1
|
Corning PA. Cooperative genes in smart systems: Toward an inclusive new synthesis in evolution. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2024; 189:26-31. [PMID: 38593906 DOI: 10.1016/j.pbiomolbio.2024.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/03/2024] [Accepted: 04/03/2024] [Indexed: 04/11/2024]
Abstract
For more than half a century, biologist Julian Huxley's term, the "Modern Synthesis", has been used as a label for a model of biological evolution where genetic influences are viewed as a principal source of creativity and change. Over the years, as evidence has accumulated that there are many other, far more important factors at work in evolution, theoretical "compromises," such as the so-called "Extended Synthesis", have been proposed. This is no longer tenable. It is time to abandon the Modern Synthesis, and its doppelganger "The Selfish Gene". Here is the case for a new, multi-faceted, open-ended, "inclusive" evolutionary synthesis, where living systems themselves are recognized as purposeful (teleonomic) "agents" and cooperative effects (synergies) of various kinds are seen as all-important influences.
Collapse
Affiliation(s)
- Peter A Corning
- Institute for the Study of Complex Systems, 1390 158th Place NE #616, Bellevue, WA, 98008, USA.
| |
Collapse
|
2
|
Mrnjavac N, Wimmer JLE, Brabender M, Schwander L, Martin WF. The Moon-Forming Impact and the Autotrophic Origin of Life. Chempluschem 2023; 88:e202300270. [PMID: 37812146 PMCID: PMC7615287 DOI: 10.1002/cplu.202300270] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 09/29/2023] [Accepted: 10/03/2023] [Indexed: 10/10/2023]
Abstract
The Moon-forming impact vaporized part of Earth's mantle, and turned the rest into a magma ocean, from which carbon dioxide degassed into the atmosphere, where it stayed until water rained out to form the oceans. The rain dissolved CO2 and made it available to react with transition metal catalysts in the Earth's crust so as to ultimately generate the organic compounds that form the backbone of microbial metabolism. The Moon-forming impact was key in building a planet with the capacity to generate life in that it converted carbon on Earth into a homogeneous and accessible substrate for organic synthesis. Today all ecosystems, without exception, depend upon primary producers, organisms that fix CO2 . According to theories of autotrophic origin, it has always been that way, because autotrophic theories posit that the first forms of life generated all the molecules needed to build a cell from CO2 , forging a direct line of continuity between Earth's initial CO2 -rich atmosphere and the first microorganisms. By modern accounts these were chemolithoautotrophic archaea and bacteria that initially colonized the crust and still inhabit that environment today.
Collapse
Affiliation(s)
- Natalia Mrnjavac
- Department of Biology Institute for Molecular Evolution Heinrich Heine University Duesseldorf Universitaetsstr. 1, 40225 Düsseldorf (Germany)
| | - Jessica L. E. Wimmer
- Department of Biology Institute for Molecular Evolution Heinrich Heine University Duesseldorf Universitaetsstr. 1, 40225 Düsseldorf (Germany)
| | - Max Brabender
- Department of Biology Institute for Molecular Evolution Heinrich Heine University Duesseldorf Universitaetsstr. 1, 40225 Düsseldorf (Germany)
| | - Loraine Schwander
- Department of Biology Institute for Molecular Evolution Heinrich Heine University Duesseldorf Universitaetsstr. 1, 40225 Düsseldorf (Germany)
| | - William F. Martin
- Department of Biology Institute for Molecular Evolution Heinrich Heine University Duesseldorf Universitaetsstr. 1, 40225 Düsseldorf (Germany)
| |
Collapse
|
3
|
Schwander L, Brabender M, Mrnjavac N, Wimmer JLE, Preiner M, Martin WF. Serpentinization as the source of energy, electrons, organics, catalysts, nutrients and pH gradients for the origin of LUCA and life. Front Microbiol 2023; 14:1257597. [PMID: 37854333 PMCID: PMC10581274 DOI: 10.3389/fmicb.2023.1257597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 09/04/2023] [Indexed: 10/20/2023] Open
Abstract
Serpentinization in hydrothermal vents is central to some autotrophic theories for the origin of life because it generates compartments, reductants, catalysts and gradients. During the process of serpentinization, water circulates through hydrothermal systems in the crust where it oxidizes Fe (II) in ultramafic minerals to generate Fe (III) minerals and H2. Molecular hydrogen can, in turn, serve as a freely diffusible source of electrons for the reduction of CO2 to organic compounds, provided that suitable catalysts are present. Using catalysts that are naturally synthesized in hydrothermal vents during serpentinization H2 reduces CO2 to formate, acetate, pyruvate, and methane. These compounds represent the backbone of microbial carbon and energy metabolism in acetogens and methanogens, strictly anaerobic chemolithoautotrophs that use the acetyl-CoA pathway of CO2 fixation and that inhabit serpentinizing environments today. Serpentinization generates reduced carbon, nitrogen and - as newer findings suggest - reduced phosphorous compounds that were likely conducive to the origins process. In addition, it gives rise to inorganic microcompartments and proton gradients of the right polarity and of sufficient magnitude to support chemiosmotic ATP synthesis by the rotor-stator ATP synthase. This would help to explain why the principle of chemiosmotic energy harnessing is more conserved (older) than the machinery to generate ion gradients via pumping coupled to exergonic chemical reactions, which in the case of acetogens and methanogens involve H2-dependent CO2 reduction. Serpentinizing systems exist in terrestrial and deep ocean environments. On the early Earth they were probably more abundant than today. There is evidence that serpentinization once occurred on Mars and is likely still occurring on Saturn's icy moon Enceladus, providing a perspective on serpentinization as a source of reductants, catalysts and chemical disequilibrium for life on other worlds.
