1
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Goldford JE, Smith HB, Longo LM, Wing BA, McGlynn SE. Primitive purine biosynthesis connects ancient geochemistry to modern metabolism. Nat Ecol Evol 2024; 8:999-1009. [PMID: 38519634 DOI: 10.1038/s41559-024-02361-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 02/06/2024] [Indexed: 03/25/2024]
Abstract
An unresolved question in the origin and evolution of life is whether a continuous path from geochemical precursors to the majority of molecules in the biosphere can be reconstructed from modern-day biochemistry. Here we identified a feasible path by simulating the evolution of biosphere-scale metabolism, using only known biochemical reactions and models of primitive coenzymes. We find that purine synthesis constitutes a bottleneck for metabolic expansion, which can be alleviated by non-autocatalytic phosphoryl coupling agents. Early phases of the expansion are enriched with enzymes that are metal dependent and structurally symmetric, supporting models of early biochemical evolution. This expansion trajectory suggests distinct hypotheses regarding the tempo, mode and timing of metabolic pathway evolution, including a late appearance of methane metabolisms and oxygenic photosynthesis consistent with the geochemical record. The concordance between biological and geological analyses suggests that this trajectory provides a plausible evolutionary history for the vast majority of core biochemistry.
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Affiliation(s)
- Joshua E Goldford
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA.
- Physics of Living Systems, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Blue Marble Space Institute of Science, Seattle, WA, USA.
| | - Harrison B Smith
- Blue Marble Space Institute of Science, Seattle, WA, USA
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Liam M Longo
- Blue Marble Space Institute of Science, Seattle, WA, USA
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Boswell A Wing
- Department of Geological Sciences, University of Colorado, Boulder, CO, USA
| | - Shawn Erin McGlynn
- Blue Marble Space Institute of Science, Seattle, WA, USA.
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan.
- Biofunctional Catalyst Research Team, RIKEN Center for Sustainable Resource Science, Wako, Japan.
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2
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Karaś P, Kochanowicz K, Pitek M, Domanski P, Obuchowski I, Tomiczek B, Liberek K. Evolution towards simplicity in bacterial small heat shock protein system. eLife 2023; 12:RP89813. [PMID: 38063373 PMCID: PMC10708888 DOI: 10.7554/elife.89813] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2023] Open
Abstract
Evolution can tinker with multi-protein machines and replace them with simpler single-protein systems performing equivalent functions in an equally efficient manner. It is unclear how, on a molecular level, such simplification can arise. With ancestral reconstruction and biochemical analysis, we have traced the evolution of bacterial small heat shock proteins (sHsp), which help to refold proteins from aggregates using either two proteins with different functions (IbpA and IbpB) or a secondarily single sHsp that performs both functions in an equally efficient way. Secondarily single sHsp evolved from IbpA, an ancestor specialized in strong substrate binding. Evolution of an intermolecular binding site drove the alteration of substrate binding properties, as well as the formation of higher-order oligomers. Upon two mutations in the α-crystallin domain, secondarily single sHsp interacts with aggregated substrates less tightly. Paradoxically, less efficient binding positively influences the ability of sHsp to stimulate substrate refolding, since the dissociation of sHps from aggregates is required to initiate Hsp70-Hsp100-dependent substrate refolding. After the loss of a partner, IbpA took over its role in facilitating the sHsp dissociation from an aggregate by weakening the interaction with the substrate, which became beneficial for the refolding process. We show that the same two amino acids introduced in modern-day systems define whether the IbpA acts as a single sHsp or obligatorily cooperates with an IbpB partner. Our discoveries illuminate how one sequence has evolved to encode functions previously performed by two distinct proteins.
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Affiliation(s)
- Piotr Karaś
- Intercollegiate Faculty of Biotechnology UG-MUG, University of GdanskGdańskPoland
| | - Klaudia Kochanowicz
- Intercollegiate Faculty of Biotechnology UG-MUG, University of GdanskGdańskPoland
| | - Marcin Pitek
- Intercollegiate Faculty of Biotechnology UG-MUG, University of GdanskGdańskPoland
| | - Przemyslaw Domanski
- Intercollegiate Faculty of Biotechnology UG-MUG, University of GdanskGdańskPoland
| | - Igor Obuchowski
- Intercollegiate Faculty of Biotechnology UG-MUG, University of GdanskGdańskPoland
| | - Barlomiej Tomiczek
- Intercollegiate Faculty of Biotechnology UG-MUG, University of GdanskGdańskPoland
| | - Krzysztof Liberek
- Intercollegiate Faculty of Biotechnology UG-MUG, University of GdanskGdańskPoland
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3
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Brown SM, Mayer-Bacon C, Freeland S. Xeno Amino Acids: A Look into Biochemistry as We Do Not Know It. Life (Basel) 2023; 13:2281. [PMID: 38137883 PMCID: PMC10744825 DOI: 10.3390/life13122281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 11/18/2023] [Accepted: 11/20/2023] [Indexed: 12/24/2023] Open
Abstract
Would another origin of life resemble Earth's biochemical use of amino acids? Here, we review current knowledge at three levels: (1) Could other classes of chemical structure serve as building blocks for biopolymer structure and catalysis? Amino acids now seem both readily available to, and a plausible chemical attractor for, life as we do not know it. Amino acids thus remain important and tractable targets for astrobiological research. (2) If amino acids are used, would we expect the same L-alpha-structural subclass used by life? Despite numerous ideas, it is not clear why life favors L-enantiomers. It seems clearer, however, why life on Earth uses the shortest possible (alpha-) amino acid backbone, and why each carries only one side chain. However, assertions that other backbones are physicochemically impossible have relaxed into arguments that they are disadvantageous. (3) Would we expect a similar set of side chains to those within the genetic code? Many plausible alternatives exist. Furthermore, evidence exists for both evolutionary advantage and physicochemical constraint as explanatory factors for those encoded by life. Overall, as focus shifts from amino acids as a chemical class to specific side chains used by post-LUCA biology, the probable role of physicochemical constraint diminishes relative to that of biological evolution. Exciting opportunities now present themselves for laboratory work and computing to explore how changing the amino acid alphabet alters the universe of protein folds. Near-term milestones include: (a) expanding evidence about amino acids as attractors within chemical evolution; (b) extending characterization of other backbones relative to biological proteins; and (c) merging computing and laboratory explorations of structures and functions unlocked by xeno peptides.
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4
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Tagami S. Why we are made of proteins and nucleic acids: Structural biology views on extraterrestrial life. Biophys Physicobiol 2023; 20:e200026. [PMID: 38496239 PMCID: PMC10941967 DOI: 10.2142/biophysico.bppb-v20.0026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 05/29/2023] [Indexed: 03/19/2024] Open
Abstract
Is it a miracle that life exists on the Earth, or is it a common phenomenon in the universe? If extraterrestrial organisms exist, what are they like? To answer these questions, we must understand what kinds of molecules could evolve into life, or in other words, what properties are generally required to perform biological functions and store genetic information. This review summarizes recent findings on simple ancestral proteins, outlines the basic knowledge in textbooks, and discusses the generally required properties for biological molecules from structural biology viewpoints (e.g., restriction of shapes, and types of intra- and intermolecular interactions), leading to the conclusion that proteins and nucleic acids are at least one of the simplest (and perhaps very common) forms of catalytic and genetic biopolymers in the universe. This review article is an extended version of the Japanese article, On the Origin of Life: Coevolution between RNA and Peptide, published in SEIBUTSU BUTSURI Vol. 61, p. 232-235 (2021).
