reason, strategies such as the use of prebiotics to improve intestinal microbial structure and function have become popular. Consumption of prebiotics for modulating the gut microbiota results in the production of microbial metabolites such as short-chain fatty acids that play essential roles in reducing blood glucose levels, mitigating insulin resistance, reducing inflammation, and promoting the secretion of glucagon-like peptide 1 in the host, and this accounts for the observed remission of metabolic diseases. Prebiotics can be either naturally extracted from non-digestible carbohydrate materials or synthetically produced. In this review, we discussed current findings on how the gut microbiota and microbial metabolites may influence host metabolism to promote health. We provided evidence from various studies that show the ability of prebiotic consumption to alter gut microbial profile, improve gut microbial metabolism and functions, and improve host physiology to alleviate diabetes and obesity. We conclude among other things that the application of systems biology coupled with bioinformatics could be essential in ascertaining the exact mechanisms behind the prebiotic–gut microbe–host interactions required for diabetes and obesity improvement.

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Yaman, Tolga, e Jeremy N. Harvey. "Computational Analysis of a Prebiotic Amino Acid Synthesis with Reference to Extant Codon–Amino Acid Relationships". Life 11, n.º 12 (4 de dezembro de 2021): 1343. http://dx.doi.org/10.3390/life11121343.

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Novel density functional theory calculations are presented regarding a mechanism for prebiotic amino acid synthesis from alpha-keto acids that was suggested to happen via catalysis by dinucleotide species. Our results were analysed with comparison to the original hypothesis (Copley et al., PNAS, 2005, 102, 4442–4447). It was shown that the keto acid–dinucleotide hypothesis for possible prebiotic amino acid synthesis was plausible based on an initial computational analysis, and details of the structures for the intermediates and transition states showed that there was wide scope for interactions between the keto acid and dinucleotide moieties that could affect the free energy profiles and lead to the required proto-metabolic selectivity.

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Matthews, Clifford N., e Robert D. Minard. "Hydrogen cyanide polymers connect cosmochemistry and biochemistry". Proceedings of the International Astronomical Union 4, S251 (fevereiro de 2008): 453–58. http://dx.doi.org/10.1017/s1743921308022175.

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AbstractTo understand the origin of protein/nucleic acid based life as we know it on Earth, we must “follow” the nitrogen. Because of its unique hydrogen bonding characteristics, nitrogen is the key element in catalytic and/or informational proteins and nucleic acids essential to cell function and reproduction. We present evidence that HCN is the original source of prebiotic protein and nucleobase nitrogen. We also present chemically rational models supporting the radical hypothesis that the polymerization of HCN yields ab initio mundi prebiotic protein and polynucleobase macromolecules of sufficient size and complexity to allow the spontaneous generation of pre-RNA World biopolymers capable of catalysis and information transfer.

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Kelly, David R., Alastair Meek e Stanley M. Roberts. "Chiral amplification by polypeptides and its relevance to prebiotic catalysis". Chemical Communications, n.º 18 (2004): 2021. http://dx.doi.org/10.1039/b404379k.

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Ferris, J. P. "Mineral Catalysis and Prebiotic Synthesis: Montmorillonite-Catalyzed Formation of RNA". Elements 1, n.º 3 (1 de junho de 2005): 145–49. http://dx.doi.org/10.2113/gselements.1.3.145.

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Harrison, Stuart A., William L. Webb, Hanadi Rammu e Nick Lane. "Prebiotic Synthesis of Aspartate Using Life’s Metabolism as a Guide". Life 13, n.º 5 (12 de maio de 2023): 1177. http://dx.doi.org/10.3390/life13051177.