Collapse
Affiliation(s)
- Loraine Schwander
- Institute of Molecular Evolution, Biology Department, Math. -Nat. Faculty, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Max Brabender
- Institute of Molecular Evolution, Biology Department, Math. -Nat. Faculty, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Natalia Mrnjavac
- Institute of Molecular Evolution, Biology Department, Math. -Nat. Faculty, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Jessica L. E. Wimmer
- Institute of Molecular Evolution, Biology Department, Math. -Nat. Faculty, Heinrich-Heine-Universität, Düsseldorf, Germany
| | - Martina Preiner
- Microcosm Earth Center, Max Planck Institute for Terrestrial Microbiology and Philipps-Universität, Marburg, Germany
| | - William F. Martin
- Institute of Molecular Evolution, Biology Department, Math. -Nat. Faculty, Heinrich-Heine-Universität, Düsseldorf, Germany
| |
Collapse
|
4
|
van der Gulik PTS, Hoff WD, Speijer D. Renewing Linnaean taxonomy: a proposal to restructure the highest levels of the Natural System. Biol Rev Camb Philos Soc 2023; 98:584-602. [PMID: 36366773 DOI: 10.1111/brv.12920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 10/31/2022] [Accepted: 11/02/2022] [Indexed: 11/13/2022]
Abstract
During the last century enormous progress has been made in the understanding of biological diversity, involving a dramatic shift from macroscopic to microscopic organisms. The question now arises as to whether the Natural System introduced by Carl Linnaeus, which has served as the central system for organizing biological diversity, can accommodate the great expansion of diversity that has been discovered. Important discoveries regarding biological diversity have not been fully integrated into a formal, coherent taxonomic system. In addition, because of taxonomic challenges and conflicts, various proposals have been made to abandon key aspects of the Linnaean system. We review the current status of taxonomy of the living world, focussing on groups at the taxonomic level of phylum and above. We summarize the main arguments against and in favour of abandoning aspects of the Linnaean system. Based on these considerations, we conclude that retaining the Linnaean Natural System provides important advantages. We propose a relatively small number of amendments for extending this system, particularly to include the named rank of world (Latin alternative mundis) formally to include non-cellular entities (viruses), and the named rank of empire (Latin alternative imperium) to accommodate the depth of diversity in (unicellular) eukaryotes that has been uncovered. We argue that in the case of both the eukaryotic domain and the viruses the cladistic approach intrinsically fails. However, the resulting semi-cladistic system provides a productive way forward that can help resolve taxonomic challenges. The amendments proposed allow us to: (i) retain named taxonomic levels and the three-domain system, (ii) improve understanding of the main eukaryotic lineages, and (iii) incorporate viruses into the Natural System. Of note, the proposal described herein is intended to serve as the starting point for a broad scientific discussion regarding the modernization of the Linnaean system.
