1
|
Cohen ZR, Todd ZR, Wogan N, Black RA, Keller SL, Catling DC. Plausible Sources of Membrane-Forming Fatty Acids on the Early Earth: A Review of the Literature and an Estimation of Amounts. ACS EARTH & SPACE CHEMISTRY 2023; 7:11-27. [PMID: 36704178 PMCID: PMC9869395 DOI: 10.1021/acsearthspacechem.2c00168%20] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 10/18/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
The first cells were plausibly bounded by membranes assembled from fatty acids with at least 8 carbons. Although the presence of fatty acids on the early Earth is widely assumed within the astrobiology community, there is no consensus regarding their origin and abundance. In this Review, we highlight three possible sources of fatty acids: (1) delivery by carbonaceous meteorites, (2) synthesis on metals delivered by impactors, and (3) electrochemical synthesis by spark discharges. We also discuss fatty acid synthesis by UV or particle irradiation, gas-phase ion-molecule reactions, and aqueous redox reactions. We compare estimates for the total mass of fatty acids supplied to Earth by each source during the Hadean eon after an extremely massive asteroid impact that would have reset Earth's fatty acid inventory. We find that synthesis on iron-rich surfaces derived from the massive impactor in contact with an impact-generated reducing atmosphere could have contributed ∼102 times more total mass of fatty acids than subsequent delivery by either carbonaceous meteorites or electrochemical synthesis. Additionally, we estimate that a single carbonaceous meteorite would not deliver a high enough concentration of fatty acids (∼15 mM for decanoic acid) into an existing body of water on the Earth's surface to spontaneously form membranes unless the fatty acids were further concentrated by another mechanism, such as subsequent evaporation of the water. Our estimates rely heavily on various assumptions, leading to significant uncertainties; nevertheless, these estimates provide rough order-of-magnitude comparisons of various sources of fatty acids on the early Earth. We also suggest specific experiments to improve future estimates. Our calculations support the view that fatty acids would have been available on the early Earth. Further investigation is needed to assess the mechanisms by which fatty acids could have been concentrated sufficiently to assemble into membranes during the origin of life.
Collapse
Affiliation(s)
- Zachary R. Cohen
- Department
of Chemistry, Department of Earth and Space Sciences, and Astrobiology Program, University of Washington, Seattle, Washington 98195, United States
| | - Zoe R. Todd
- Department
of Chemistry, Department of Earth and Space Sciences, and Astrobiology Program, University of Washington, Seattle, Washington 98195, United States
| | - Nicholas Wogan
- Department
of Chemistry, Department of Earth and Space Sciences, and Astrobiology Program, University of Washington, Seattle, Washington 98195, United States
| | - Roy A. Black
- Department
of Chemistry, Department of Earth and Space Sciences, and Astrobiology Program, University of Washington, Seattle, Washington 98195, United States
| | - Sarah L. Keller
- Department
of Chemistry, Department of Earth and Space Sciences, and Astrobiology Program, University of Washington, Seattle, Washington 98195, United States
| | - David C. Catling
- Department
of Chemistry, Department of Earth and Space Sciences, and Astrobiology Program, University of Washington, Seattle, Washington 98195, United States
| |
Collapse
|
2
|
Cohen ZR, Todd ZR, Wogan N, Black RA, Keller SL, Catling DC. Plausible Sources of Membrane-Forming Fatty Acids on the Early Earth: A Review of the Literature and an Estimation of Amounts. ACS EARTH & SPACE CHEMISTRY 2023; 7:11-27. [PMID: 36704178 PMCID: PMC9869395 DOI: 10.1021/acsearthspacechem.2c00168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 10/18/2022] [Accepted: 10/24/2022] [Indexed: 06/18/2023]
Abstract
The first cells were plausibly bounded by membranes assembled from fatty acids with at least 8 carbons. Although the presence of fatty acids on the early Earth is widely assumed within the astrobiology community, there is no consensus regarding their origin and abundance. In this Review, we highlight three possible sources of fatty acids: (1) delivery by carbonaceous meteorites, (2) synthesis on metals delivered by impactors, and (3) electrochemical synthesis by spark discharges. We also discuss fatty acid synthesis by UV or particle irradiation, gas-phase ion-molecule reactions, and aqueous redox reactions. We compare estimates for the total mass of fatty acids supplied to Earth by each source during the Hadean eon after an extremely massive asteroid impact that would have reset Earth's fatty acid inventory. We find that synthesis on iron-rich surfaces derived from the massive impactor in contact with an impact-generated reducing atmosphere could have contributed ∼102 times more total mass of fatty acids than subsequent delivery by either carbonaceous meteorites or electrochemical synthesis. Additionally, we estimate that a single carbonaceous meteorite would not deliver a high enough concentration of fatty acids (∼15 mM for decanoic acid) into an existing body of water on the Earth's surface to spontaneously form membranes unless the fatty acids were further concentrated by another mechanism, such as subsequent evaporation of the water. Our estimates rely heavily on various assumptions, leading to significant uncertainties; nevertheless, these estimates provide rough order-of-magnitude comparisons of various sources of fatty acids on the early Earth. We also suggest specific experiments to improve future estimates. Our calculations support the view that fatty acids would have been available on the early Earth. Further investigation is needed to assess the mechanisms by which fatty acids could have been concentrated sufficiently to assemble into membranes during the origin of life.
Collapse
Affiliation(s)
- Zachary R. Cohen
- Department
of Chemistry, Department of Earth and Space Sciences, and Astrobiology Program, University of Washington, Seattle, Washington 98195, United States
| | - Zoe R. Todd
- Department
of Chemistry, Department of Earth and Space Sciences, and Astrobiology Program, University of Washington, Seattle, Washington 98195, United States
| | - Nicholas Wogan
- Department
of Chemistry, Department of Earth and Space Sciences, and Astrobiology Program, University of Washington, Seattle, Washington 98195, United States
| | - Roy A. Black
- Department
of Chemistry, Department of Earth and Space Sciences, and Astrobiology Program, University of Washington, Seattle, Washington 98195, United States
| | - Sarah L. Keller
- Department
of Chemistry, Department of Earth and Space Sciences, and Astrobiology Program, University of Washington, Seattle, Washington 98195, United States
| | - David C. Catling
- Department
of Chemistry, Department of Earth and Space Sciences, and Astrobiology Program, University of Washington, Seattle, Washington 98195, United States
| |
Collapse
|
3
|
Nader S, Baccouche A, Connolly F, Abou-Ghanem M, Styler SA, Lewis JD, Pink D, Mansy SS. Model Atmospheric Aerosols Convert to Vesicles upon Entry into Aqueous Solution. ACS EARTH & SPACE CHEMISTRY 2023; 7:252-259. [PMID: 36704180 PMCID: PMC9869892 DOI: 10.1021/acsearthspacechem.2c00328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 12/08/2022] [Accepted: 12/09/2022] [Indexed: 06/18/2023]
Abstract
Aerosols are abundant on the Earth and likely played a role in prebiotic chemistry. Aerosol particles coagulate, divide, and sample a wide variety of conditions conducive to synthesis. While much work has centered on the generation of aerosols and their chemistry, little effort has been expended on their fate after settling. Here, using a laboratory model, we show that aqueous aerosols transform into cell-sized protocellular structures upon entry into aqueous solution containing lipid. Such processes provide for a heretofore unexplored pathway for the assembly of the building blocks of life from disparate geochemical regions within cell-like vesicles with a lipid bilayer in a manner that does not lead to dilution. The efficiency of aerosol to vesicle transformation is high with prebiotically plausible lipids, such as decanoic acid and decanol, that were previously shown to be capable of forming growing and dividing vesicles. The high transformation efficiency with 10-carbon lipids in landing solutions is consistent with the surface properties and dynamics of short-chain lipids. Similar processes may be operative today as fatty acids are common constituents of both contemporary aerosols and the sea. Our work highlights a new pathway that may have facilitated the emergence of the Earth's first cells.