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A protometabolic approach to the origins of life assumes that the conserved biochemistry of metabolism has direct continuity with prebiotic chemistry. One of the most important amino acids in modern biology is aspartic acid, serving as a nodal metabolite for the synthesis of many other essential biomolecules. Aspartate’s prebiotic synthesis is complicated by the instability of its precursor, oxaloacetate. In this paper, we show that the use of the biologically relevant cofactor pyridoxamine, supported by metal ion catalysis, is sufficiently fast to offset oxaloacetate’s degradation. Cu2+-catalysed transamination of oxaloacetate by pyridoxamine achieves around a 5% yield within 1 h, and can operate across a broad range of pH, temperature, and pressure. In addition, the synthesis of the downstream product β-alanine may also take place in the same reaction system at very low yields, directly mimicking an archaeal synthesis route. Amino group transfer supported by pyridoxal is shown to take place from aspartate to alanine, but the reverse reaction (alanine to aspartate) shows a poor yield. Overall, our results show that the nodal metabolite aspartate and related amino acids can indeed be synthesised via protometabolic pathways that foreshadow modern metabolism in the presence of the simple cofactor pyridoxamine and metal ions.

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Takats, Zoltan, Sergio C. Nanita e R. Graham Cooks. "Serine Octamer Reactions: Indicators of Prebiotic Relevance". Angewandte Chemie International Edition 42, n.º 30 (4 de agosto de 2003): 3521–23. http://dx.doi.org/10.1002/anie.200351210.

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Ferris, J. P., P. C. Joshi, K. J. Wang, S. Miyakawa e W. Huang. "Catalysis in prebiotic chemistry: application to the synthesis of RNA oligomers". Advances in Space Research 33, n.º 1 (janeiro de 2004): 100–105. http://dx.doi.org/10.1016/j.asr.2003.02.010.

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Wolk, Steven K., Wesley S. Mayfield, Amy D. Gelinas, David Astling, Jessica Guillot, Edward N. Brody, Nebojsa Janjic e Larry Gold. "Modified nucleotides may have enhanced early RNA catalysis". Proceedings of the National Academy of Sciences 117, n.º 15 (30 de março de 2020): 8236–42. http://dx.doi.org/10.1073/pnas.1809041117.

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The modern version of the RNA World Hypothesis begins with activated ribonucleotides condensing (nonenzymatically) to make RNA molecules, some of which possess (perhaps slight) catalytic activity. We propose that noncanonical ribonucleotides, which would have been inevitable under prebiotic conditions, might decrease the RNA length required to have useful catalytic function by allowing short RNAs to possess a more versatile collection of folded motifs. We argue that modified versions of the standard bases, some with features that resemble cofactors, could have facilitated that first moment in which early RNA molecules with catalytic capability began their evolutionary path toward self-replication.

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Srivatsan, S. G. "Modeling prebiotic catalysis with nucleic acid-like polymers and its implications for the proposed RNA world". Pure and Applied Chemistry 76, n.º 12 (1 de janeiro de 2004): 2085–99. http://dx.doi.org/10.1351/pac200476122085.

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The theory that RNA molecules played a pivotal role in the early evolution of life is now widely accepted. Studies related to this hypothetical “RNA world” include three major areas: the formation of precursors for the first RNA molecules, the polymerization process, and the potential of RNA to catalyze chemical and biochemical reactions. Several chemical and biochemical studies performed under simulated prebiotic conditions support the role of RNA as both genetic as well as catalytic material. However, owing to the lack of credible mechanism for de novo nucleic acid synthesis and the hydrolytic instability of RNA molecules, there has been some serious discussion of whether biopolymers that closely resembled nucleic acid preceded the “RNA world”. In this context, an overview of prebiotic chemistry, the role of mineral surface, and the significance of studies related to RNA-like polymers in the origin of life are presented here.

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Monnard, Pierre-Alain. "Taming Prebiotic Chemistry: The Role of Heterogeneous and Interfacial Catalysis in the Emergence of a Prebiotic Catalytic/Information Polymer System". Life 6, n.º 4 (4 de novembro de 2016): 40. http://dx.doi.org/10.3390/life6040040.

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Mason, Stephen F. "Prebiotic sources of biomolecular handedness". Chirality 3, n.º 4 (1991): 223–26. http://dx.doi.org/10.1002/chir.530030403.