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Affiliation(s)
- Shunsuke Tagami
- RIKEN Center for Biosystems Dynamics Research, Yokohama, Kanagawa 230-0045, Japan
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5
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Brown SM, Voráček V, Freeland S. What Would an Alien Amino Acid Alphabet Look Like and Why? ASTROBIOLOGY 2023; 23:536-549. [PMID: 37022727 DOI: 10.1089/ast.2022.0107] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Life on Earth builds genetically encoded proteins by using a standard alphabet of just 20 L-α-amino acids, although many others were available to life's origins and early evolution. To better understand the causes of this foundational evolutionary outcome, we extend previous analyses which have identified a highly unusual distribution of biophysical properties within the set used by life. Specifically, we use a heuristic search algorithm to identify other sets of amino acids, from a library of plausible alternatives, that emulate life's signature. We find that a subset of amino acids seems predisposed to forming such sets. We present other examples of such alphabets under various assumptions, along with analysis and reasoning about why each might be simplistic. We do so to introduce the central, open question that remains: while fundamental biophysics related to protein folding can potentially reduce a library of 1054 possible amino acid alphabets by 7 orders of magnitude, the framework of assumptions that does so leaves a further 1045 possibilities. It is therefore tempting to ask what additional assumptions can further reduce these 45 orders of magnitude? We thus conclude with a focus on library and alphabet construction as a useful target for subsequent research that may help future science speak with more confidence about what an alien amino acid alphabet would look like and why.
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Affiliation(s)
- Sean M Brown
- Department of Biological Sciences, University of Maryland, Baltimore County, Maryland, USA
| | - Václav Voráček
- Department of Computer Science, University of Tübingen, Tübingen, Germany
| | - Stephen Freeland
- Department of Biological Sciences, University of Maryland, Baltimore County, Maryland, USA
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6
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Makarov M, Sanchez Rocha AC, Krystufek R, Cherepashuk I, Dzmitruk V, Charnavets T, Faustino AM, Lebl M, Fujishima K, Fried SD, Hlouchova K. Early Selection of the Amino Acid Alphabet Was Adaptively Shaped by Biophysical Constraints of Foldability. J Am Chem Soc 2023; 145:5320-5329. [PMID: 36826345 PMCID: PMC10017022 DOI: 10.1021/jacs.2c12987] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Whereas modern proteins rely on a quasi-universal repertoire of 20 canonical amino acids (AAs), numerous lines of evidence suggest that ancient proteins relied on a limited alphabet of 10 "early" AAs and that the 10 "late" AAs were products of biosynthetic pathways. However, many nonproteinogenic AAs were also prebiotically available, which begs two fundamental questions: Why do we have the current modern amino acid alphabet and would proteins be able to fold into globular structures as well if different amino acids comprised the genetic code? Here, we experimentally evaluate the solubility and secondary structure propensities of several prebiotically relevant amino acids in the context of synthetic combinatorial 25-mer peptide libraries. The most prebiotically abundant linear aliphatic and basic residues were incorporated along with or in place of other early amino acids to explore these alternative sequence spaces. The results show that foldability was likely a critical factor in the selection of the canonical alphabet. Unbranched aliphatic amino acids were purged from the proteinogenic alphabet despite their high prebiotic abundance because they generate polypeptides that are oversolubilized and have low packing efficiency. Surprisingly, we find that the inclusion of a short-chain basic amino acid also decreases polypeptides' secondary structure potential, for which we suggest a biophysical model. Our results support the view that, despite lacking basic residues, the early canonical alphabet was remarkably adaptive at supporting protein folding and explain why basic residues were only incorporated at a later stage of protein evolution.
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Affiliation(s)
- Mikhail Makarov
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, Prague 12843, Czech Republic
| | - Alma C Sanchez Rocha
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, Prague 12843, Czech Republic
| | - Robin Krystufek
- Department of Physical Chemistry, Faculty of Science, Charles University, Prague 12843, Czech Republic.,Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague 16610, Czech Republic
| | - Ivan Cherepashuk
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, Prague 12843, Czech Republic
| | - Volha Dzmitruk
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Vestec 25250, Czech Republic
| | - Tatsiana Charnavets
- Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV, Vestec 25250, Czech Republic
| | - Anneliese M Faustino
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Michal Lebl
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague 16610, Czech Republic
| | - Kosuke Fujishima
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo 1528550, Japan.,Graduate School of Media and Governance, Keio University, Fujisawa 2520882, Japan
| | - Stephen D Fried
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States.,T. C. Jenkins Department of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Klara Hlouchova
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, Prague 12843, Czech Republic.,Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague 16610, Czech Republic
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7
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Zhao F, Akanuma S. Ancestral Sequence Reconstruction of the Ribosomal Protein uS8 and Reduction of Amino Acid Usage to a Smaller Alphabet. J Mol Evol 2023; 91:10-23. [PMID: 36396786 DOI: 10.1007/s00239-022-10078-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 11/08/2022] [Indexed: 11/19/2022]
Abstract
Understanding the origin and early evolution of proteins is important for unveiling how the RNA world developed into an RNA-protein world. Because the composition of organic molecules in the Earth's primitive environment was plausibly not as diverse as today, the number of different amino acids used in early protein synthesis is likely to be substantially less than the current 20 proteinogenic residues. In this study, we have explored the thermal stability and RNA binding of ancestral variants of the ribosomal protein uS8 constructed from a reduced-alphabet of amino acids. First, we built a phylogenetic tree based on the amino acid sequences of uS8 from multiple extant organisms and used the tree to infer two plausible amino acid sequences corresponding to the last bacterial common ancestor of uS8. Both ancestral proteins were thermally stable and bound to an RNA fragment. By eliminating individual amino acid letters and monitoring thermal stability and RNA binding in the resulting proteins, we reduced the size of the amino acid set constituting one of the ancestral proteins, eventually finding that convergent sequences consisting of 15- or 14-amino acid alphabets still folded into stable structures that bound to the RNA fragment. Furthermore, a simplified variant reconstructed from a 13-amino-acid alphabet retained affinity for the RNA fragment, although it lost conformational stability. Collectively, RNA-binding activity may be achieved with a subset of the current 20 amino acids, raising the possibility of a simpler composition of RNA-binding proteins in the earliest stage of protein evolution.
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Affiliation(s)
- Fangzheng Zhao
- Faculty of Human Sciences, Waseda University, 2-579-15, Mikajima, Tokorozawa, Saitama, 359-1192, Japan
| | - Satoshi Akanuma
- Faculty of Human Sciences, Waseda University, 2-579-15, Mikajima, Tokorozawa, Saitama, 359-1192, Japan.