Collapse
Affiliation(s)
- Serge Nader
- Department
of Chemistry, University of Alberta, Edmonton, AlbertaT6G 2N4, Canada
| | - Alexandre Baccouche
- Department
of Chemistry, University of Alberta, Edmonton, AlbertaT6G 2N4, Canada
| | - Fiona Connolly
- Department
of Chemistry, University of Alberta, Edmonton, AlbertaT6G 2N4, Canada
| | - Maya Abou-Ghanem
- Department
of Chemistry, University of Alberta, Edmonton, AlbertaT6G 2N4, Canada
| | - Sarah A. Styler
- Department
of Chemistry, University of Alberta, Edmonton, AlbertaT6G 2N4, Canada
| | - John D. Lewis
- Department
of Oncology, University of Alberta, Edmonton, AlbertaT6G 2E1, Canada
| | - Desmond Pink
- Nanostics
Inc., Edmonton, AlbertaT5J 4P6, Canada
| | - Sheref S. Mansy
- Department
of Chemistry, University of Alberta, Edmonton, AlbertaT6G 2N4, Canada
| |
Collapse
|
4
|
Alkanes as Membrane Regulators of the Response of Early Membranes to Extreme Temperatures. Life (Basel) 2022; 12:life12030445. [PMID: 35330196 PMCID: PMC8949167 DOI: 10.3390/life12030445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 03/02/2022] [Accepted: 03/10/2022] [Indexed: 11/16/2022] Open
Abstract
One of the first steps in the origin of life was the formation of a membrane, a physical boundary that allowed the retention of molecules in concentrated solutions. The proto-membrane was likely formed by self-assembly of simple readily available amphiphiles, such as short-chain fatty acids and alcohols. In the commonly accepted scenario that life originated near hydrothermal systems, how these very simple membrane bilayers could be stable enough in time remains a debated issue. We used various complementary techniques such as dynamic light scattering, small angle neutron scattering, neutron spin-echo spectroscopy, and Fourier-transform infrared spectroscopy to explore the stability of a novel protomembrane system in which the insertion of alkanes in the midplane is proposed to shift membrane stability to higher temperatures, pH, and hydrostatic pressures. We show that, in absence of alkanes, protomembranes transition into lipid droplets when temperature increases; while in presence of alkanes, membranes persist for longer times in a concentration-dependent manner. Proto-membranes containing alkanes are stable at higher temperatures and for longer times, have a higher bending rigidity, and can revert more easily to their initial state upon temperature variations. Hence, the presence of membrane intercalating alkanes could explain how the first membranes could resist the harsh and changing environment of the hydrothermal systems. Furthermore, modulating the quantity of alkanes in the first membranes appears as a possible strategy to adapt the proto-membrane behavior according to temperature fluctuations, and it offers a first glimpse into the evolution of the first membranes.
Collapse
|
5
|
Kloprogge JT(T, Hartman H. Clays and the Origin of Life: The Experiments. Life (Basel) 2022; 12:life12020259. [PMID: 35207546 PMCID: PMC8880559 DOI: 10.3390/life12020259] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/08/2022] [Accepted: 02/01/2022] [Indexed: 12/15/2022] Open
Abstract
There are three groups of scientists dominating the search for the origin of life: the organic chemists (the Soup), the molecular biologists (RNA world), and the inorganic chemists (metabolism and transient-state metal ions), all of which have experimental adjuncts. It is time for Clays and the Origin of Life to have its experimental adjunct. The clay data coming from Mars and carbonaceous chondrites have necessitated a review of the role that clays played in the origin of life on Earth. The data from Mars have suggested that Fe-clays such as nontronite, ferrous saponites, and several other clays were formed on early Mars when it had sufficient water. This raised the question of the possible role that these clays may have played in the origin of life on Mars. This has put clays front and center in the studies on the origin of life not only on Mars but also here on Earth. One of the major questions is: What was the catalytic role of Fe-clays in the origin and development of metabolism here on Earth? First, there is the recent finding of a chiral amino acid (isovaline) that formed on the surface of a clay mineral on several carbonaceous chondrites. This points to the formation of amino acids on the surface of clay minerals on carbonaceous chondrites from simpler molecules, e.g., CO2, NH3, and HCN. Additionally, there is the catalytic role of small organic molecules, such as dicarboxylic acids and amino acids found on carbonaceous chondrites, in the formation of Fe-clays themselves. Amino acids and nucleotides adsorb on clay surfaces on Earth and subsequently polymerize. All of these observations and more must be subjected to strict experimental analysis. This review provides an overview of what has happened and is now happening in the experimental clay world related to the origin of life. The emphasis is on smectite-group clay minerals, such as montmorillonite and nontronite.
Collapse
Affiliation(s)
- Jacob Teunis (Theo) Kloprogge
- School of Earth and Environmental Sciences, The University of Queensland, Brisbane, QLD 4072, Australia
- Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, Miagao 5023, Philippines
- Correspondence: (J.T.K.); (H.H.)
| | - Hyman Hartman
- Department of Earth Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
- Correspondence: (J.T.K.); (H.H.)