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Preiner, Martina, Joana C. Xavier, Andrey do Nascimento Vieira, Karl Kleinermanns, John F. Allen e William F. Martin. "Catalysts, autocatalysis and the origin of metabolism". Interface Focus 9, n.º 6 (18 de outubro de 2019): 20190072. http://dx.doi.org/10.1098/rsfs.2019.0072.

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If life on Earth started out in geochemical environments like hydrothermal vents, then it started out from gasses like CO 2 , N 2 and H 2 . Anaerobic autotrophs still live from these gasses today, and they still inhabit the Earth's crust. In the search for connections between abiotic processes in ancient geological systems and biotic processes in biological systems, it becomes evident that chemical activation (catalysis) of these gasses and a constant source of energy are key. The H 2 –CO 2 redox reaction provides a constant source of energy and anabolic inputs, because the equilibrium lies on the side of reduced carbon compounds. Identifying geochemical catalysts that activate these gasses en route to nitrogenous organic compounds and small autocatalytic networks will be an important step towards understanding prebiotic chemistry that operates only on the basis of chemical energy, without input from solar radiation. So, if life arose in the dark depths of hydrothermal vents, then understanding reactions and catalysts that operate under such conditions is crucial for understanding origins.

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Carrea, Giacomo, Stefano Colonna, David R. Kelly, Antonio Lazcano, Gianluca Ottolina e Stanley M. Roberts. "Polyamino acids as synthetic enzymes: mechanism, applications and relevance to prebiotic catalysis". Trends in Biotechnology 23, n.º 10 (outubro de 2005): 507–13. http://dx.doi.org/10.1016/j.tibtech.2005.07.010.

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Wang, Qingpu, e Oliver Steinbock. "Materials Synthesis and Catalysis in Microfluidic Devices: Prebiotic Chemistry in Mineral Membranes". ChemCatChem 12, n.º 1 (29 de outubro de 2019): 63–74. http://dx.doi.org/10.1002/cctc.201901495.

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Buhaș, Mihaela Cristina, Rareș Candrea, Laura Ioana Gavrilaș, Doina Miere, Alexandru Tătaru, Andreea Boca e Adrian Cătinean. "Transforming Psoriasis Care: Probiotics and Prebiotics as Novel Therapeutic Approaches". International Journal of Molecular Sciences 24, n.º 13 (7 de julho de 2023): 11225. http://dx.doi.org/10.3390/ijms241311225.

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Psoriasis is a chronic inflammatory skin disease with autoimmune pathological characteristics. Recent research has found a link between psoriasis, inflammation, and gut microbiota dysbiosis, and that probiotics and prebiotics provide benefits to patients. This 12-week open-label, single-center clinical trial evaluated the efficacy of probiotics (Bacillus indicus (HU36), Bacillus subtilis (HU58), Bacillus coagulans (SC208), Bacillus licheniformis (SL307), and Bacillus clausii (SC109)) and precision prebiotics (fructooligosaccharides, xylooligosaccharides, and galactooligosaccharides) in patients with psoriasis receiving topical therapy, with an emphasis on potential metabolic, immunological, and gut microbiota changes. In total, 63 patients were evaluated, with the first 42 enrolled patients assigned to the intervention group and the next 21 assigned to the control group (2:1 ratio; non-randomized). There were between-group differences in several patient characteristics at baseline, including age, psoriasis severity (the incidence of severe psoriasis was greater in the intervention group than in the control group), the presence of nail psoriasis, and psoriatic arthritis, though it is not clear whether or how these differences may have affected the study findings. Patients with psoriasis receiving anti-psoriatic local therapy and probiotic and prebiotic supplementation performed better in measures of disease activity, including Psoriasis Area and Severity Index, Dermatology Life Quality Index, inflammatory markers, and skin thickness compared with those not receiving supplementation. Furthermore, in the 15/42 patients in the intervention group who received gut microbiota analysis, the gut microbiota changed favorably following 12 weeks of probiotic and prebiotic supplementation, with a shift towards an anti-inflammatory profile.