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8
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Thoma B, Powner MW. Selective Synthesis of Lysine Peptides and the Prebiotically Plausible Synthesis of Catalytically Active Diaminopropionic Acid Peptide Nitriles in Water. J Am Chem Soc 2023; 145:3121-3130. [PMID: 36700882 PMCID: PMC9912261 DOI: 10.1021/jacs.2c12497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Why life encodes specific proteinogenic amino acids remains an unsolved problem, but a non-enzymatic synthesis that recapitulates biology's universal strategy of stepwise N-to-C terminal peptide growth may hold the key to this selection. Lysine is an important proteinogenic amino acid that, despite its essential structural, catalytic, and functional roles in biochemistry, has widely been assumed to be a late addition to the genetic code. Here, we demonstrate that lysine thioacids undergo coupling with aminonitriles in neutral water to afford peptides in near-quantitative yield, whereas non-proteinogenic lysine homologues, ornithine, and diaminobutyric acid cannot form peptides due to rapid and quantitative cyclization that irreversibly blocks peptide synthesis. We demonstrate for the first time that ornithine lactamization provides an absolute differentiation of lysine and ornithine during (non-enzymatic) N-to-C-terminal peptide ligation. We additionally demonstrate that the shortest lysine homologue, diaminopropionic acid, undergoes effective peptide ligation. This prompted us to discover a high-yielding prebiotically plausible synthesis of the diaminopropionic acid residue, by peptide nitrile modification, through the addition of ammonia to a dehydroalanine nitrile. With this synthesis in hand, we then discovered that the low basicity of diaminopropionyl residues promotes effective, biomimetic, imine catalysis in neutral water. Our results suggest diaminopropionic acid, synthesized by peptide nitrile modification, can replace or augment lysine residues during early evolution but that lysine's electronically isolated sidechain amine likely provides an evolutionary advantage for coupling and coding as a preformed monomer in monomer-by-monomer peptide translation.
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9
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Ma L, Fang X, Wang C. Peptide-based coacervates in therapeutic applications. Front Bioeng Biotechnol 2023; 10:1100365. [PMID: 36686257 PMCID: PMC9845597 DOI: 10.3389/fbioe.2022.1100365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 12/12/2022] [Indexed: 01/06/2023] Open
Abstract
Coacervates are droplets formed by liquid‒liquid phase separation. An increasing number of studies have reported that coacervates play an important role in living cells, such as in the generation of membraneless organelles, and peptides contribute to condensate droplet formation. Peptides with versatile functional groups and special secondary structures, including α-helices, β-sheets and intrinsically disordered regions, provide novel insights into coacervation, such as biomimetic protocells, neurodegenerative diseases, modulations of signal transmission, and drug delivery systems. In this review, we introduce different types of peptide-based coacervates and the principles of their interactions. Additionally, we summarize the thermodynamic and kinetic mechanisms of peptide-based coacervates and the associated factors, including salt, pH, and temperature, affecting the phase separation process. We illustrate recent studies on modulating the functions of peptide-based coacervates applied in biological diseases. Finally, we propose their promising broad applications and describe the challenges of peptide-based coacervates in the future.
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Affiliation(s)
- Lilusi Ma
- CAS Key Laboratory of Biological Effects of Nanomaterials and Nanosafety, CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, China,University of Chinese Academy of Sciences, Beijing, China
| | - Xiaocui Fang
- CAS Key Laboratory of Biological Effects of Nanomaterials and Nanosafety, CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, China,University of Chinese Academy of Sciences, Beijing, China,*Correspondence: Xiaocui Fang, ; Chen Wang,
| | - Chen Wang
- CAS Key Laboratory of Biological Effects of Nanomaterials and Nanosafety, CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, China,University of Chinese Academy of Sciences, Beijing, China,*Correspondence: Xiaocui Fang, ; Chen Wang,
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10
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Yuan L, Liu G, Zhao D, Zhu H, Qi J, Lu K. Interaction of p53 with BRC analogs: A comparative design assisted by ZDOCK and CABS-Dock simulation. J Mol Struct 2023. [DOI: 10.1016/j.molstruc.2022.134109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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11
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Wei Y, Wang Z, Liu Y, Liao B, Zong Y, Shi Y, Liao M, Wang J, Zhou X, Cheng L, Ren B. Extracellular vesicles of Candida albicans regulate its own growth through the l-arginine/nitric oxide pathway. Appl Microbiol Biotechnol 2022; 107:355-367. [PMCID: PMC9703431 DOI: 10.1007/s00253-022-12300-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 11/12/2022] [Accepted: 11/15/2022] [Indexed: 11/29/2022]
Affiliation(s)
- Yu Wei
- State Key Laboratory of Oral Diseases &, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
| | - Zheng Wang
- State Key Laboratory of Oral Diseases &, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
| | - Yaqi Liu
- State Key Laboratory of Oral Diseases &, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
| | - Binyou Liao
- State Key Laboratory of Oral Diseases &, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
| | - Yawen Zong
- State Key Laboratory of Oral Diseases &, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
| | - Yangyang Shi
- State Key Laboratory of Oral Diseases &, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
| | - Min Liao
- State Key Laboratory of Oral Diseases &, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
| | - Jiannan Wang
- State Key Laboratory of Oral Diseases &, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
| | - Xuedong Zhou
- State Key Laboratory of Oral Diseases &, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
| | - Lei Cheng
- State Key Laboratory of Oral Diseases &, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
- Department of Operative Dentistry and Endodontics, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
| | - Biao Ren
- State Key Laboratory of Oral Diseases &, National Clinical Research Center for Oral Diseases, West China School of Stomatology, Sichuan University, Chengdu, 610000 Sichuan Province China
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12
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Seal M, Weil-Ktorza O, Despotović D, Tawfik DS, Levy Y, Metanis N, Longo LM, Goldfarb D. Correction to “Peptide-RNA Coacervates as a Cradle for the Evolution of Folded Domains”. J Am Chem Soc 2022; 144:20976. [DOI: 10.1021/jacs.2c11057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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13
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A Closer Look at Non-random Patterns Within Chemistry Space for a Smaller, Earlier Amino Acid Alphabet. J Mol Evol 2022; 90:307-323. [PMID: 35666290 DOI: 10.1007/s00239-022-10061-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 05/11/2022] [Indexed: 10/18/2022]
Abstract
Recent findings, in vitro and in silico, are strengthening the idea of a simpler, earlier stage of genetically encoded proteins which used amino acids produced by prebiotic chemistry. These findings motivate a re-examination of prior work which has identified unusual properties of the set of twenty amino acids found within the full genetic code, while leaving it unclear whether similar patterns also characterize the subset of prebiotically plausible amino acids. We have suggested previously that this ambiguity may result from the low number of amino acids recognized by the definition of prebiotic plausibility used for the analysis. Here, we test this hypothesis using significantly updated data for organic material detected within meteorites, which contain several coded and non-coded amino acids absent from prior studies. In addition to confirming the well-established idea that "late" arriving amino acids expanded the chemistry space encoded by genetic material, we find that a prebiotically plausible subset of coded amino acids generally emulates the patterns found in the full set of 20, namely an exceptionally broad and even distribution of volumes and an exceptionally even distribution of hydrophobicities (quantified as logP) over a narrow range. However, the strength of this pattern varies depending on both the size and composition the library used to create a background (null model) for a random alphabet, and the precise definition of exactly which amino acids were present in a simpler, earlier code. Findings support the idea that a small sample size of amino acids caused previous ambiguous results, and further improvements in meteorite analysis, and/or prebiotic simulations will further clarify the nature and extent of unusual properties. We discuss the case of sulfur-containing amino acids as a specific and clear example and conclude by reviewing the potential impact of better understanding the chemical "logic" of a smaller forerunner to the standard amino acid alphabet.