| |
Collapse
|
6
|
Gaylor MO, Miro P, Vlaisavljevich B, Kondage AAS, Barge LM, Omran A, Videau P, Swenson VA, Leinen LJ, Fitch NW, Cole KL, Stone C, Drummond SM, Rageth K, Dewitt LR, González Henao S, Karanauskus V. Plausible Emergence and Self Assembly of a Primitive Phospholipid from Reduced Phosphorus on the Primordial Earth. ORIGINS LIFE EVOL B 2021; 51:185-213. [PMID: 34279769 DOI: 10.1007/s11084-021-09613-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 06/19/2021] [Indexed: 11/28/2022]
Abstract
How life arose on the primitive Earth is one of the biggest questions in science. Biomolecular emergence scenarios have proliferated in the literature but accounting for the ubiquity of oxidized (+ 5) phosphate (PO43-) in extant biochemistries has been challenging due to the dearth of phosphate and molecular oxygen on the primordial Earth. A compelling body of work suggests that exogenous schreibersite ((Fe,Ni)3P) was delivered to Earth via meteorite impacts during the Heavy Bombardment (ca. 4.1-3.8 Gya) and there converted to reduced P oxyanions (e.g., phosphite (HPO32-) and hypophosphite (H2PO2-)) and phosphonates. Inspired by this idea, we review the relevant literature to deduce a plausible reduced phospholipid analog of modern phosphatidylcholines that could have emerged in a primordial hydrothermal setting. A shallow alkaline lacustrine basin underlain by active hydrothermal fissures and meteoritic schreibersite-, clay-, and metal-enriched sediments is envisioned. The water column is laden with known and putative primordial hydrothermal reagents. Small system dimensions and thermal- and UV-driven evaporation further concentrate chemical precursors. We hypothesize that a reduced phospholipid arises from Fischer-Tropsch-type (FTT) production of a C8 alkanoic acid, which condenses with an organophosphinate (derived from schreibersite corrosion to hypophosphite with subsequent methylation/oxidation), to yield a reduced protophospholipid. This then condenses with an α-amino nitrile (derived from Strecker-type reactions) to form the polar head. Preliminary modeling results indicate that reduced phospholipids do not aggregate rapidly; however, single layer micelles are stable up to aggregates with approximately 100 molecules.
Collapse
Affiliation(s)
- Michael O Gaylor
- Department of Chemistry, Dakota State University, Madison, SD, 57042, USA.
| | - Pere Miro
- Department of Chemistry, University of South Dakota, Vermillion, SD, 57069, USA
| | - Bess Vlaisavljevich
- Department of Chemistry, University of South Dakota, Vermillion, SD, 57069, USA
| | | | - Laura M Barge
- NASA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, 91109, USA
| | - Arthur Omran
- School of Geosciences, University of South Florida, Tampa, FL, 33620, USA.,Department of Chemistry, University of North Florida, Jacksonville, FL, 32224, USA
| | - Patrick Videau
- Department of Biology, Southern Oregon University, Ashland, OR, 97520, USA.,Bayer Crop Science, Chesterfield, MO, 63017, USA
| | - Vaille A Swenson
- Department of Chemistry, Dakota State University, Madison, SD, 57042, USA.,Department of Molecular Medicine, Mayo Clinic, Rochester, MN, 55905, USA
| | - Lucas J Leinen
- Department of Chemistry, Dakota State University, Madison, SD, 57042, USA
| | - Nathaniel W Fitch
- Department of Chemistry, Dakota State University, Madison, SD, 57042, USA
| | - Krista L Cole
- Department of Chemistry, Dakota State University, Madison, SD, 57042, USA
| | - Chris Stone
- Department of Biology, Southern Oregon University, Ashland, OR, 97520, USA
| | - Samuel M Drummond
- Department of Chemistry, Dakota State University, Madison, SD, 57042, USA
| | - Kayli Rageth
- Department of Chemistry, Dakota State University, Madison, SD, 57042, USA
| | - Lillian R Dewitt
- Department of Chemistry, Dakota State University, Madison, SD, 57042, USA
| | | | | |
Collapse
|
7
|
Smith HH, Hyde AS, Simkus DN, Libby E, Maurer SE, Graham HV, Kempes CP, Sherwood Lollar B, Chou L, Ellington AD, Fricke GM, Girguis PR, Grefenstette NM, Pozarycki CI, House CH, Johnson SS. The Grayness of the Origin of Life. Life (Basel) 2021; 11:498. [PMID: 34072344 PMCID: PMC8226951 DOI: 10.3390/life11060498] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 05/22/2021] [Accepted: 05/26/2021] [Indexed: 12/05/2022] Open
Abstract
In the search for life beyond Earth, distinguishing the living from the non-living is paramount. However, this distinction is often elusive, as the origin of life is likely a stepwise evolutionary process, not a singular event. Regardless of the favored origin of life model, an inherent "grayness" blurs the theorized threshold defining life. Here, we explore the ambiguities between the biotic and the abiotic at the origin of life. The role of grayness extends into later transitions as well. By recognizing the limitations posed by grayness, life detection researchers will be better able to develop methods sensitive to prebiotic chemical systems and life with alternative biochemistries.
Collapse
Affiliation(s)
- Hillary H. Smith
- Department of Geosciences, The Pennsylvania State University, University Park, PA 16802, USA;
- Earth and Environmental Systems Institute, The Pennsylvania State University, University Park, PA 16802, USA
| | - Andrew S. Hyde
- Department of Geosciences, The Pennsylvania State University, University Park, PA 16802, USA;
- Earth and Environmental Systems Institute, The Pennsylvania State University, University Park, PA 16802, USA
| | - Danielle N. Simkus
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA; (D.N.S.); (H.V.G.); (L.C.); (C.I.P.)
- NASA Postdoctoral Program, USRA, Columbia, MD 20146, USA
- Department of Physics, Catholic University of America, Washington, DC 20064, USA
| | - Eric Libby
- Santa Fe Institute, Santa Fe, NM 87501, USA; (E.L.); (C.P.K.); (N.M.G.)
- Department of Mathematics and Mathematical Statistics, Umeå University, 90187 Umeå, Sweden
- Icelab, Umeå University, 90187 Umeå, Sweden
| | - Sarah E. Maurer
- Department of Chemistry and Biochemistry, Central Connecticut State University, New Britain, CT 06050, USA;
| | - Heather V. Graham
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA; (D.N.S.); (H.V.G.); (L.C.); (C.I.P.)
- Department of Physics, Catholic University of America, Washington, DC 20064, USA
| | | | | | - Luoth Chou
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA; (D.N.S.); (H.V.G.); (L.C.); (C.I.P.)
- NASA Postdoctoral Program, USRA, Columbia, MD 20146, USA
- Department of Biology, Georgetown University, Washington, DC 20057, USA
| | - Andrew D. Ellington
- Department of Molecular Biosciences, College of Natural Sciences, The University of Texas at Austin, Austin, TX 78712, USA;
- Center for Systems and Synthetic Biology, The University of Texas at Austin, Austin, TX 78712, USA
| | - G. Matthew Fricke
- Department of Computer Science, University of New Mexico, Albuquerque, NM 87108, USA;
| | - Peter R. Girguis
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA;
| | - Natalie M. Grefenstette
- Santa Fe Institute, Santa Fe, NM 87501, USA; (E.L.); (C.P.K.); (N.M.G.)
- Blue Marble Space Institute of Science, Seattle, WA 98104, USA
| | - Chad I. Pozarycki
- NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA; (D.N.S.); (H.V.G.); (L.C.); (C.I.P.)