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Seitz, Christian, Thomas Geisberger, Alexander Richard West, Jessica Fertl, Wolfgang Eisenreich e Claudia Huber. "From Zero to Hero: The Cyanide-Free Formation of Amino Acids and Amides from Acetylene, Ammonia and Carbon Monoxide in Aqueous Environments in a Simulated Hadean Scenario". Life 14, n.º 6 (1 de junho de 2024): 719. http://dx.doi.org/10.3390/life14060719.

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Amino acids are one of the most important building blocks of life. During the biochemical process of translation, cells sequentially connect amino acids via amide bonds to synthesize proteins, using the genetic information in messenger RNA (mRNA) as a template. From a prebiotic perspective (i.e., without enzymatic catalysis), joining amino acids to peptides via amide bonds is difficult due to the highly endergonic nature of the condensation reaction. We show here that amides can be formed in reactions catalyzed by the transition metal sulfides from acetylene, carbon monoxide and ammonia under aqueous conditions. Some α- and β-amino acids were also formed under the same conditions, demonstrating an alternative cyanide-free path for the formation of amino acids in prebiotic environments. Experiments performed with stable isotope labeled precursors, like 15NH4Cl and 13C-acetylene, enabled the accurate mass spectroscopic identification of the products formed from the starting materials and their composition. Reactions catalyzed using the transition metal sulfides seem to offer a promising alternative pathway for the formation of amides and amino acids in prebiotic environments, bypassing the challenges posed by the highly endergonic condensation reaction. These findings shed light on the potential mechanisms by which the building blocks of life could have originated on early Earth.

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Duan, Feiyu, Renfei Zhao, Jingyi Yang, Min Xiao e Lili Lu. "Integrated Utilization of Dairy Whey in Probiotic β-Galactosidase Production and Enzymatic Synthesis of Galacto-Oligosaccharides". Catalysts 11, n.º 6 (22 de maio de 2021): 658. http://dx.doi.org/10.3390/catal11060658.

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This work established an integrated utilization of dairy whey in β-galactosidase production from Lactobacillus bulgaricus and prebiotics synthesis by the probiotic enzyme. A cost-effective whey-based medium was newly developed for culturing Lactobacillus bulgaricus to produce β-galactosidase. The medium was optimized through response surface methodology (RSM) involving a series of statistical designs, such as the Plackett–Burman design, steepest ascent experiment, and central composite design. Under the optimized medium, the β-galactosidase activity of L. bulgaricus reached 2034 U/L, which was twice that produced from the traditional MRS medium. The cells of L. bulgaricus harvested from the whey-based medium were subsequently treated with lysozyme. The resulting crude enzyme was used as an efficient catalyst, which catalyzed the synthesis of the prebiotic galacto-oligosaccharides (GOS) in a high yield of 44.7% by using whey (200 g/L) as the substrate. The sugar mixture was further purified by activated charcoal adsorption, thereby yielding a high-purity level of 77.6% GOS.

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Kapoor, Shobhna, Melanie Berghaus, Saba Suladze, Daniel Prumbaum, Sebastian Grobelny, Patrick Degen, Stefan Raunser e Roland Winter. "Prebiotic Cell Membranes that Survive Extreme Environmental Pressure Conditions". Angewandte Chemie International Edition 53, n.º 32 (20 de junho de 2014): 8397–401. http://dx.doi.org/10.1002/anie.201404254.

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Sturtz, Miranda, e Christopher House. "Metal Catalysis Acting on Nitriles in Early Earth Hydrothermal Systems". Life 13, n.º 7 (7 de julho de 2023): 1524. http://dx.doi.org/10.3390/life13071524.

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Hydrothermal systems are areas in which heated fluids and organic molecules rush through basaltic material rich in metals and minerals. By studying malononitrile and acetonitrile, we examine the effects of metal and mineral nanoparticles on nitrile compounds in anoxic, hydrothermal conditions representing a prebiotic environment of early Earth. Polymerization, reduction, cyclization, and a phenomenon colloquially known as ‘chemical gardening’ (structure building via reprecipitation of metal compounds or complexing with organics) are all potential outcomes with the addition of metals and minerals. Reduction occurs with the addition of rhodium (Rh) or iron (II) sulfide (FeS), with positive identification of ethanol and ethylamine forming from acetonitrile reduction. We find that polymerization and insoluble product formation were associated with oxide minerals, metallic nickel (Ni), and metallic cobalt (Co) acting as catalysts. Oxide minerals strongly promoted polymerization into insoluble, tar-like products of nitriles. FeS, iron-nickel alloy (FeNi), and rhodium are unique cases that appear to act as reagents by actively participating in chemical gardening without returning to their initial state. Further, FeS tentatively had a phase change into the mineral parabutlerite. This research aims to identify metals and metal minerals that could best serve nitrile catalysis and reactions on early Earth.