Collapse
Affiliation(s)
| | - Wouter D Hoff
- Department of Microbiology and Molecular Genetics and Department of Chemistry, Oklahoma State University, Stillwater, OK, 74078, USA
| | - David Speijer
- Department of Medical Biochemistry, AmsterdamUMC, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands
| |
Collapse
|
5
|
Speijer D. How mitochondria showcase evolutionary mechanisms and the importance of oxygen. Bioessays 2023; 45:e2300013. [PMID: 36965057 DOI: 10.1002/bies.202300013] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/10/2023] [Accepted: 03/14/2023] [Indexed: 03/27/2023]
Abstract
Darwinian evolution can be simply stated: natural selection of inherited variations increasing differential reproduction. However, formulated thus, links with biochemistry, cell biology, ecology, and population dynamics remain unclear. To understand interactive contributions of chance and selection, higher levels of biological organization (e.g., endosymbiosis), complexities of competing selection forces, and emerging biological novelties (such as eukaryotes or meiotic sex), we must analyze actual examples. Focusing on mitochondria, I will illuminate how biology makes sense of life's evolution, and the concepts involved. First, looking at the bacterium - mitochondrion transition: merging with an archaeon, it lost its independence, but played a decisive role in eukaryogenesis, as an extremely efficient aerobic ATP generator and internal ROS source. Second, surveying later mitochondrion adaptations and diversifications illustrates concepts such as constructive neutral evolution, dynamic interactions between endosymbionts and hosts, the contingency of life histories, and metabolic reprogramming. Without oxygen, mitochondria disappear; with (intermittent) oxygen diversification occurs in highly complex ways, especially upon (temporary) phototrophic substrate supply. These expositions show the Darwinian model to be a highly fruitful paradigm.
Collapse
Affiliation(s)
- Dave Speijer
- Department of Medical Biochemistry, Amsterdam UMC location University of Amsterdam, Amsterdam, the Netherlands
| |
Collapse
|
6
|
Panieri E, Pinho SA, Afonso GJM, Oliveira PJ, Cunha-Oliveira T, Saso L. NRF2 and Mitochondrial Function in Cancer and Cancer Stem Cells. Cells 2022; 11:cells11152401. [PMID: 35954245 PMCID: PMC9367715 DOI: 10.3390/cells11152401] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/01/2022] [Accepted: 08/02/2022] [Indexed: 12/21/2022] Open
Abstract
The NRF2–KEAP1 system is a fundamental component of the cellular response that controls a great variety of transcriptional targets that are mainly involved in the regulation of redox homeostasis and multiple cytoprotective mechanisms that confer adaptation to the stress conditions. The pleiotropic response orchestrated by NRF2 is particularly relevant in the context of oncogenic activation, wherein this transcription factor acts as a key driver of tumor progression and cancer cells’ resistance to treatment. For this reason, NRF2 has emerged as a promising therapeutic target in cancer cells, stimulating extensive research aimed at the identification of natural, as well as chemical, NRF2 inhibitors. Excitingly, the influence of NRF2 on cancer cells’ biology extends far beyond its mere antioxidant function and rather encompasses a functional crosstalk with the mitochondrial network that can influence crucial aspects of mitochondrial homeostasis, including biogenesis, oxidative phosphorylation, metabolic reprogramming, and mitophagy. In the present review, we summarize the current knowledge of the reciprocal interrelation between NRF2 and mitochondria, with a focus on malignant tumors and cancer stem cells.
Collapse
Affiliation(s)
- Emiliano Panieri
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, 00185 Rome, Italy
- Section of Hazardous Substances, Environmental Education and Training for the Technical Coordination of Management Activities (DGTEC), Italian Institute for Environmental Protection and Research, 00144 Rome, Italy
- Correspondence: (E.P.); (T.C.-O.); Tel.: +39-06-5007-2131 (E.P.); +351-231249195 (T.C.-O.)
| | - Sónia A. Pinho
- CNC—Center for Neuroscience and Cell Biology, CIBB—Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
- IIIUC—Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
- PhD Programme in Experimental Biology and Biomedicine (PDBEB), IIIUC—Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
| | - Gonçalo J. M. Afonso
- CNC—Center for Neuroscience and Cell Biology, CIBB—Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
- IIIUC—Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
- PhD Programme in Experimental Biology and Biomedicine (PDBEB), IIIUC—Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
| | - Paulo J. Oliveira
- CNC—Center for Neuroscience and Cell Biology, CIBB—Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
- IIIUC—Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
| | - Teresa Cunha-Oliveira
- CNC—Center for Neuroscience and Cell Biology, CIBB—Center for Innovative Biomedicine and Biotechnology, University of Coimbra, 3004-504 Coimbra, Portugal
- IIIUC—Institute for Interdisciplinary Research, University of Coimbra, 3030-789 Coimbra, Portugal
- Correspondence: (E.P.); (T.C.-O.); Tel.: +39-06-5007-2131 (E.P.); +351-231249195 (T.C.-O.)