- Department of Biology, Georgetown University, Washington, DC 20057, USA
| | - Christopher H. House
- Department of Geosciences, The Pennsylvania State University, University Park, PA 16802, USA;
- Earth and Environmental Systems Institute, The Pennsylvania State University, University Park, PA 16802, USA
| | - Sarah Stewart Johnson
- Department of Biology, Georgetown University, Washington, DC 20057, USA
- Science, Technology and International Affairs Program, Georgetown University, Washington, DC 20057, USA
| |
Collapse
|
8
|
Toparlak Ö, Wang A, Mansy SS. Population-Level Membrane Diversity Triggers Growth and Division of Protocells. JACS AU 2021; 1:560-568. [PMID: 34467319 PMCID: PMC8395648 DOI: 10.1021/jacsau.0c00079] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Indexed: 06/01/2023]
Abstract
To date, multiple mechanisms have been described for the growth and division of model protocells, all of which exploit the lipid dynamics of fatty acids. In some examples, the more heterogeneous aggregate consisting of fatty acid and diacyl phospholipid or fatty acid and peptide grows at the expense of the more homogeneous aggregate containing a restricted set of lipids with similar dynamics. Imbalances between surface area and volume during growth can generate filamentous vesicles, which are typically divided by shear forces. Here, we describe another pathway for growth and division that depends simply on differences in the compositions of fatty acid membranes without additional components. Growth is driven by the thermodynamically favorable mixing of lipids between two populations, i.e., the system as a whole proceeds toward equilibrium. Division is the result of growth-induced curvature. Importantly, growth and division do not require a specific composition of lipids. For example, vesicles made from one type of lipid, e.g., short-chain fatty acids, grow and divide when fed with vesicles consisting of another type of lipid, e.g., long-chain fatty acids, and vice versa. After equilibration, additional rounds of growth and division could potentially proceed by the introduction of compositionally distinct aggregates. Since prebiotic synthesis likely gave rise to mixtures of lipids, the data are consistent with the presence of growing and dividing protocells on the prebiotic Earth.
Collapse
Affiliation(s)
- Ö.
Duhan Toparlak
- Department
of Cellular, Computational and Integrative Biology (D-CIBIO), University of Trento, Via Sommarive 9, 38123 Povo, TN, Italy
| | - Anna Wang
- School
of Chemistry and Australian Centre for Astrobiology, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Sheref S. Mansy
- Department
of Cellular, Computational and Integrative Biology (D-CIBIO), University of Trento, Via Sommarive 9, 38123 Povo, TN, Italy
- Department
of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, AB T6G
2G2, Canada
| |
Collapse
|
9
|
Misuraca L, Demé B, Oger P, Peters J. Alkanes increase the stability of early life membrane models under extreme pressure and temperature conditions. Commun Chem 2021; 4:24. [PMID: 36697785 PMCID: PMC9814696 DOI: 10.1038/s42004-021-00467-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 01/14/2021] [Indexed: 01/31/2023] Open
Abstract
Terrestrial life appeared on our planet within a time window of [4.4-3.5] billion years ago. During that time, it is suggested that the first proto-cellular forms developed in the surrounding of deep-sea hydrothermal vents, oceanic crust fractures that are still present nowadays. However, these environments are characterized by extreme temperature and pressure conditions that question the early membrane compartment's capability to endure a stable structural state. Recent studies proposed an adaptive strategy employed by present-day extremophiles: the use of apolar molecules as structural membrane components in order to tune the bilayer dynamic response when needed. Here we extend this hypothesis on early life protomembrane models, using linear and branched alkanes as apolar stabilizing molecules of prebiotic relevance. The structural ordering and chain dynamics of these systems have been investigated as a function of temperature and pressure. We found that both types of alkanes studied, even the simplest linear ones, impact highly the multilamellar vesicle ordering and chain dynamics. Our data show that alkane-enriched membranes have a lower multilamellar vesicle swelling induced by the temperature increase and are significantly less affected by pressure variation as compared to alkane-free samples, suggesting a possible survival strategy for the first living forms.
Collapse
Affiliation(s)
- Loreto Misuraca
- grid.4444.00000 0001 2112 9282Univ. Grenoble Alpes, CNRS, LIPhy, Grenoble, France ,grid.156520.50000 0004 0647 2236Institut Laue - Langevin, Grenoble, France
| | - Bruno Demé
- grid.156520.50000 0004 0647 2236Institut Laue - Langevin, Grenoble, France
| | - Philippe Oger
- grid.7849.20000 0001 2150 7757Univ Lyon, INSA Lyon, CNRS UMR5240, Villeurbanne, France
| | - Judith Peters
- grid.4444.00000 0001 2112 9282Univ. Grenoble Alpes, CNRS, LIPhy, Grenoble, France ,grid.156520.50000 0004 0647 2236Institut Laue - Langevin, Grenoble, France
| |
Collapse
|
10
|
Askenase PW. Ancient Evolutionary Origin and Properties of Universally Produced Natural Exosomes Contribute to Their Therapeutic Superiority Compared to Artificial Nanoparticles. Int J Mol Sci 2021; 22:1429. [PMID: 33572657 PMCID: PMC7866973 DOI: 10.3390/ijms22031429] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2020] [Revised: 01/20/2021] [Accepted: 01/22/2021] [Indexed: 12/14/2022] Open
Abstract
Extracellular vesicles (EVs), such as exosomes, are newly recognized fundamental, universally produced natural nanoparticles of life that are seemingly involved in all biologic processes and clinical diseases. Due to their universal involvements, understanding the nature and also the potential therapeutic uses of these nanovesicles requires innovative experimental approaches in virtually every field. Of the EV group, exosome nanovesicles and larger companion micro vesicles can mediate completely new biologic and clinical processes dependent on the intercellular transfer of proteins and most importantly selected RNAs, particularly miRNAs between donor and targeted cells to elicit epigenetic alterations inducing functional cellular changes. These recipient acceptor cells are nearby (paracrine transfers) or far away after distribution via the circulation (endocrine transfers). The major properties of such vesicles seem to have been conserved over eons, suggesting that they may have ancient evolutionary origins arising perhaps even before cells in the primordial soup from which life evolved. Their potential ancient evolutionary attributes may be responsible for the ability of some modern-day exosomes to withstand unusually harsh conditions, perhaps due to unique membrane lipid compositions. This is exemplified by ability of the maternal milk exosomes to survive passing the neonatal acid/enzyme rich stomach. It is postulated that this resistance also applies to their durable presence in phagolysosomes, thus suggesting a unique intracellular release of their contained miRNAs. A major discussed issue is the generally poorly realized superiority of these naturally evolved nanovesicles for therapies when compared to human-engineered artificial nanoparticles, e.g., for the treatment of diseases like cancers.