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14
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Tretyachenko V, Vymětal J, Neuwirthová T, Vondrášek J, Fujishima K, Hlouchová K. Modern and prebiotic amino acids support distinct structural profiles in proteins. Open Biol 2022; 12:220040. [PMID: 35728622 PMCID: PMC9213115 DOI: 10.1098/rsob.220040] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The earliest proteins had to rely on amino acids available on early Earth before the biosynthetic pathways for more complex amino acids evolved. In extant proteins, a significant fraction of the 'late' amino acids (such as Arg, Lys, His, Cys, Trp and Tyr) belong to essential catalytic and structure-stabilizing residues. How (or if) early proteins could sustain an early biosphere has been a major puzzle. Here, we analysed two combinatorial protein libraries representing proxies of the available sequence space at two different evolutionary stages. The first is composed of the entire alphabet of 20 amino acids while the second one consists of only 10 residues (ASDGLIPTEV) representing a consensus view of plausibly available amino acids through prebiotic chemistry. We show that compact conformations resistant to proteolysis are surprisingly similarly abundant in both libraries. In addition, the early alphabet proteins are inherently more soluble and refoldable, independent of the general Hsp70 chaperone activity. By contrast, chaperones significantly increase the otherwise poor solubility of the modern alphabet proteins suggesting their coevolution with the amino acid repertoire. Our work indicates that while both early and modern amino acids are predisposed to supporting protein structure, they do so with different biophysical properties and via different mechanisms.
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Affiliation(s)
- Vyacheslav Tretyachenko
- Department of Cell Biology, Faculty of Science, Charles University, Prague 12843, Czech Republic,Department of Biochemistry, Faculty of Science, Charles University, Prague 12843, Czech Republic
| | - Jiří Vymětal
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague 16610, Czech Republic
| | - Tereza Neuwirthová
- Department of Cell Biology, Faculty of Science, Charles University, Prague 12843, Czech Republic
| | - Jiří Vondrášek
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague 16610, Czech Republic
| | - Kosuke Fujishima
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo 1528550, Japan,Graduate School of Media and Governance, Keio University, Fujisawa 2520882 Japan
| | - Klára Hlouchová
- Department of Cell Biology, Faculty of Science, Charles University, Prague 12843, Czech Republic,Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague 16610, Czech Republic
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15
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Fried SD, Fujishima K, Makarov M, Cherepashuk I, Hlouchova K. Peptides before and during the nucleotide world: an origins story emphasizing cooperation between proteins and nucleic acids. J R Soc Interface 2022; 19:20210641. [PMID: 35135297 PMCID: PMC8833103 DOI: 10.1098/rsif.2021.0641] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Recent developments in Origins of Life research have focused on substantiating the narrative of an abiotic emergence of nucleic acids from organic molecules of low molecular weight, a paradigm that typically sidelines the roles of peptides. Nevertheless, the simple synthesis of amino acids, the facile nature of their activation and condensation, their ability to recognize metals and cofactors and their remarkable capacity to self-assemble make peptides (and their analogues) favourable candidates for one of the earliest functional polymers. In this mini-review, we explore the ramifications of this hypothesis. Diverse lines of research in molecular biology, bioinformatics, geochemistry, biophysics and astrobiology provide clues about the progression and early evolution of proteins, and lend credence to the idea that early peptides served many central prebiotic roles before they were encodable by a polynucleotide template, in a putative 'peptide-polynucleotide stage'. For example, early peptides and mini-proteins could have served as catalysts, compartments and structural hubs. In sum, we shed light on the role of early peptides and small proteins before and during the nucleotide world, in which nascent life fully grasped the potential of primordial proteins, and which has left an imprint on the idiosyncratic properties of extant proteins.
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Affiliation(s)
- Stephen D Fried
- Department of Chemistry, Johns Hopkins University, Baltimore, MD 21212, USA.,Department of Biophysics, Johns Hopkins University, Baltimore, MD 21212, USA
| | - Kosuke Fujishima
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo 1528550, Japan.,Graduate School of Media and Governance, Keio University, Fujisawa 2520882, Japan
| | - Mikhail Makarov
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, Prague 12800, Czech Republic
| | - Ivan Cherepashuk
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, Prague 12800, Czech Republic
| | - Klara Hlouchova
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, Prague 12800, Czech Republic.,Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague 16610, Czech Republic
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16
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Giacobelli VG, Fujishima K, Lepšík M, Tretyachenko V, Kadavá T, Makarov M, Bednárová L, Novák P, Hlouchová K. In vitro evolution reveals non-cationic protein-RNA interaction mediated by metal ions. Mol Biol Evol 2022; 39:6524634. [PMID: 35137196 PMCID: PMC8892947 DOI: 10.1093/molbev/msac032] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
RNA–peptide/protein interactions have been of utmost importance to life since its earliest forms, reaching even before the last universal common ancestor (LUCA). However, the ancient molecular mechanisms behind this key biological interaction remain enigmatic because extant RNA–protein interactions rely heavily on positively charged and aromatic amino acids that were absent (or heavily under-represented) in the early pre-LUCA evolutionary period. Here, an RNA-binding variant of the ribosomal uL11 C-terminal domain was selected from an approximately 1010 library of partially randomized sequences, all composed of ten prebiotically plausible canonical amino acids. The selected variant binds to the cognate RNA with a similar overall affinity although it is less structured in the unbound form than the wild-type protein domain. The variant complex association and dissociation are both slower than for the wild-type, implying different mechanistic processes involved. The profile of the wild-type and mutant complex stabilities along with molecular dynamics simulations uncovers qualitative differences in the interaction modes. In the absence of positively charged and aromatic residues, the mutant uL11 domain uses ion bridging (K+/Mg2+) interactions between the RNA sugar-phosphate backbone and glutamic acid residues as an alternative source of stabilization. This study presents experimental support to provide a new perspective on how early protein–RNA interactions evolved, where the lack of aromatic/basic residues may have been compensated by acidic residues plus metal ions.
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Affiliation(s)
- Valerio G Giacobelli
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, Prague, 12800, Czech Republic
| | - Kosuke Fujishima
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, 1528550, Japan.,Graduate School of Media and Governance, Keio University, Fujisawa, 2520882, Japan
| | - Martin Lepšík
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague, 16610, Czech Republic
| | - Vyacheslav Tretyachenko
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, Prague, 12800, Czech Republic
| | - Tereza Kadavá
- Department of Biochemistry, Faculty of Science, Charles University, Prague, 12800, Czech Republic
| | - Mikhail Makarov
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, Prague, 12800, Czech Republic
| | - Lucie Bednárová
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague, 16610, Czech Republic
| | - Petr Novák
- Institute of Microbiology, The Czech Academy of Sciences, Vestec, 25250, Czech Republic
| | - Klára Hlouchová
- Department of Cell Biology, Faculty of Science, Charles University, BIOCEV, Prague, 12800, Czech Republic.,Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Prague, 16610, Czech Republic
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17
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Longo LM, Kolodny R, McGlynn SE. Evidence for the emergence of β-trefoils by 'Peptide Budding' from an IgG-like β-sandwich. PLoS Comput Biol 2022; 18:e1009833. [PMID: 35157697 PMCID: PMC8880906 DOI: 10.1371/journal.pcbi.1009833] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 02/25/2022] [Accepted: 01/13/2022] [Indexed: 12/02/2022] Open
Abstract
As sequence and structure comparison algorithms gain sensitivity, the intrinsic interconnectedness of the protein universe has become increasingly apparent. Despite this general trend, β-trefoils have emerged as an uncommon counterexample: They are an isolated protein lineage for which few, if any, sequence or structure associations to other lineages have been identified. If β-trefoils are, in fact, remote islands in sequence-structure space, it implies that the oligomerizing peptide that founded the β-trefoil lineage itself arose de novo. To better understand β-trefoil evolution, and to probe the limits of fragment sharing across the protein universe, we identified both 'β-trefoil bridging themes' (evolutionarily-related sequence segments) and 'β-trefoil-like motifs' (structure motifs with a hallmark feature of the β-trefoil architecture) in multiple, ostensibly unrelated, protein lineages. The success of the present approach stems, in part, from considering β-trefoil sequence segments or structure motifs rather than the β-trefoil architecture as a whole, as has been done previously. The newly uncovered inter-lineage connections presented here suggest a novel hypothesis about the origins of the β-trefoil fold itself-namely, that it is a derived fold formed by 'budding' from an Immunoglobulin-like β-sandwich protein. These results demonstrate how the evolution of a folded domain from a peptide need not be a signature of antiquity and underpin an emerging truth: few protein lineages escape nature's sewing table.