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Fuentes-Carreón, Claudio Alejandro, Jorge Armando Cruz-Castañeda, Eva Mateo-Martí e Alicia Negrón-Mendoza. "Stability of DL-Glyceraldehyde under Simulated Hydrothermal Conditions: Synthesis of Sugar-like Compounds in an Iron(III)-Oxide-Hydroxide-Rich Environment under Acidic Conditions". Life 12, n.º 11 (8 de novembro de 2022): 1818. http://dx.doi.org/10.3390/life12111818.

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Researchers have suggested that the condensation of low-molecular-weight aldehydes under basic conditions (e.g., pH > 11) is the prebiotic reaction responsible for the abiotic formation of carbohydrates. It has also been suggested that surface hydrothermal systems were ubiquitous during the early Archean period. Therefore, the catalysis of prebiotic carbohydrate synthesis by metallic oxide minerals under acidic conditions in these environments seems considerably more probable than the more widely hypothesized reaction routes. This study investigates the stability of DL-glyceraldehyde and its reaction products under the simulated conditions of an Archean surface hydrothermal system. The Hveradalur geothermal area in Iceland was selected as an analog of such a system. HPLC-ESIMS, UV–Vis spectroscopy, Raman spectroscopy and XPS spectroscopy were used to analyze the reaction products. In hot (323 K) and acidic (pH 2) solutions under the presence of suspended iron(III) oxide hydroxide powder, DL-glyceraldehyde readily decomposes into low-molecular-weight compounds and transforms into sugar-like molecules via condensation reactions.

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Sabater, Carlos, Inés Calvete-Torre, Lorena Ruiz e Abelardo Margolles. "Arabinoxylan and Pectin Metabolism in Crohn’s Disease Microbiota: An In Silico Study". International Journal of Molecular Sciences 23, n.º 13 (25 de junho de 2022): 7093. http://dx.doi.org/10.3390/ijms23137093.

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Inflammatory bowel disease is a chronic disorder including ulcerative colitis and Crohn’s disease (CD). Gut dysbiosis is often associated with CD, and metagenomics allows a better understanding of the microbial communities involved. The objective of this study was to reconstruct in silico carbohydrate metabolic capabilities from metagenome-assembled genomes (MAGs) obtained from healthy and CD individuals. This computational method was developed as a mean to aid rationally designed prebiotic interventions to rebalance CD dysbiosis, with a focus on metabolism of emergent prebiotics derived from arabinoxylan and pectin. Up to 1196 and 1577 MAGs were recovered from CD and healthy people, respectively. MAGs of Akkermansia muciniphila, Barnesiella viscericola DSM 18177 and Paraprevotella xylaniphila YIT 11841 showed a wide range of unique and specific enzymes acting on arabinoxylan and pectin. These glycosidases were also found in MAGs recovered from CD patients. Interestingly, these arabinoxylan and pectin degraders are predicted to exhibit metabolic interactions with other gut microbes reduced in CD. Thus, administration of arabinoxylan and pectin may ameliorate dysbiosis in CD by promoting species with key metabolic functions, capable of cross-feeding other beneficial species. These computational methods may be of special interest for the rational design of prebiotic ingredients targeting at CD.

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Spohner, Sebastian C., e Peter Czermak. "Enzymatic production of prebiotic fructo‐oligosteviol glycosides". Journal of Molecular Catalysis B: Enzymatic 131 (setembro de 2016): 79–84. http://dx.doi.org/10.1016/j.molcatb.2016.06.006.