Collapse
Affiliation(s)
- Phillip W Askenase
- Department of Internal Medicine, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
| |
Collapse
|
11
|
Lopez A, Fayolle D, Fiore M, Strazewski P. Chemical Analysis of Lipid Boundaries after Consecutive Growth and Division of Supported Giant Vesicles. iScience 2020; 23:101677. [PMID: 33163935 PMCID: PMC7609504 DOI: 10.1016/j.isci.2020.101677] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 09/21/2020] [Accepted: 10/09/2020] [Indexed: 11/17/2022] Open
Abstract
The reproduction of the shape of giant vesicles usually results in the increase of their "population" size. This may be achieved on giant vesicles by appropriately supplying "mother" vesicles with membranogenic amphiphiles. The next "generation" of "daughter" vesicles obtained from this "feeding" is inherently difficult to distinguish from the original mothers. Here we report on a method for the consecutive feeding with different fatty acids that each provoke membrane growth and detachment of daughter vesicles from glass microsphere-supported phospholipidic mother vesicles. We discovered that a saturated fatty acid was carried over to the next generation of mothers better than two unsaturated congeners. This has an important bearing on the growth and replication of primitive compartments at the early stages of life. Microsphere-supported vesicles are also a precise analytical tool.
Collapse
Affiliation(s)
- Augustin Lopez
- Université de Lyon, Université Claude Bernard Lyon 1, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Bâtiment Edgar Lederer, 1 Rue Victor Grignard, 69622 Villeurbanne Cedex, France
| | - Dimitri Fayolle
- Université de Lyon, Université Claude Bernard Lyon 1, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Bâtiment Edgar Lederer, 1 Rue Victor Grignard, 69622 Villeurbanne Cedex, France
| | - Michele Fiore
- Université de Lyon, Université Claude Bernard Lyon 1, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Bâtiment Edgar Lederer, 1 Rue Victor Grignard, 69622 Villeurbanne Cedex, France
| | - Peter Strazewski
- Université de Lyon, Université Claude Bernard Lyon 1, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Bâtiment Edgar Lederer, 1 Rue Victor Grignard, 69622 Villeurbanne Cedex, France
| |
Collapse
|
12
|
Sarkar S, Das S, Dagar S, Joshi MP, Mungi CV, Sawant AA, Patki GM, Rajamani S. Prebiological Membranes and Their Role in the Emergence of Early Cellular Life. J Membr Biol 2020; 253:589-608. [PMID: 33200235 DOI: 10.1007/s00232-020-00155-w] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 11/08/2020] [Indexed: 01/30/2023]
Abstract
Membrane compartmentalization is a fundamental feature of contemporary cellular life. Given this, it is rational to assume that at some stage in the early origins of life, membrane compartments would have potentially emerged to form a dynamic semipermeable barrier in primitive cells (protocells), protecting them from their surrounding environment. It is thought that such prebiological membranes would likely have played a crucial role in the emergence and evolution of life on the early Earth. Extant biological membranes are highly organized and complex, which is a consequence of a protracted evolutionary history. On the other hand, prebiotic membrane assemblies, which are thought to have preceded sophisticated contemporary membranes, are hypothesized to have been relatively simple and composed of single chain amphiphiles. Recent studies indicate that the evolution of prebiotic membranes potentially resulted from interactions between the membrane and its physicochemical environment. These studies have also speculated on the origin, composition, function and influence of environmental conditions on protocellular membranes as the niche parameters would have directly influenced their composition and biophysical properties. Nonetheless, the evolutionary pathways involved in the transition from prebiological membranes to contemporary membranes are largely unknown. This review critically evaluates existing research on prebiotic membranes in terms of their probable origin, composition, energetics, function and evolution. Notably, we outline new approaches that can further our understanding about how prebiotic membranes might have evolved in response to relevant physicochemical parameters that would have acted as pertinent selection pressures on the early Earth.
Collapse
Affiliation(s)
- Susovan Sarkar
- Department of Biology, Indian Institute of Science Education and Research, Pune, 411008, India
| | - Souradeep Das
- Department of Biology, Indian Institute of Science Education and Research, Pune, 411008, India
| | - Shikha Dagar
- Department of Biology, Indian Institute of Science Education and Research, Pune, 411008, India
| | - Manesh Prakash Joshi
- Department of Biology, Indian Institute of Science Education and Research, Pune, 411008, India
| | - Chaitanya V Mungi
- Department of Biology, Indian Institute of Science Education and Research, Pune, 411008, India
| | - Anupam A Sawant
- Department of Biology, Indian Institute of Science Education and Research, Pune, 411008, India
| | - Gauri M Patki
- Department of Biology, Indian Institute of Science Education and Research, Pune, 411008, India
| | - Sudha Rajamani
- Department of Biology, Indian Institute of Science Education and Research, Pune, 411008, India.
| |
Collapse
|
13
|
Misuraca L, Caliò A, Grillo I, Grélard A, Oger PM, Peters J, Demé B. High-Temperature Behavior of Early Life Membrane Models. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:13516-13526. [PMID: 33146533 DOI: 10.1021/acs.langmuir.0c02258] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Origin of life scenarios generally assume an onset of cell formation in terrestrial hot springs or in the deep oceans close to hot vents, where energy was available for non-enzymatic reactions. Membranes of the protocells had therefore to withstand extreme conditions different from what is found on the Earth surface today. We present here an exhaustive study of temperature stability up to 80 °C of vesicles formed by a mixture of short-chain fatty acids and alcohols, which are plausible candidates for membranes permitting the compartmentalization of protocells. We confirm that the presence of alcohol has a strong structuring and stabilizing impact on the lamellar structures. Moreover and most importantly, at a high temperature (> 60 °C), we observe a conformational transition in the vesicles, which results from vesicular fusion. Because all the most likely environments for the origin of life involve high temperatures, our results imply the need to take into account such a transition and its effect when studying the behavior of a protomembrane model.
Collapse
Affiliation(s)
- Loreto Misuraca
- Univ. Grenoble Alpes, CNRS, LIPhy, 38000 Grenoble, France
- Institut Laue - Langevin, 38042 Grenoble, France
| | - Antonino Caliò
- Institut Laue - Langevin, 38042 Grenoble, France
- INSA Lyon, Université de Lyon, CNRS, UMR5240 Villeurbanne, France
| | | | | | | | - Judith Peters
- Univ. Grenoble Alpes, CNRS, LIPhy, 38000 Grenoble, France
- Institut Laue - Langevin, 38042 Grenoble, France
| | - Bruno Demé
- Institut Laue - Langevin, 38042 Grenoble, France
| |
Collapse
|
14
|
Liu Z, Zhou W, Qi C, Kong T. Interface Engineering in Multiphase Systems toward Synthetic Cells and Organelles: From Soft Matter Fundamentals to Biomedical Applications. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2002932. [PMID: 32954548 DOI: 10.1002/adma.202002932] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/19/2020] [Indexed: 06/11/2023]
Abstract
Synthetic cells have a major role in gaining insight into the complex biological processes of living cells; they also give rise to a range of emerging applications from gene delivery to enzymatic nanoreactors. Living cells rely on compartmentalization to orchestrate reaction networks for specialized and coordinated functions. Principally, the compartmentalization has been an essential engineering theme in constructing cell-mimicking systems. Here, efforts to engineer liquid-liquid interfaces of multiphase systems into membrane-bounded and membraneless compartments, which include lipid vesicles, polymer vesicles, colloidosomes, hybrids, and coacervate droplets, are summarized. Examples are provided of how these compartments are designed to imitate biological behaviors or machinery, including molecule trafficking, growth, fusion, energy conversion, intercellular communication, and adaptivity. Subsequently, the state-of-art applications of these cell-inspired synthetic compartments are discussed. Apart from being simplified and cell models for bridging the gap between nonliving matter and cellular life, synthetic compartments also are utilized as intracellular delivery vehicles for nuclei acids and nanoreactors for biochemical synthesis. Finally, key challenges and future directions for achieving the full potential of synthetic cells are highlighted.