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Affiliation(s)
- Liam M. Longo
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
- Blue Marble Space Institute of Science, Seattle, Washington, United States of America
| | - Rachel Kolodny
- Department of Computer Science, University of Haifa, Haifa, Israel
| | - Shawn E. McGlynn
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
- Blue Marble Space Institute of Science, Seattle, Washington, United States of America
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18
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Jackson C, Toth-Petroczy A, Kolodny R, Hollfelder F, Fuxreiter M, Caroline Lynn Kamerlin S, Tokuriki N. Adventures on the routes of protein evolution — in memoriam Dan Salah Tawfik (1955 - 2021). J Mol Biol 2022; 434:167462. [DOI: 10.1016/j.jmb.2022.167462] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 01/17/2022] [Indexed: 12/21/2022]
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19
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Lewis AJO, Hegde RS. A unified evolutionary origin for the ubiquitous protein transporters SecY and YidC. BMC Biol 2021; 19:266. [PMID: 34911545 PMCID: PMC8675477 DOI: 10.1186/s12915-021-01171-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 10/21/2021] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Protein transporters translocate hydrophilic segments of polypeptide across hydrophobic cell membranes. Two protein transporters are ubiquitous and date back to the last universal common ancestor: SecY and YidC. SecY consists of two pseudosymmetric halves, which together form a membrane-spanning protein-conducting channel. YidC is an asymmetric molecule with a protein-conducting hydrophilic groove that partially spans the membrane. Although both transporters mediate insertion of membrane proteins with short translocated domains, only SecY transports secretory proteins and membrane proteins with long translocated domains. The evolutionary origins of these ancient and essential transporters are not known. RESULTS The features conserved by the two halves of SecY indicate that their common ancestor was an antiparallel homodimeric channel. Structural searches with SecY's halves detect exceptional similarity with YidC homologs. The SecY halves and YidC share a fold comprising a three-helix bundle interrupted by a helical hairpin. In YidC, this hairpin is cytoplasmic and facilitates substrate delivery, whereas in SecY, it is transmembrane and forms the substrate-binding lateral gate helices. In both transporters, the three-helix bundle forms a protein-conducting hydrophilic groove delimited by a conserved hydrophobic residue. Based on these similarities, we propose that SecY originated as a YidC homolog which formed a channel by juxtaposing two hydrophilic grooves in an antiparallel homodimer. We find that archaeal YidC and its eukaryotic descendants use this same dimerisation interface to heterodimerise with a conserved partner. YidC's sufficiency for the function of simple cells is suggested by the results of reductive evolution in mitochondria and plastids, which tend to retain SecY only if they require translocation of large hydrophilic domains. CONCLUSIONS SecY and YidC share previously unrecognised similarities in sequence, structure, mechanism, and function. Our delineation of a detailed correspondence between these two essential and ancient transporters enables a deeper mechanistic understanding of how each functions. Furthermore, key differences between them help explain how SecY performs its distinctive function in the recognition and translocation of secretory proteins. The unified theory presented here explains the evolution of these features, and thus reconstructs a key step in the origin of cells.
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Affiliation(s)
- Aaron J O Lewis
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
| | - Ramanujan S Hegde
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
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20
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Rout SK, Rhyner D, Riek R, Greenwald J. Prebiotically Plausible Autocatalytic Peptide Amyloids. Chemistry 2021; 28:e202103841. [PMID: 34812556 PMCID: PMC9299922 DOI: 10.1002/chem.202103841] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Indexed: 12/19/2022]
Abstract
The prebiotic emergence of molecules capable both of self-replication and of storing information was a defining event at the dawn of life. Still, no plausible prebiotic self-replication of biologically relevant molecules has been demonstrated. Building upon the known templating nature of amyloids, we present two systems in which the products of a peptide-bond-forming reaction act as self-replicators to enhance the yield and stereoselectivity of their formation. This first report of an amino acid condensation that can undergo autocatalysis further supports the potential role of amyloids in prebiotic molecular evolution as an environment-responsive and information-coding system capable of self-replication.
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Affiliation(s)
- Saroj K Rout
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH Hönggerberg, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
| | - David Rhyner
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH Hönggerberg, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
| | - Roland Riek
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH Hönggerberg, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
| | - Jason Greenwald
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH Hönggerberg, Vladimir-Prelog-Weg 2, 8093, Zürich, Switzerland
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21
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Yagi S, Padhi AK, Vucinic J, Barbe S, Schiex T, Nakagawa R, Simoncini D, Zhang KYJ, Tagami S. Seven Amino Acid Types Suffice to Create the Core Fold of RNA Polymerase. J Am Chem Soc 2021; 143:15998-16006. [PMID: 34559526 DOI: 10.1021/jacs.1c05367] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The extant complex proteins must have evolved from ancient short and simple ancestors. The double-ψ β-barrel (DPBB) is one of the oldest protein folds and conserved in various fundamental enzymes, such as the core domain of RNA polymerase. Here, by reverse engineering a modern DPBB domain, we reconstructed its plausible evolutionary pathway started by "interlacing homodimerization" of a half-size peptide, followed by gene duplication and fusion. Furthermore, by simplifying the amino acid repertoire of the peptide, we successfully created the DPBB fold with only seven amino acid types (Ala, Asp, Glu, Gly, Lys, Arg, and Val), which can be coded by only GNN and ARR (R = A or G) codons in the modern translation system. Thus, the DPBB fold could have been materialized by the early translation system and genetic code.