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Colville, Ben W. F., e Matthew W. Powner. "Selective Prebiotic Synthesis of α‐Threofuranosyl Cytidine by Photochemical Anomerization". Angewandte Chemie International Edition 60, n.º 19 (26 de março de 2021): 10526–30. http://dx.doi.org/10.1002/anie.202101376.

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Cintas, Pedro. "Sublime Arguments: Rethinking the Generation of Homochirality under Prebiotic Conditions". Angewandte Chemie International Edition 47, n.º 16 (7 de abril de 2008): 2918–20. http://dx.doi.org/10.1002/anie.200705192.

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Pasek, Matthew A, Terence P Kee, David E Bryant, Alexander A Pavlov e Jonathan I Lunine. "Production of Potentially Prebiotic Condensed Phosphates by Phosphorus Redox Chemistry". Angewandte Chemie International Edition 47, n.º 41 (29 de setembro de 2008): 7918–20. http://dx.doi.org/10.1002/anie.200802145.

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He, Christine, Adriana Lozoya-Colinas, Isaac Gállego, Martha A. Grover e Nicholas V. Hud. "Solvent viscosity facilitates replication and ribozyme catalysis from an RNA duplex in a model prebiotic process". Nucleic Acids Research 47, n.º 13 (6 de junho de 2019): 6569–77. http://dx.doi.org/10.1093/nar/gkz496.

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Abstract The RNA World hypothesis posits that RNA was once responsible for genetic information storage and catalysis. However, a prebiotic mechanism has yet to be reported for the replication of duplex RNA that could have operated before the emergence of polymerase ribozymes. Previously, we showed that a viscous solvent enables information transfer from one strand of long RNA duplex templates, overcoming ‘the strand inhibition problem'. Here, we demonstrate that the same approach allows simultaneous information transfer from both strands of long duplex templates. An additional challenge for the RNA World is that structured RNAs (like those with catalytic activity) function poorly as templates in model prebiotic RNA synthesis reactions, raising the question of how a single sequence could serve as both a catalyst and as a replication template. Here, we show that a viscous solvent also facilitates the transition of a newly synthesized hammerhead ribozyme sequence from its inactive, duplex state to its active, folded state. These results demonstrate how fluctuating environmental conditions can allow a ribozyme sequence to alternate between acting as a template for replication and functioning as a catalyst, and illustrate the potential for temporally changing environments to enable molecular processes necessary for the origin of life.

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Fiore, Michele, e René Buchet. "Symmetry Breaking of Phospholipids". Symmetry 12, n.º 9 (10 de setembro de 2020): 1488. http://dx.doi.org/10.3390/sym12091488.

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Either stereo reactants or stereo catalysis from achiral or chiral molecules are a prerequisite to obtain pure enantiomeric lipid derivatives. We reviewed a few plausibly organic syntheses of phospholipids under prebiotic conditions with special attention paid to the starting materials as pro-chiral dihydroxyacetone and dihydroxyacetone phosphate (DHAP), which are the key molecules to break symmetry in phospholipids. The advantages of homochiral membranes compared to those of heterochiral membranes were analysed in terms of specific recognition, optimal functions of enzymes, membrane fluidity and topological packing. All biological membranes contain enantiomerically pure lipids in modern bacteria, eukarya and archaea. The contemporary archaea, comprising of methanogens, halobacteria and thermoacidophiles, are living under extreme conditions reminiscent of primitive environment and may indicate the origin of one ancient evolution path of lipid biosynthesis. The analysis of the known lipid metabolism reveals that all modern cells including archaea synthetize enantiomerically pure lipid precursors from prochiral DHAP. Sn-glycerol-1-phosphate dehydrogenase (G1PDH), usually found in archaea, catalyses the formation of sn-glycerol-1-phosphate (G1P), while sn-glycerol-3-phosphate dehydrogenase (G3PDH) catalyses the formation of sn-glycerol-3-phosphate (G3P) in bacteria and eukarya. The selective enzymatic activity seems to be the main strategy that evolution retained to obtain enantiomerically pure lipids. The occurrence of two genes encoding for G1PDH and G3PDH served to build up an evolutionary tree being the basis of our hypothesis article focusing on the evolution of these two genes. Gene encoding for G3PDH in eukarya may originate from G3PDH gene found in rare archaea indicating that archaea appeared earlier in the evolutionary tree than eukarya. Archaea and bacteria evolved probably separately, due to their distinct respective genes coding for G1PDH and G3PDH. We propose that prochiral DHAP is an essential molecule since it provides a convergent link between G1DPH and G3PDH. The synthesis of enantiopure phospholipids from DHAP appeared probably firstly in the presence of chemical catalysts, before being catalysed by enzymes which were the products of later Darwinian selection. The enzymes were probably selected for their efficient catalytic activities during evolution from large libraries of vesicles containing amino acids, carbohydrates, nucleic acids, lipids, and meteorite components that induced symmetry imbalance.