Collapse
Affiliation(s)
- Zhou Liu
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, 518000, China
| | - Wen Zhou
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, 518000, China
| | - Cheng Qi
- College of Mechatronics and Control Engineering, Shenzhen University, Shenzhen, 518000, China
| | - Tiantian Kong
- Department of Biomedical Engineering, School of Medicine, Shenzhen University, Shenzhen, Guangdong, 518000, China
| |
Collapse
|
15
|
Dalai P, Sahai N. A Model Protometabolic Pathway Across Protocell Membranes Assisted by Photocatalytic Minerals. J Phys Chem B 2019. [PMID: 31869230 DOI: 10.1021/acs.jpcb.9b10127] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Protocell analogs (lipid vesicles) to modern cell membranes have been postulated as compartments that may have been involved in primordial metabolism during the transition from geochemistry to biochemistry on early Earth. The transduction of light energy into chemical energy for metabolism was a key step in the transition from the earliest metabolisms to phototrophy. Photocatalytic minerals may have served the role of enzymes during these transitional stages. Here, we demonstrate a simple photoheterotrophic protometabolism promoted by photocatalytic minerals across a model protocell (vesicle) membrane. These minerals in the extra-vesicular medium utilized light energy to drive a coupled, multi-step transmembrane electron transfer reaction (TMETR), while simultaneously generating a transmembrane pH gradient and reducing nicotinamide adenine dinucleotide (NAD+) to NADH within the vesicle. The proton gradient or chemiosmotic potential could have provided a basis for adenosine triphosphate (ATP) synthesis and NADH could potentially have driven further metabolic chemistry inside the protocells.
Collapse
|
16
|
Promotion of protocell self-assembly from mixed amphiphiles at the origin of life. Nat Ecol Evol 2019; 3:1705-1714. [PMID: 31686020 DOI: 10.1038/s41559-019-1015-y] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 09/25/2019] [Indexed: 01/01/2023]
Abstract
Vesicles formed from single-chain amphiphiles (SCAs) such as fatty acids probably played an important role in the origin of life. A major criticism of the hypothesis that life arose in an early ocean hydrothermal environment is that hot temperatures, large pH gradients, high salinity and abundant divalent cations should preclude vesicle formation. However, these arguments are based on model vesicles using 1-3 SCAs, even though Fischer-Tropsch-type synthesis under hydrothermal conditions produces a wide array of fatty acids and 1-alkanols, including abundant C10-C15 compounds. Here, we show that mixtures of these C10-C15 SCAs form vesicles in aqueous solutions between pH ~6.5 and >12 at modern seawater concentrations of NaCl, Mg2+ and Ca2+. Adding C10 isoprenoids improves vesicle stability even further. Vesicles form most readily at temperatures of ~70 °C and require salinity and strongly alkaline conditions to self-assemble. Thus, alkaline hydrothermal conditions not only permit protocell formation at the origin of life but actively favour it.
Collapse
|
17
|
Dalai P, Sahai N. Mineral–Lipid Interactions in the Origins of Life. Trends Biochem Sci 2019; 44:331-341. [DOI: 10.1016/j.tibs.2018.11.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 11/20/2018] [Accepted: 11/27/2018] [Indexed: 10/27/2022]
|
18
|
Abstract
IMPACT STATEMENT Advances in the understanding of the biophysics of membranes, the nonenzymatic and enzymatic polymerization of RNA, and in the design of complex chemical reaction networks have led to a new, integrated way of viewing the shared chemistry needed to sustain life. Although a protocell capable of Darwinian evolution has yet to be built, the seemingly disparate pieces are beginning to fit together. At the very least, better cellular mimics are on the horizon that will likely teach us much about the physicochemical underpinnings of cellular life.
Collapse
|
19
|
Jia MQ, Liu QZ, Zhu LJ, Zhang Y, Chen ZX. Influence of polysaccharides on the dynamic self-assembly of medium-chain fatty acid vesicles and hydrolysis of decanoic acid anhydrides. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2018.07.055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
20
|
Unveiling the pH dependent interaction between bolaamphiphiles (dicarboxylic acids) and C10TAB (decyltrimethylammonium bromide) in aqueous medium. J Colloid Interface Sci 2018; 518:225-233. [DOI: 10.1016/j.jcis.2018.02.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 02/03/2018] [Accepted: 02/05/2018] [Indexed: 01/31/2023]
|
21
|
Jin L, Kamat N, Jena S, Szostak J. Fatty Acid/Phospholipid Blended Membranes: A Potential Intermediate State in Protocellular Evolution. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1704077. [PMID: 29479815 PMCID: PMC6278924 DOI: 10.1002/smll.201704077] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 01/12/2018] [Indexed: 05/29/2023]
Abstract
Prior to the evolution of membrane proteins, intrinsic membrane stability and permeability to polar solutes are essential features of a primitive cell membrane. These features are difficult to achieve simultaneously in model protocells made of either pure fatty acid or phospholipid membranes, raising the intriguing question of how the transition from fatty acid to phospholipid membranes might have occurred while continuously supporting encapsulated reactions required for genomic replication. Here, the properties of a blended membrane system composed of both oleic acid (OA), a monoacyl fatty acid, and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), a diacyl phospholipid are described. This hybrid vesicle system exhibits high stability to divalent cations (Mg2+ ), while simultaneously maintaining its permeability to small charged molecules such as nucleotides and divalent ions such as Mg2+ . This combination of features facilitates key reactions expected to occur during a transition from primitive to modern cells, including nonenzymatic RNA replication, and is also compatible with highly evolved functions such as the ribosomal translation of a protein. The observations support the hypothesis that the early transition from fatty acid to phospholipid membranes could be accomplished through intermediate states in which membranes are composed of amphiphile mixtures, and do not require protein transporters.