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Affiliation(s)
- Sota Yagi
- RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Aditya K Padhi
- RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Jelena Vucinic
- Université Fédérale de Toulouse, ANITI, INRAE-UR 875, 31000 Toulouse, France.,TBI, Université Fédérale de Toulouse, CNRS, INRAE, INSA, ANITI, 31000 Toulouse, France.,Université Fédérale de Toulouse, ANITI, IRIT-UMR 5505, 31000 Toulouse, France
| | - Sophie Barbe
- TBI, Université Fédérale de Toulouse, CNRS, INRAE, INSA, ANITI, 31000 Toulouse, France
| | - Thomas Schiex
- Université Fédérale de Toulouse, ANITI, INRAE-UR 875, 31000 Toulouse, France
| | - Reiko Nakagawa
- RIKEN Center for Biosystems Dynamics Research, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
| | - David Simoncini
- Université Fédérale de Toulouse, ANITI, IRIT-UMR 5505, 31000 Toulouse, France
| | - Kam Y J Zhang
- RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Shunsuke Tagami
- RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
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22
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Affiliation(s)
- Amir Aharoni
- Department of Life Sciences Ben‐Gurion University of the Negev Be’er Sheva Israel
| | - Sarel J. Fleishman
- Department of Biomolecular Sciences Weizmann Institute of Science Rehovot Israel
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23
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The Origin(s) of Cell(s): Pre-Darwinian Evolution from FUCAs to LUCA : To Carl Woese (1928-2012), for his Conceptual Breakthrough of Cellular Evolution. J Mol Evol 2021; 89:427-447. [PMID: 34173011 DOI: 10.1007/s00239-021-10014-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Accepted: 05/29/2021] [Indexed: 10/21/2022]
Abstract
The coming of the Last Universal Cellular Ancestor (LUCA) was the singular watershed event in the making of the biotic world. If the coming of LUCA marked the crossing of the "Darwinian Threshold", then pre-LUCA evolution must have been Pre-Darwinian and at least partly non-Darwinian. But how did Pre-Darwinian evolution before LUCA actually operate? I broaden our understanding of the central mechanism of biological evolution (i.e., variation-selection-inheritance) and then extend this broadened understanding to its natural starting point: the origin(s) of the First Universal Cellular Ancestors (FUCAs) before LUCA. My hypothesis centers upon vesicles' making-and-remaking as variation and competition as selection. More specifically, I argue that vesicles' acquisition and merger, via breaking-and-repacking, proto-endocytosis, proto-endosymbiosis, and other similar processes had been a central force of both variation and selection in the pre-Darwinian epoch. These new perspectives shed important new light upon the origin of FUCAs and their subsequent evolution into LUCA.
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24
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Guo W, Kinghorn AB, Zhang Y, Li Q, Poonam AD, Tanner JA, Shum HC. Non-associative phase separation in an evaporating droplet as a model for prebiotic compartmentalization. Nat Commun 2021; 12:3194. [PMID: 34045455 PMCID: PMC8160217 DOI: 10.1038/s41467-021-23410-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 04/22/2021] [Indexed: 11/13/2022] Open
Abstract
The synthetic pathways of life’s building blocks are envisaged to be through a series of complex prebiotic reactions and processes. However, the strategy to compartmentalize and concentrate biopolymers under prebiotic conditions remains elusive. Liquid-liquid phase separation is a mechanism by which membraneless organelles form inside cells, and has been hypothesized as a potential mechanism for prebiotic compartmentalization. Associative phase separation of oppositely charged species has been shown to partition RNA, but the strongly negative charge exhibited by RNA suggests that RNA-polycation interactions could inhibit RNA folding and its functioning inside the coacervates. Here, we present a prebiotically plausible pathway for non-associative phase separation within an evaporating all-aqueous sessile droplet. We quantitatively investigate the kinetic pathway of phase separation triggered by the non-uniform evaporation rate, together with the Marangoni flow-driven hydrodynamics inside the sessile droplet. With the ability to undergo liquid-liquid phase separation, the drying droplets provide a robust mechanism for formation of prebiotic membraneless compartments, as demonstrated by localization and storage of nucleic acids, in vitro transcription, as well as a three-fold enhancement of ribozyme activity. The compartmentalization mechanism illustrated in this model system is feasible on wet organophilic silica-rich surfaces during early molecular evolution. Prebiotic compartmentalization could prove essential for the evolution of life. Guo et al. show that liquid-liquid separation in an aqueous two-phase system driven by evaporation may already suffice to facilitate chemical processes required for the RNA world hypothesis.
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Affiliation(s)
- Wei Guo
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China
| | - Andrew B Kinghorn
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China
| | - Yage Zhang
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China
| | - Qingchuan Li
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China.,School of Chemistry & Chemical Engineering, National Engineering Research Center for Colloidal Materials, Shandong University, Jinan, 250100, China
| | - Aditi Dey Poonam
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China
| | - Julian A Tanner
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China. .,Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), Hong Kong, China.
| | - Ho Cheung Shum
- Department of Mechanical Engineering, Faculty of Engineering, The University of Hong Kong, Hong Kong (SAR), Hong Kong, China. .,Advanced Biomedical Instrumentation Centre, Hong Kong Science Park, Shatin, New Territories, Hong Kong (SAR), Hong Kong, China.
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25
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Kolodny R, Nepomnyachiy S, Tawfik DS, Ben-Tal N. Bridging Themes: Short Protein Segments Found in Different Architectures. Mol Biol Evol 2021; 38:2191-2208. [PMID: 33502503 PMCID: PMC8136508 DOI: 10.1093/molbev/msab017] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The vast majority of theoretically possible polypeptide chains do not fold, let alone confer function. Hence, protein evolution from preexisting building blocks has clear potential advantages over ab initio emergence from random sequences. In support of this view, sequence similarities between different proteins is generally indicative of common ancestry, and we collectively refer to such homologous sequences as "themes." At the domain level, sequence homology is routinely detected. However, short themes which are segments, or fragments of intact domains, are particularly interesting because they may provide hints about the emergence of domains, as opposed to divergence of preexisting domains, or their mixing-and-matching to form multi-domain proteins. Here we identified 525 representative short themes, comprising 20-80 residues that are unexpectedly shared between domains considered to have emerged independently. Among these "bridging themes" are ones shared between the most ancient domains, for example, Rossmann, P-loop NTPase, TIM-barrel, flavodoxin, and ferredoxin-like. We elaborate on several particularly interesting cases, where the bridging themes mediate ligand binding. Ligand binding may have contributed to the stability and the plasticity of these building blocks, and to their ability to invade preexisting domains or serve as starting points for completely new domains.
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Affiliation(s)
- Rachel Kolodny
- Department of Computer Science, University of Haifa, Haifa, Israel
| | | | - Dan S Tawfik
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Nir Ben-Tal
- George S. Wise Faculty of Life Sciences, Department of Biochemistry and Molecular Biology, Tel Aviv University, Tel Aviv, Israel
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26
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Abstract
Diverse models have been advanced for the evolution of the genetic code. Here, models for tRNA, aminoacyl-tRNA synthetase (aaRS) and genetic code evolution were combined with an understanding of EF-Tu suppression of tRNA 3rd anticodon position wobbling. The result is a highly detailed scheme that describes the placements of all amino acids in the standard genetic code. The model describes evolution of 6-, 4-, 3-, 2- and 1-codon sectors. Innovation in column 3 of the code is explained. Wobbling and code degeneracy are explained. Separate distribution of serine sectors between columns 2 and 4 of the code is described. We conclude that very little chaos contributed to evolution of the genetic code and that the pattern of evolution of aaRS enzymes describes a history of the evolution of the code. A model is proposed to describe the biological selection for the earliest evolution of the code and for protocell evolution.