| | - Luciano Saso
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, 00185 Rome, Italy
| |
Collapse
|
7
|
Bremer N, Tria FDK, Skejo J, Garg SG, Martin WF. Ancestral state reconstructions trace mitochondria but not phagocytosis to the last eukaryotic common ancestor. Genome Biol Evol 2022; 14:6596370. [PMID: 35642316 PMCID: PMC9185374 DOI: 10.1093/gbe/evac079] [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] [Accepted: 05/25/2022] [Indexed: 11/13/2022] Open
Abstract
Two main theories have been put forward to explain the origin of mitochondria in eukaryotes: phagotrophic engulfment (undigested food) and microbial symbiosis (physiological interactions). The two theories generate mutually exclusive predictions about the order in which mitochondria and phagocytosis arose. To discriminate the alternatives, we have employed ancestral state reconstructions (ASR) for phagocytosis as a trait, phagotrophy as a feeding habit, the presence of mitochondria, the presence of plastids, and the multinucleated organization across major eukaryotic lineages. To mitigate the bias introduced by assuming a particular eukaryotic phylogeny, we reconstructed the appearance of these traits across 1789 different rooted gene trees, each having species from opisthokonts, mycetozoa, hacrobia, excavate, archeplastida, and Stramenopiles, Alveolates and Rhizaria. The trees reflect conflicting relationships and different positions of the root. We employed a novel phylogenomic test that summarizes ASR across trees which reconstructs a last eukaryotic common ancestor that possessed mitochondria, was multinucleated, lacked plastids, and was non-phagotrophic as well as non-phagocytic. This indicates that both phagocytosis and phagotrophy arose subsequent to the origin of mitochondria, consistent with findings from comparative physiology. Furthermore, our ASRs uncovered multiple origins of phagocytosis and of phagotrophy across eukaryotes, indicating that, like wings in animals, these traits are useful but neither ancestral nor homologous across groups. The data indicate that mitochondria preceded the origin of phagocytosis, such that phagocytosis cannot have been the mechanism by which mitochondria were acquired.
Collapse
Affiliation(s)
- Nico Bremer
- Institute for Molecular Evolution, Heinrich Heine University Düsseldorf 40225 Düsseldorf, Germany
| | - Fernando D K Tria
- Institute for Molecular Evolution, Heinrich Heine University Düsseldorf 40225 Düsseldorf, Germany
| | - Josip Skejo
- Institute for Molecular Evolution, Heinrich Heine University Düsseldorf 40225 Düsseldorf, Germany
| | - Sriram G Garg
- Institute for Molecular Evolution, Heinrich Heine University Düsseldorf 40225 Düsseldorf, Germany
| | - William F Martin
- Institute for Molecular Evolution, Heinrich Heine University Düsseldorf 40225 Düsseldorf, Germany
| |
Collapse
|
8
|
Wimmer JLE, Xavier JC, Vieira ADN, Pereira DPH, Leidner J, Sousa FL, Kleinermanns K, Preiner M, Martin WF. Energy at Origins: Favorable Thermodynamics of Biosynthetic Reactions in the Last Universal Common Ancestor (LUCA). Front Microbiol 2021; 12:793664. [PMID: 34966373 PMCID: PMC8710812 DOI: 10.3389/fmicb.2021.793664] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 11/24/2021] [Indexed: 12/02/2022] Open
Abstract
Though all theories for the origin of life require a source of energy to promote primordial chemical reactions, the nature of energy that drove the emergence of metabolism at origins is still debated. We reasoned that evidence for the nature of energy at origins should be preserved in the biochemical reactions of life itself, whereby changes in free energy, ΔG, which determine whether a reaction can go forward or not, should help specify the source. By calculating values of ΔG across the conserved and universal core of 402 individual reactions that synthesize amino acids, nucleotides and cofactors from H2, CO2, NH3, H2S and phosphate in modern cells, we find that 95-97% of these reactions are exergonic (ΔG ≤ 0 kJ⋅mol-1) at pH 7-10 and 80-100°C under nonequilibrium conditions with H2 replacing biochemical reductants. While 23% of the core's reactions involve ATP hydrolysis, 77% are ATP-independent, thermodynamically driven by ΔG of reactions involving carbon bonds. We identified 174 reactions that are exergonic by -20 to -300 kJ⋅mol-1 at pH 9 and 80°C and that fall into ten reaction types: six pterin dependent alkyl or acyl transfers, ten S-adenosylmethionine dependent alkyl transfers, four acyl phosphate hydrolyses, 14 thioester hydrolyses, 30 decarboxylations, 35 ring closure reactions, 31 aromatic ring formations, and 44 carbon reductions by reduced nicotinamide, flavins, ferredoxin, or formate. The 402 reactions of the biosynthetic core trace to the last universal common ancestor (LUCA), and reveal that synthesis of LUCA's chemical constituents required no external energy inputs such as electric discharge, UV-light or phosphide minerals. The biosynthetic reactions of LUCA uncover a natural thermodynamic tendency of metabolism to unfold from energy released by reactions of H2, CO2, NH3, H2S, and phosphate.