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Powner, Matthew W, e John D Sutherland. "Phosphate-Mediated Interconversion of Ribo- and Arabino-Configured Prebiotic Nucleotide Intermediates". Angewandte Chemie International Edition 49, n.º 27 (20 de maio de 2010): 4641–43. http://dx.doi.org/10.1002/anie.201001662.

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Teller, Gérard, Yoichi Nakatani, Guy Ourisson, Martin Keller, Doris Hafenbradl e Karl O. Stetter. "A One-Step Synthesis of Squalene from Farnesol under Prebiotic Conditions". Angewandte Chemie International Edition in English 34, n.º 17 (15 de setembro de 1995): 1898–900. http://dx.doi.org/10.1002/anie.199518981.

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Boulanger, Eliot, Anakuthil Anoop, Dana Nachtigallova, Walter Thiel e Mario Barbatti. "Photochemical Steps in the Prebiotic Synthesis of Purine Precursors from HCN". Angewandte Chemie International Edition 52, n.º 31 (19 de junho de 2013): 8000–8003. http://dx.doi.org/10.1002/anie.201303246.

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Benner, Steven A., Hyo-Joong Kim e Elisa Biondi. "Prebiotic Chemistry that Could Not Not Have Happened". Life 9, n.º 4 (14 de novembro de 2019): 84. http://dx.doi.org/10.3390/life9040084.

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We present a direct route by which RNA might have emerged in the Hadean from a fayalite–magnetite mantle, volcanic SO2 gas, and well-accepted processes that must have created substantial amounts of HCHO and catalytic amounts of glycolaldehyde in the Hadean atmosphere. In chemistry that could not not have happened, these would have generated stable bisulfite addition products that must have rained to the surface, where they unavoidably would have slowly released reactive species that generated higher carbohydrates. The formation of higher carbohydrates is self-limited by bisulfite formation, while borate minerals may have controlled aldol reactions that occurred on any semi-arid surface to capture that precipitation. All of these processes have well-studied laboratory correlates. Further, any semi-arid land with phosphate should have had phosphate anhydrides that, with NH3, gave carbohydrate derivatives that directly react with nucleobases to form the canonical nucleosides. These are phosphorylated by magnesium borophosphate minerals (e.g., lüneburgite) and/or trimetaphosphate-borate with Ni2+ catalysis to give nucleoside 5′-diphosphates, which oligomerize to RNA via a variety of mechanisms. The reduced precursors that are required to form the nucleobases came, in this path-hypothesis, from one or more mid-sized (1023–1020 kg) impactors that almost certainly arrived after the Moon-forming event. Their iron metal content almost certainly generated ammonia, nucleobase precursors, and other reduced species in the Hadean atmosphere after it transiently placed the atmosphere out of redox equilibrium with the mantle. In addition to the inevitability of steps in this path-hypothesis on a Hadean Earth if it had semi-arid land, these processes may also have occurred on Mars. Adapted from a lecture by the Corresponding Author at the All-Russia Science Festival at the Lomonosov Moscow State University on 12 October 2019, and is an outcome of a three year project supported by the John Templeton Foundation and the NASA Astrobiology program. Dedicated to David Deamer, on the occasion of his 80th Birthday.

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