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Affiliation(s)
- Lei Lei
- Department of Biology, University of New England, Biddeford, ME, USA
| | - Zachary Frome Burton
- Department of Biochemistry and Molecular Biology, Michigan State University, E. Lansing, MI, USA
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27
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Makarov M, Meng J, Tretyachenko V, Srb P, Březinová A, Giacobelli VG, Bednárová L, Vondrášek J, Dunker AK, Hlouchová K. Enzyme catalysis prior to aromatic residues: Reverse engineering of a dephospho-CoA kinase. Protein Sci 2021; 30:1022-1034. [PMID: 33739538 PMCID: PMC8040869 DOI: 10.1002/pro.4068] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 03/12/2021] [Accepted: 03/13/2021] [Indexed: 11/07/2022]
Abstract
The wide variety of protein structures and functions results from the diverse properties of the 20 canonical amino acids. The generally accepted hypothesis is that early protein evolution was associated with enrichment of a primordial alphabet, thereby enabling increased protein catalytic efficiencies and functional diversification. Aromatic amino acids were likely among the last additions to genetic code. The main objective of this study was to test whether enzyme catalysis can occur without the aromatic residues (aromatics) by studying the structure and function of dephospho-CoA kinase (DPCK) following aromatic residue depletion. We designed two variants of a putative DPCK from Aquifex aeolicus by substituting (a) Tyr, Phe and Trp or (b) all aromatics (including His). Their structural characterization indicates that substituting the aromatics does not markedly alter their secondary structures but does significantly loosen their side chain packing and increase their sizes. Both variants still possess ATPase activity, although with 150-300 times lower efficiency in comparison with the wild-type phosphotransferase activity. The transfer of the phosphate group to the dephospho-CoA substrate becomes heavily uncoupled and only the His-containing variant is still able to perform the phosphotransferase reaction. These data support the hypothesis that proteins in the early stages of life could support catalytic activities, albeit with low efficiencies. An observed significant contraction upon ligand binding is likely important for appropriate organization of the active site. Formation of firm hydrophobic cores, which enable the assembly of stably structured active sites, is suggested to provide a selective advantage for adding the aromatic residues.
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Affiliation(s)
- Mikhail Makarov
- Department of Cell Biology, Faculty of ScienceCharles University, BIOCEVPragueCzech Republic
- Department of Biochemistry, Faculty of ScienceCharles UniversityPragueCzech Republic
| | - Jingwei Meng
- Department of Biochemistry and Molecular Biology, Center for Computational Biology and BioinformaticsIndiana University School of MedicineIndianapolisIndianaUSA
| | - Vyacheslav Tretyachenko
- Department of Cell Biology, Faculty of ScienceCharles University, BIOCEVPragueCzech Republic
- Department of Biochemistry, Faculty of ScienceCharles UniversityPragueCzech Republic
| | - Pavel Srb
- Institute of Organic Chemistry and Biochemistry, IOCB Research Centre & Gilead Sciences, Academy of Sciences of the Czech RepublicPragueCzech Republic
| | - Anna Březinová
- Proteomics Core Facility, BIOCEV, Faculty of Science, Charles UniversityPragueCzech Republic
| | | | - Lucie Bednárová
- Institute of Organic Chemistry and Biochemistry, IOCB Research Centre & Gilead Sciences, Academy of Sciences of the Czech RepublicPragueCzech Republic
| | - Jiří Vondrášek
- Institute of Organic Chemistry and Biochemistry, IOCB Research Centre & Gilead Sciences, Academy of Sciences of the Czech RepublicPragueCzech Republic
| | - A. Keith Dunker
- Department of Biochemistry and Molecular Biology, Center for Computational Biology and BioinformaticsIndiana University School of MedicineIndianapolisIndianaUSA
| | - Klára Hlouchová
- Department of Cell Biology, Faculty of ScienceCharles University, BIOCEVPragueCzech Republic
- Institute of Organic Chemistry and Biochemistry, IOCB Research Centre & Gilead Sciences, Academy of Sciences of the Czech RepublicPragueCzech Republic
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28
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Helicase-like functions in phosphate loop containing beta-alpha polypeptides. Proc Natl Acad Sci U S A 2021; 118:2016131118. [PMID: 33846247 DOI: 10.1073/pnas.2016131118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The P-loop Walker A motif underlies hundreds of essential enzyme families that bind nucleotide triphosphates (NTPs) and mediate phosphoryl transfer (P-loop NTPases), including the earliest DNA/RNA helicases, translocases, and recombinases. What were the primordial precursors of these enzymes? Could these large and complex proteins emerge from simple polypeptides? Previously, we showed that P-loops embedded in simple βα repeat proteins bind NTPs but also, unexpectedly so, ssDNA and RNA. Here, we extend beyond the purely biophysical function of ligand binding to demonstrate rudimentary helicase-like activities. We further constructed simple 40-residue polypeptides comprising just one β-(P-loop)-α element. Despite their simplicity, these P-loop prototypes confer functions such as strand separation and exchange. Foremost, these polypeptides unwind dsDNA, and upon addition of NTPs, or inorganic polyphosphates, release the bound ssDNA strands to allow reformation of dsDNA. Binding kinetics and low-resolution structural analyses indicate that activity is mediated by oligomeric forms spanning from dimers to high-order assemblies. The latter are reminiscent of extant P-loop recombinases such as RecA. Overall, these P-loop prototypes compose a plausible description of the sequence, structure, and function of the earliest P-loop NTPases. They also indicate that multifunctionality and dynamic assembly were key in endowing short polypeptides with elaborate, evolutionarily relevant functions.
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Can coacervation unify disparate hypotheses in the origin of cellular life? Curr Opin Colloid Interface Sci 2021. [DOI: 10.1016/j.cocis.2020.101415] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Affiliation(s)
- Dragana Despotovic
- Department of Biomolecular Sciences Weizmann Institute of Science Rehovot 7610001 Israel
| | - Dan S. Tawfik
- Department of Biomolecular Sciences Weizmann Institute of Science Rehovot 7610001 Israel
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Tong CL, Lee KH, Seelig B. De novo proteins from random sequences through in vitro evolution. Curr Opin Struct Biol 2021; 68:129-134. [PMID: 33517151 DOI: 10.1016/j.sbi.2020.12.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 12/29/2020] [Indexed: 11/29/2022]
Abstract
Natural proteins are the result of billions of years of evolution. The earliest predecessors of today's proteins are believed to have emerged from random polypeptides. While we have no means to determine how this process exactly happened, there is great interest in understanding how it reasonably could have happened. We are reviewing how researchers have utilized in vitro selection and molecular evolution methods to investigate plausible scenarios for the emergence of early functional proteins. The studies range from analyzing general properties and structural features of unevolved random polypeptides to isolating de novo proteins with specific functions from synthetic randomized sequence libraries or generating novel proteins by combining evolution with rational design. While the results are exciting, more work is needed to fully unravel the mechanisms that seeded protein-dominated biology.
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Affiliation(s)
- Cher Ling Tong
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, USA; BioTechnology Institute, University of Minnesota, St. Paul, MN, USA
| | - Kun-Hwa Lee
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, USA; BioTechnology Institute, University of Minnesota, St. Paul, MN, USA
| | - Burckhard Seelig
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN, USA; BioTechnology Institute, University of Minnesota, St. Paul, MN, USA.
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Namani T, Snyder S, Eagan JM, Bevilacqua PC, Wesdemiotis C, Sahai N. Amino Acid Specific Nonenzymatic Montmorillonite‐Promoted RNA Polymerization. CHEMSYSTEMSCHEM 2021. [DOI: 10.1002/syst.202000060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Trishool Namani
- School of Polymer Science and Polymer Engineering The University of Akron Akron OH 44325 USA
| | - Savannah Snyder
- Department of Chemistry The University of Akron Akron OH 44325 USA
| | - James M. Eagan
- School of Polymer Science and Polymer Engineering The University of Akron Akron OH 44325 USA
| | - Philip C. Bevilacqua
- Department of Chemistry and Biochemistry Department of Microbiology and Molecular Biology Center for RNA Molecular Biology Pennsylvania State University University Park Pennsylvania PA 16802 USA
| | | | - Nita Sahai
- School of Polymer Science and Polymer Engineering The University of Akron Akron OH 44325 USA
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Searching protein space for ancient sub-domain segments. Curr Opin Struct Biol 2021; 68:105-112. [PMID: 33476896 DOI: 10.1016/j.sbi.2020.11.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Accepted: 11/29/2020] [Indexed: 01/08/2023]
Abstract
Evolutionary processes that formed the current protein universe left their traces, among them homologous segments that recur, or are 'reused,' in multiple proteins. These reused segments, called 'themes,' can be found at various scales, the best known of which is the domain. Yet, recent studies have begun to focus on the evolutionary insights that can be derived from sub-domain-scale themes, which are candidates for traces of more ancient events. Characterizing these may provide clues to the emergence of domains. Particularly interesting are themes that are reused across dissimilar contexts, that is, where the rest of the protein domain differs. We survey computational studies identifying reused themes within different contexts at the sub-domain level.