Collapse
Affiliation(s)
- Jessica L. E. Wimmer
- Department of Biology, Institute of Molecular Evolution, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Joana C. Xavier
- Department of Biology, Institute of Molecular Evolution, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Andrey d. N. Vieira
- Department of Biology, Institute of Molecular Evolution, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Delfina P. H. Pereira
- Department of Biology, Institute of Molecular Evolution, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Jacqueline Leidner
- Department of Biology, Institute of Molecular Evolution, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Filipa L. Sousa
- Department of Functional and Evolutionary Ecology, University of Vienna, Vienna, Austria
| | - Karl Kleinermanns
- Department of Chemistry, Institute of Physical Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Martina Preiner
- Department of Biology, Institute of Molecular Evolution, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - William F. Martin
- Department of Biology, Institute of Molecular Evolution, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| |
Collapse
|
9
|
Skejo J, Garg SG, Gould SB, Hendriksen M, Tria FDK, Bremer N, Franjević D, Blackstone NW, Martin WF. Evidence for a Syncytial Origin of Eukaryotes from Ancestral State Reconstruction. Genome Biol Evol 2021; 13:evab096. [PMID: 33963405 PMCID: PMC8290118 DOI: 10.1093/gbe/evab096] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/28/2021] [Indexed: 12/11/2022] Open
Abstract
Modern accounts of eukaryogenesis entail an endosymbiotic encounter between an archaeal host and a proteobacterial endosymbiont, with subsequent evolution giving rise to a unicell possessing a single nucleus and mitochondria. The mononucleate state of the last eukaryotic common ancestor (LECA) is seldom, if ever, questioned, even though cells harboring multiple (syncytia, coenocytes, and polykaryons) are surprisingly common across eukaryotic supergroups. Here, we present a survey of multinucleated forms. Ancestral character state reconstruction for representatives of 106 eukaryotic taxa using 16 different possible roots and supergroup sister relationships, indicate that LECA, in addition to being mitochondriate, sexual, and meiotic, was multinucleate. LECA exhibited closed mitosis, which is the rule for modern syncytial forms, shedding light on the mechanics of its chromosome segregation. A simple mathematical model shows that within LECA's multinucleate cytosol, relationships among mitochondria and nuclei were neither one-to-one, nor one-to-many, but many-to-many, placing mitonuclear interactions and cytonuclear compatibility at the evolutionary base of eukaryotic cell origin. Within a syncytium, individual nuclei and individual mitochondria function as the initial lower-level evolutionary units of selection, as opposed to individual cells, during eukaryogenesis. Nuclei within a syncytium rescue each other's lethal mutations, thereby postponing selection for viable nuclei and cytonuclear compatibility to the generation of spores, buffering transitional bottlenecks at eukaryogenesis. The prokaryote-to-eukaryote transition is traditionally thought to have left no intermediates, yet if eukaryogenesis proceeded via a syncytial common ancestor, intermediate forms have persisted to the present throughout the eukaryotic tree as syncytia but have so far gone unrecognized.