Collapse
Affiliation(s)
- L. Jin
- Howard Hughes Medical Institute, Department of Molecular Biology
and Center for Computational and Integrative Biology, Massachusetts General
Hospital, Boston, MA 02114, USA
- Department of Biomedical Engineering, Boston University, Boston, MA
02215, USA
| | - N.P. Kamat
- Howard Hughes Medical Institute, Department of Molecular Biology
and Center for Computational and Integrative Biology, Massachusetts General
Hospital, Boston, MA 02114, USA
- Department of Biomedical Engineering, Northwestern University,
Evanston, IL 60208, USA
| | - S. Jena
- Department of Physics, Harvard University, Cambridge, MA 02138,
USA
| | - J.W. Szostak
- Howard Hughes Medical Institute, Department of Molecular Biology
and Center for Computational and Integrative Biology, Massachusetts General
Hospital, Boston, MA 02114, USA,
| |
Collapse
|
22
|
Fayolle D, Altamura E, D'Onofrio A, Madanamothoo W, Fenet B, Mavelli F, Buchet R, Stano P, Fiore M, Strazewski P. Crude phosphorylation mixtures containing racemic lipid amphiphiles self-assemble to give stable primitive compartments. Sci Rep 2017; 7:18106. [PMID: 29273739 PMCID: PMC5741756 DOI: 10.1038/s41598-017-18053-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 11/29/2017] [Indexed: 01/13/2023] Open
Abstract
It is an open question how the chemical structure of prebiotic vesicle-forming amphiphiles complexified to produce robust primitive compartments that could safely host foreign molecules. Previous work suggests that comparingly labile vesicles composed of plausibly prebiotic fatty acids were eventually chemically transformed with glycerol and a suitable phosphate source into phospholipids that would form robust vesicles. Here we show that phosphatidic acid (PA) and phosphatidylethanolamine (PE) lipids can be obtained from racemic dioleoyl glycerol under plausibly prebiotic phosphorylation conditions. Upon in situ hydration of the crude phosphorylation mixtures only those that contained rac-DOPA (not rac-DOPE) generated stable giant vesicles that were capable of encapsulating water-soluble probes, as evidenced by confocal microscopy and flow cytometry. Chemical reaction side-products (identified by IR and MS and quantified by 1H NMR) acted as co-surfactants and facilitated vesicle formation. To mimic the compositional variation of such primitive lipid mixtures, self-assembly of a combinatorial set of the above amphiphiles was tested, revealing that too high dioleoyl glycerol contents inhibited vesicle formation. We conclude that a decisive driving force for the gradual transition from unstable fatty acid vesicles to robust diacylglyceryl phosphate vesicles was to avoid the accumulation of unphosphorylated diacylglycerols in primitive vesicle membranes.
Collapse
Affiliation(s)
- Dimitri Fayolle
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Université de Lyon, Claude Bernard Lyon 1, 43 bvd du 11 Novembre 1918, F-69622, Villeurbanne Cedex, France
| | - Emiliano Altamura
- Department of Chemistry, University of Bari, Via E. Orabona 4, I-70125, Bari, Italy
| | - Alice D'Onofrio
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Université de Lyon, Claude Bernard Lyon 1, 43 bvd du 11 Novembre 1918, F-69622, Villeurbanne Cedex, France
| | - Warren Madanamothoo
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Université de Lyon, Claude Bernard Lyon 1, 43 bvd du 11 Novembre 1918, F-69622, Villeurbanne Cedex, France
| | - Bernard Fenet
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Université de Lyon, Claude Bernard Lyon 1, 43 bvd du 11 Novembre 1918, F-69622, Villeurbanne Cedex, France
| | - Fabio Mavelli
- Department of Chemistry, University of Bari, Via E. Orabona 4, I-70125, Bari, Italy
| | - René Buchet
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Université de Lyon, Claude Bernard Lyon 1, 43 bvd du 11 Novembre 1918, F-69622, Villeurbanne Cedex, France
| | - Pasquale Stano
- Biological and Environmental Science and Technology Department, University of Salento, Ecotekne, I-73100, Lecce, Italy.
| | - Michele Fiore
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Université de Lyon, Claude Bernard Lyon 1, 43 bvd du 11 Novembre 1918, F-69622, Villeurbanne Cedex, France.
| | - Peter Strazewski
- Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, Université de Lyon, Claude Bernard Lyon 1, 43 bvd du 11 Novembre 1918, F-69622, Villeurbanne Cedex, France.
| |
Collapse
|
23
|
Chemical Transformations in Proto-Cytoplasmic Media. Phosphorus Coupling in the Silica Hydrogel Phase. Life (Basel) 2017; 7:life7040045. [PMID: 29156594 PMCID: PMC5745558 DOI: 10.3390/life7040045] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 10/12/2017] [Accepted: 10/27/2017] [Indexed: 01/03/2023] Open
Abstract
It has been proposed that prebiotic chemical studies on the emergence of primitive life would be most relevant when performed in a hydrogel, rather than an aqueous, environment. In this paper we describe the ambient temperature coupling of phosphorus oxyacids [Pi] mediated by Fe(II) under aerobic conditions within a silica hydrogel (SHG) environment. We have chosen to examine SHGs as they have considerable geological precedence as key phases in silicification en route to rock formation. Following a description of the preparation and characterization studies on our SHG formulations, coupling experiments between Pi species are described across multiple permutations of (i) Pi compound; (ii) gel formulation; (iii) metal salt additive; and (iv) pH-modifying agent. The results suggest that successful Pi coupling, indicated by observation of pyrophosphate [PPi(V)] via 31P-NMR spectroscopy, takes place when the following components are present: (i) a mixture of mixture of Pi(III) and Pi(V) or pure PPi(III– V); (ii) Fe(II); (iii) acetic or formic acid (not hydrochloric acid); (iv) aerobic conditions or the presence of H2O2 as an oxidant; and (v) the presence of a gel system. On the basis of these, and aqueous control reactions, we suggest mechanistic possibilities.
Collapse
|
24
|
Maurer S. The Impact of Salts on Single Chain Amphiphile Membranes and Implications for the Location of the Origin of Life. Life (Basel) 2017; 7:life7040044. [PMID: 29135960 PMCID: PMC5745557 DOI: 10.3390/life7040044] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 11/06/2017] [Accepted: 11/07/2017] [Indexed: 12/01/2022] Open
Abstract
One of the key steps in the origins of life was the formation of a membrane to separate protocells from their environment. These membranes are proposed to have been formed out of single chain amphiphiles, which are less stable than the dialkyl lipids used to form modern membranes. This lack of stability, specifically for decanoate, is often used to refute ocean locations for the origins of life. This review addresses the formation of membranes in hydrothermal-vent like conditions, as well as other environmental constraints. Specifically, single chain amphiphiles can form membranes at high sea salt concentrations (150 g/L), high temperatures (65 °C), and a wide pH range (2 to 10). It additionally discusses the major challenges and advantages of membrane formation in both ocean and fresh water locations.