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Longo LM, Jabłońska J, Vyas P, Kanade M, Kolodny R, Ben-Tal N, Tawfik DS. On the emergence of P-Loop NTPase and Rossmann enzymes from a Beta-Alpha-Beta ancestral fragment. eLife 2020; 9:e64415. [PMID: 33295875 PMCID: PMC7758060 DOI: 10.7554/elife.64415] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 12/04/2020] [Indexed: 12/14/2022] Open
Abstract
This article is dedicated to the memory of Michael G. Rossmann. Dating back to the last universal common ancestor, P-loop NTPases and Rossmanns comprise the most ubiquitous and diverse enzyme lineages. Despite similarities in their overall architecture and phosphate binding motif, a lack of sequence identity and some fundamental structural differences currently designates them as independent emergences. We systematically searched for structure and sequence elements shared by both lineages. We detected homologous segments that span the first βαβ motif of both lineages, including the phosphate binding loop and a conserved aspartate at the tip of β2. The latter ligates the catalytic metal in P-loop NTPases, while in Rossmanns it binds the nucleotide's ribose moiety. Tubulin, a Rossmann GTPase, demonstrates the potential of the β2-Asp to take either one of these two roles. While convergence cannot be completely ruled out, we show that both lineages likely emerged from a common βαβ segment that comprises the core of these enzyme families to this very day.
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Affiliation(s)
- Liam M Longo
- Weizmann Institute of Science, Department of Biomolecular SciencesRehovotIsrael
| | - Jagoda Jabłońska
- Weizmann Institute of Science, Department of Biomolecular SciencesRehovotIsrael
| | - Pratik Vyas
- Weizmann Institute of Science, Department of Biomolecular SciencesRehovotIsrael
| | - Manil Kanade
- Weizmann Institute of Science, Department of Biomolecular SciencesRehovotIsrael
| | - Rachel Kolodny
- University of Haifa, Department of Computer ScienceHaifaIsrael
| | - Nir Ben-Tal
- Tel Aviv University, George S. Wise Faculty of Life Sciences, Department of Biochemistry and Molecular BiologyTel AvivIsrael
| | - Dan S Tawfik
- Weizmann Institute of Science, Department of Biomolecular SciencesRehovotIsrael
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Despotović D, Longo LM, Aharon E, Kahana A, Scherf T, Gruic-Sovulj I, Tawfik DS. Polyamines Mediate Folding of Primordial Hyperacidic Helical Proteins. Biochemistry 2020; 59:4456-4462. [PMID: 33175508 PMCID: PMC7735664 DOI: 10.1021/acs.biochem.0c00800] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 10/29/2020] [Indexed: 12/11/2022]
Abstract
Polyamines are known to mediate diverse biological processes, and specifically to bind and stabilize compact conformations of nucleic acids, acting as chemical chaperones that promote folding by offsetting the repulsive negative charges of the phosphodiester backbone. However, whether and how polyamines modulate the structure and function of proteins remain unclear. In particular, early proteins are thought to have been highly acidic, like nucleic acids, due to a scarcity of basic amino acids in the prebiotic context. Perhaps polyamines, the abiotic synthesis of which is simple, could have served as chemical chaperones for such primordial proteins? We replaced all lysines of an ancestral 60-residue helix-bundle protein with glutamate, resulting in a disordered protein with 21 glutamates in total. Polyamines efficiently induce folding of this hyperacidic protein at submillimolar concentrations, and their potency scaled with the number of amine groups. Compared to cations, polyamines were several orders of magnitude more potent than Na+, while Mg2+ and Ca2+ had an effect similar to that of a diamine, inducing folding at approximately seawater concentrations. We propose that (i) polyamines and dications may have had a role in promoting folding of early proteins devoid of basic residues and (ii) coil-helix transitions could be the basis of polyamine regulation in contemporary proteins.
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Affiliation(s)
- Dragana Despotović
- Department
of Biomolecular Sciences, Weizmann Institute
of Science, 7610001 Rehovot, Israel
| | - Liam M. Longo
- Department
of Biomolecular Sciences, Weizmann Institute
of Science, 7610001 Rehovot, Israel
- Earth-Life
Science Institute, Tokyo Institute of Technology, 152-8550 Tokyo, Japan
- Blue
Marble Space Institute of Science, Seattle, Washington 98154, United States
| | - Einav Aharon
- Department
of Biomolecular Sciences, Weizmann Institute
of Science, 7610001 Rehovot, Israel
| | - Amit Kahana
- Department
of Biomolecular Sciences, Weizmann Institute
of Science, 7610001 Rehovot, Israel
- Department
of Molecular Genetics, Weizmann Institute
of Science, 7610001 Rehovot, Israel
| | - Tali Scherf
- Department
of Chemical Research Support, Weizmann Institute
of Science, 7610001 Rehovot, Israel
| | - Ita Gruic-Sovulj
- Department
of Chemistry, Faculty of Science, University
of Zagreb, 10000 Zagreb, Croatia
| | - Dan S. Tawfik
- Department
of Biomolecular Sciences, Weizmann Institute
of Science, 7610001 Rehovot, Israel
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Muchowska KB, Varma SJ, Moran J. Nonenzymatic Metabolic Reactions and Life's Origins. Chem Rev 2020; 120:7708-7744. [PMID: 32687326 DOI: 10.1021/acs.chemrev.0c00191] [Citation(s) in RCA: 104] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Prebiotic chemistry aims to explain how the biochemistry of life as we know it came to be. Most efforts in this area have focused on provisioning compounds of importance to life by multistep synthetic routes that do not resemble biochemistry. However, gaining insight into why core metabolism uses the molecules, reactions, pathways, and overall organization that it does requires us to consider molecules not only as synthetic end goals. Equally important are the dynamic processes that build them up and break them down. This perspective has led many researchers to the hypothesis that the first stage of the origin of life began with the onset of a primitive nonenzymatic version of metabolism, initially catalyzed by naturally occurring minerals and metal ions. This view of life's origins has come to be known as "metabolism first". Continuity with modern metabolism would require a primitive version of metabolism to build and break down ketoacids, sugars, amino acids, and ribonucleotides in much the same way as the pathways that do it today. This review discusses metabolic pathways of relevance to the origin of life in a manner accessible to chemists, and summarizes experiments suggesting several pathways might have their roots in prebiotic chemistry. Finally, key remaining milestones for the protometabolic hypothesis are highlighted.
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Affiliation(s)
| | - Sreejith J Varma
- University of Strasbourg, CNRS, ISIS UMR 7006, 67000 Strasbourg, France
| | - Joseph Moran
- University of Strasbourg, CNRS, ISIS UMR 7006, 67000 Strasbourg, France
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