Collapse
Affiliation(s)
- Josip Skejo
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
- Faculty of Science, Division of Zoology, Department of Biology, University of Zagreb, Evolution Lab, Zagreb, Croatia
| | - Sriram G Garg
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Sven B Gould
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Michael Hendriksen
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Fernando D K Tria
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Nico Bremer
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Damjan Franjević
- Faculty of Science, Division of Zoology, Department of Biology, University of Zagreb, Evolution Lab, Zagreb, Croatia
| | - Neil W Blackstone
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL, USA
| | - William F Martin
- Institute for Molecular Evolution, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| |
Collapse
|
10
|
Sato N. Are Cyanobacteria an Ancestor of Chloroplasts or Just One of the Gene Donors for Plants and Algae? Genes (Basel) 2021; 12:genes12060823. [PMID: 34071987 PMCID: PMC8227023 DOI: 10.3390/genes12060823] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Revised: 05/08/2021] [Accepted: 05/25/2021] [Indexed: 12/04/2022] Open
Abstract
Chloroplasts of plants and algae are currently believed to originate from a cyanobacterial endosymbiont, mainly based on the shared proteins involved in the oxygenic photosynthesis and gene expression system. The phylogenetic relationship between the chloroplast and cyanobacterial genomes was important evidence for the notion that chloroplasts originated from cyanobacterial endosymbiosis. However, studies in the post-genomic era revealed that various substances (glycolipids, peptidoglycan, etc.) shared by cyanobacteria and chloroplasts are synthesized by different pathways or phylogenetically unrelated enzymes. Membranes and genomes are essential components of a cell (or an organelle), but the origins of these turned out to be different. Besides, phylogenetic trees of chloroplast-encoded genes suggest an alternative possibility that chloroplast genes could be acquired from at least three different lineages of cyanobacteria. We have to seriously examine that the chloroplast genome might be chimeric due to various independent gene flows from cyanobacteria. Chloroplast formation could be more complex than a single event of cyanobacterial endosymbiosis. I present the “host-directed chloroplast formation” hypothesis, in which the eukaryotic host cell that had acquired glycolipid synthesis genes as an adaptation to phosphate limitation facilitated chloroplast formation by providing glycolipid-based membranes (pre-adaptation). The origins of the membranes and the genome could be different, and the origin of the genome could be complex.
Collapse
Affiliation(s)
- Naoki Sato
- Graduate School of Arts and Sciences, University of Tokyo, Meguro-ku, Tokyo 153-8902, Japan
| |
Collapse
|
11
|
To What Inanimate Matter Are We Most Closely Related and Does the Origin of Life Harbor Meaning? PHILOSOPHIES 2021. [DOI: 10.3390/philosophies6020033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The question concerning the meaning of life is important, but it immediately confronts the present authors with insurmountable obstacles from a philosophical standpoint, as it would require us to define not only what we hold to be life, but what we hold to be meaning in addition, requiring us to do both in a properly researched context. We unconditionally surrender to that challenge. Instead, we offer a vernacular, armchair approach to life’s origin and meaning, with some layman’s thoughts on the meaning of origins as viewed from the biologist’s standpoint. One can observe that biologists generally approach the concept of biological meaning in the context of evolution. This is the basis for the broad resonance behind Dobzhansky’s appraisal that “Nothing in biology makes sense except in the light of evolution”. Biologists try to understand living things in the historical context of how they arose, without giving much thought to the definition of what life or living things are, which for a biologist is usually not an interesting question in the practical context of daily dealings with organisms. Do humans generally understand life’s meaning in the context of history? If we consider the problem of life’s origin, the question of what constitutes a living thing becomes somewhat more acute for the biologist, though not more answerable, because it is inescapable that there was a time when there were no organisms on Earth, followed by a time when there were, the latter time having persisted in continuity to the present. This raises the question of where, in that transition, chemicals on Earth became alive, requiring, in turn, a set of premises for how life arose in order to conceptualize the problem in relation to organisms we know today, including ourselves, which brings us to the point of this paper: In the same way that cultural narratives for origins always start with a setting, scientific narratives for origins also always start with a setting, a place on Earth or elsewhere where we can imagine what happened for the sake of structuring both the problem and the narrative for its solution. This raises the question of whether scientific origins settings convey meaning to humans in that they suggest to us from what kind of place and what kinds of chemicals we are descended, that is, to which inanimate things we are most closely related.
Collapse
|
12
|
Mikhailovsky G, Gordon R, Igamberdiev AU. Editorial: Symbiogenesis and progressive evolution. Biosystems 2021; 206:104429. [PMID: 33864879 DOI: 10.1016/j.biosystems.2021.104429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Richard Gordon
- Gulf Specimen Marine Laboratory, Panacea, FL, 32346, United States; C.S. Mott Center for Human Growth & Development, Department of Obstetrics & Gynecology, Wayne State University, Detroit, MI, United States.
| | - Abir U Igamberdiev
- Department of Biology, Memorial University of Newfoundland, St. John's, NL, A1B 3X9, Canada.
| |
Collapse
|
13
|
Lazcano A, Peretó J. Prokaryotic symbiotic consortia and the origin of nucleated cells: A critical review of Lynn Margulis hypothesis. Biosystems 2021; 204:104408. [PMID: 33744400 DOI: 10.1016/j.biosystems.2021.104408] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 03/11/2021] [Indexed: 12/17/2022]
Abstract
The publication in the late 1960s of Lynn Margulis endosymbiotic proposal is a scientific milestone that brought to the fore of evolutionary discussions the issue of the origin of nucleated cells. Although it is true that the times were ripe, the timely publication of Lynn Margulis' original paper was the product of an intellectually bold 29-years old scientist, who based on the critical analysis of the available scientific information produced an all-encompassing, sophisticated narrative scheme on the origin of eukaryotic cells as a result of the evolution of prokaryotic consortia and, in bold intellectual stroke, put it all in the context of planetary evolution. A critical historical reassessment of her original proposal demonstrates that her hypothesis was not a simple archival outline of past schemes, but a renewed historical narrative of prokaryotic evolution and the role of endosymbiosis in the origin of eukaryotes. Although it is now accepted that the closest bacterial relatives of mitochondria and plastids are α-proteobacteria and cyanobacteria, respectively, comparative genomics demonstrates the mosaic character of the organelle genomes. The available evidence has completely refuted Margulis' proposal of an exogenous origin for eukaryotic flagella, the (9 + 2) basal bodies, and centromeres, but we discuss in detail the reasons that led her to devote considerable efforts to argue for a symbiotic origin of the eukaryotic motility. An analysis of the arguments successfully employed by Margulis in her persuasive advocacy of endosymbiosis, combined with the discussions of her flaws and the scientific atmosphere during the period in which she formulated her proposals, are critical for a proper appraisal of the historical conditions that shaped her theory and its acceptance.
Collapse
Affiliation(s)
- Antonio Lazcano
- Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico; Miembro de El Colegio Nacional, Mexico.
| | - Juli Peretó
- Department of Biochemistry and Molecular Biology, Universitat de València, C. Dr. Moliner 50, 46100, Burjassot, Spain; Institute for Integrative Systems Biology (I(2)SysBio), Universitat de València-CSIC, C. José Beltrán 2, 46980, Paterna, Spain.
| |
Collapse
|
14
|
The Autotrophic Core: An Ancient Network of 404 Reactions Converts H 2, CO 2, and NH 3 into Amino Acids, Bases, and Cofactors. Microorganisms 2021; 9:microorganisms9020458. [PMID: 33672143 PMCID: PMC7926472 DOI: 10.3390/microorganisms9020458] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 02/11/2021] [Accepted: 02/19/2021] [Indexed: 01/03/2023] Open
Abstract
The metabolism of cells contains evidence reflecting the process by which they arose. Here, we have identified the ancient core of autotrophic metabolism encompassing 404 reactions that comprise the reaction network from H2, CO2, and ammonia (NH3) to amino acids, nucleic acid monomers, and the 19 cofactors required for their synthesis. Water is the most common reactant in the autotrophic core, indicating that the core arose in an aqueous environment. Seventy-seven core reactions involve the hydrolysis of high-energy phosphate bonds, furthermore suggesting the presence of a non-enzymatic and highly exergonic chemical reaction capable of continuously synthesizing activated phosphate bonds. CO2 is the most common carbon-containing compound in the core. An abundance of NADH and NADPH-dependent redox reactions in the autotrophic core, the central role of CO2, and the circumstance that the core’s main products are far more reduced than CO2 indicate that the core arose in a highly reducing environment. The chemical reactions of the autotrophic core suggest that it arose from H2, inorganic carbon, and NH3 in an aqueous environment marked by highly reducing and continuously far from equilibrium conditions. Such conditions are very similar to those found in serpentinizing hydrothermal systems.
Collapse
|
15
|
From Empedocles to Symbiogenetics: Lynn Margulis's revolutionary influence on evolutionary biology. Biosystems 2021; 204:104386. [PMID: 33621579 DOI: 10.1016/j.biosystems.2021.104386] [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] [Received: 02/12/2021] [Accepted: 02/12/2021] [Indexed: 02/07/2023]
Abstract
As a primary expositor of the work of Lynn Margulis collaborating with her over thirty years on over thirty books and forty articles, scientific and popular, I attempt here to summarize her unique and lasting influence on evolutionary biology. Describing life on Earth as the multi-billion-year evolution of microbial communities, from prokaryotes maintaining Earth's atmosphere away from thermodynamic equilibrium to all eukaryotes as polygenomic beings, Margulis's interdisciplinary work has deeply influenced multiple fields including systematics, theories of the evolution of metabolism, paleobiology, and biogeochemistry. Overturning the neo-Darwinist narrative that speciation almost always occurs by the gradual accumulation of random mutations, Margulis's work revives a discarded philosophical speculation of the pre-Socratic Empedocles, who suggested that Earth's early beings both merged and differentially reproduced (were naturally selected); a speculation that was rejected by Aristotle probably because it smacked of mythological chimeras that had no place in observational biology, and later by Charles Darwin, who mentioned Aristotle's rejection of Empedocles to show that he knew of but did not accept natural selection, thus helping lay his own claim to its own proper scientific presentation in a Victorian culture whose thinking of origins was dominated not by Greek mythology but Christian special creation. Margulis's curiosity-driven science, collaborative work ethic, status as a woman, embrace of novelty, philosophical stance, current status of her theories, and the proposal for a new science of symbiogenetics are among the topics examined.
Collapse
|
16
|
Grabovich MY, Gureeva MV, Dubinina GA. The role of the "Thiodendron" consortium in postulating the karyomastigont chimaera of the endosymbiosis theory by Lynn Margulis. Biosystems 2020; 200:104322. [PMID: 33309968 DOI: 10.1016/j.biosystems.2020.104322] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/03/2020] [Accepted: 12/03/2020] [Indexed: 11/18/2022]
Abstract
The endosymbiosis theory of the origin of eukaryotic cell was first proposed more than a hundred years ago. In the second half of the 20th century, Lynn Margulis suggested a new interpretation of the origin of the nucleus in modern eukaryotes. The background was the study of the consortium "Thiodendron", a symbiotic bacterial community, which includes anaerobic aerotolerant motile spirochaetes and sulfidogenic bacteria (sulfidogens) of vibrioid form with a fermentation type of metabolism. Spirochaetes supply sulfidogens with metabolites (pyruvate and, probably, organic nitrogenous products of cell lysis) and get hydrogen sulfide from sulfidogens that helps to maintain a low redox potential. At low oxygen concentrations, spirochaetes are able to assimilate glucose more efficiently. Margulis hypothesized about the symbiotic origin of the nucleus by adding the bacterium Spirochaeta to the Thermoplasma-like archaea. She considered the "Thiodendron"-like consortium to be an intermediate stage in evolution. According to Margulis, the conversion of carbohydrates and the oxidation of Н2S to S0 by the bacterium provided the archaea with electron acceptors for anaerobic respiration, as shown for modern thermoplasmas and products saturated with carbon. The use of carbon sources increased by attaching the floating bacterium to the archaea. More efficient microaerobic oxidation of glucose pre-adapted the spirochaetes for association with Thermoplasma. However, modern "Thiodendron"-like consortia are not in stable symbiosis and a sulfidogenic component of the consortium is capable for fermentation, rather than anaerobic respiration, which makes the theory by Margulis disputable.
Collapse
Affiliation(s)
- Margarita Y Grabovich
- Department of Biochemistry and Cell Physiology, Voronezh State University, Voronezh, 394018, Russia.
| | - Maria V Gureeva
- Department of Biochemistry and Cell Physiology, Voronezh State University, Voronezh, 394018, Russia
| | - Galina A Dubinina
- Federal State Institution 'Federal Research Centre "Fundamentals of Biotechnology" of the Russian Academy of Sciences', 117312 Moscow, Russia
| |
Collapse
|
17
|
Agafonov VA, Negrobov VV, Igamberdiev AU. Symbiogenesis as a driving force of evolution: The legacy of Boris Kozo-Polyansky. Biosystems 2020; 199:104302. [PMID: 33227379 DOI: 10.1016/j.biosystems.2020.104302] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/17/2020] [Accepted: 11/18/2020] [Indexed: 02/06/2023]
Abstract
We analyze evolutionary views of Boris Kozo-Polyansky (1890-1957) who was the first who formulated the symbiotic theory of evolution as a concept in his book, Symbiogenesis: A New Principle of Evolution (1924). Later, starting from 1967, Lynn Margulis independently formulated and further developed the concept of symbiogenesis. Although the ideas on the symbiotic origin of chloroplasts and mitochondria appeared earlier, the book of Kozo-Polyansky presented symbiogenesis as the main factor of complexification in the course of evolution, not only in relation to the origin of eukaryotic cell. Kozo-Polyansky incorporated the ideas of symbiogenesis into a broader paradigm that anticipated the important concepts of the modern Extended Evolutionary Synthesis such as the idea of net of life, the evolutionary role of apoptosis, the ideas of punctuated equilibrium, and the concept of metasystem transition.
Collapse
Affiliation(s)
- Vladimir A Agafonov
- Department of Botany and Mycology, Voronezh State University, Voronezh, 394006, Russia.
| | - Vladimir V Negrobov
- Department of Botany and Mycology, Voronezh State University, Voronezh, 394006, Russia.
| | - Abir U Igamberdiev
- Department of Biology, Memorial University of Newfoundland, St. John's, NL, A1B 3X9, Canada.
| |
Collapse
|