Collapse
Affiliation(s)
- Sarah Maurer
- Department of Chemistry and Biochemistry, Central Connecticut State University, 1615 Stanley St., New Britain, CT 06050, USA.
| |
Collapse
|
25
|
Hanczyc MM, Monnard PA. Primordial membranes: more than simple container boundaries. Curr Opin Chem Biol 2017; 40:78-86. [DOI: 10.1016/j.cbpa.2017.07.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Revised: 06/19/2017] [Accepted: 07/20/2017] [Indexed: 01/14/2023]
|
26
|
Singh S, Bhadoria A, Parikh K, Yadav SK, Kumar S, Aswal VK, Kumar S. Self-Assembly in Aqueous Oppositely Charged Gemini Surfactants: A Correlation between Morphology and Solubilization Efficacy. J Phys Chem B 2017; 121:8756-8766. [DOI: 10.1021/acs.jpcb.7b03989] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sneha Singh
- Applied Chemistry
Department, Faculty of Technology and Engineering, The Maharaja Sayajirao University of Baroda, Vadodara 390 001, India
| | - Arti Bhadoria
- Applied Chemistry
Department, Faculty of Technology and Engineering, The Maharaja Sayajirao University of Baroda, Vadodara 390 001, India
| | - Kushan Parikh
- Department of Applied Science, Faculty of Life, Health & Applied Science, ITM Vocational University, Vadodara 391 760, India
| | - Sanjay Kumar Yadav
- Soft
Material Research Laboratory, Department of Chemistry, Faculty of
Science, The Maharaja Sayajirao University of Baroda, Vadodara 390 002, India
| | - Sugam Kumar
- Solid State Physics
Divison, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
| | - V. K. Aswal
- Solid State Physics
Divison, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
| | - Sanjeev Kumar
- Applied Chemistry
Department, Faculty of Technology and Engineering, The Maharaja Sayajirao University of Baroda, Vadodara 390 001, India
| |
Collapse
|
27
|
Kee TP, Monnard PA. Chemical systems, chemical contiguity and the emergence of life. Beilstein J Org Chem 2017; 13:1551-1563. [PMID: 28904604 PMCID: PMC5564265 DOI: 10.3762/bjoc.13.155] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 07/11/2017] [Indexed: 12/17/2022] Open
Abstract
Charting the emergence of living cells from inanimate matter remains an intensely challenging scientific problem. The complexity of the biochemical machinery of cells with its exquisite intricacies hints at cells being the product of a long evolutionary process. Research on the emergence of life has long been focusing on specific, well-defined problems related to one aspect of cellular make-up, such as the formation of membranes or the build-up of information/catalytic apparatus. This approach is being gradually replaced by a more "systemic" approach that privileges processes inherent to complex chemical systems over specific isolated functional apparatuses. We will summarize the recent advances in system chemistry and show that chemical systems in the geochemical context imply a form of chemical contiguity in the syntheses of the various molecules that precede modern biomolecules.
Collapse
Affiliation(s)
- Terrence P Kee
- School of Chemistry, University of Leeds, Leeds LS2 9JT, UK
| | - Pierre-Alain Monnard
- Institute of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| |
Collapse
|
28
|
Strong SE, Eaves JD. Linear Response Theory for Water Transport Through Dry Nanopores. J Phys Chem A 2017; 121:5377-5382. [PMID: 28598162 DOI: 10.1021/acs.jpca.7b03192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Porous two-dimensional crystals like graphene have the potential to revolutionize reverse-osmosis membrane technology. The permeability is a common figure of merit that describes the ease with which water flows through a membrane. For two-dimensional crystals, the permeability can be orders of magnitude higher than it is in conventional reverse-osmosis membranes. We apply our Gaussian Dynamics nonequilibrium molecular dynamics simulation method to very hydrophobic two-dimensional membranes and find that the current-pressure drop relationship becomes nonlinear. In this regime, the conventional permeability is an inadequate descriptor of the passage process, and the transport mechanism becomes a two-step one. The backing pressure first causes the pore to wet, and after it reaches a threshold pressure, water transport takes place from the wet state. We recover a simple description of the transport process by applying linear response theory with respect to the wet reference state rather than the dry one. A macroscopic thermodynamic argument supports our mechanistic description and predicts the wetting threshold pressure as a function of the contact angle.
Collapse
Affiliation(s)
- Steven E Strong
- Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309, United States
| | - Joel D Eaves
- Department of Chemistry and Biochemistry, University of Colorado , Boulder, Colorado 80309, United States
| |
Collapse
|
29
|
Wamberg MC, Pedersen PL, Löffler PMG, Albertsen AN, Maurer SE, Nielsen KA, Monnard PA. Synthesis of Lipophilic Guanine N-9 Derivatives: Membrane Anchoring of Nucleobases Tailored to Fatty Acid Vesicles. Bioconjug Chem 2017; 28:1893-1905. [PMID: 28587449 DOI: 10.1021/acs.bioconjchem.7b00228] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Covalent or noncovalent surface functionalization of soft-matter structures is an important tool for tailoring their function and stability. Functionalized surfaces and nanoparticles have found numerous applications in drug delivery and diagnostics, and new functionalization chemistry is continuously being developed in the discipline of bottom-up systems chemistry. The association of polar functional molecules, e.g., molecular recognition agents, with soft-matter structures can be achieved by derivatization with alkyl chains, allowing noncovalent anchoring into amphiphilic membranes. We report the synthesis of five new guanine-N9 derivatives bearing alkyl chains with different attachment chemistries, exploiting a synthesis pathway that allows a flexible choice of hydrophobic anchor moiety. In this study, these guanine derivatives were functionalized with C10 chains for insertion into decanoic acid bilayer structures, in which both alkyl chain length and attachment chemistry determined their interaction with the membrane. Incubation of these guanine conjugates, as solids, with a decanoic acid vesicle suspension, showed that ether- and triazole-linked C10 anchors yielded an increased partitioning of the guanine derivative into the membranous phase compared to directly N-9-linked saturated alkyl anchors. Decanoic acid vesicle membranes could be loaded with up to 5.5 mol % guanine derivative, a 6-fold increase over previous limits. Thus, anchor chemistries exhibiting favorable interactions with a bilayer's hydrophilic surface can significantly increase the degree of structure functionalization.
Collapse
Affiliation(s)
- Michael C Wamberg
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , Campusvej 55, DK-5230 Odense, Denmark
| | - Pernille L Pedersen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , Campusvej 55, DK-5230 Odense, Denmark
| | - Philipp M G Löffler
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , Campusvej 55, DK-5230 Odense, Denmark
| | - Anders N Albertsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , Campusvej 55, DK-5230 Odense, Denmark
| | - Sarah E Maurer
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , Campusvej 55, DK-5230 Odense, Denmark
| | - Kent A Nielsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , Campusvej 55, DK-5230 Odense, Denmark
| | - Pierre-Alain Monnard
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , Campusvej 55, DK-5230 Odense, Denmark
| |
Collapse
|
30
|
Permeability-driven selection in a semi-empirical protocell model: the roots of prebiotic systems evolution. Sci Rep 2017; 7:3141. [PMID: 28600550 PMCID: PMC5466667 DOI: 10.1038/s41598-017-02799-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 04/19/2017] [Indexed: 01/30/2023] Open
Abstract
The origin-of-life problem has been traditionally conceived as the chemical challenge to find the type of molecule and free-solution reaction dynamics that could have started Darwinian evolution. Different autocatalytic and ‘self-replicative’ molecular species have been extensively investigated, together with plausible synthetic pathways that might have led, abiotically, to such a minimalist scenario. However, in addition to molecular kinetics or molecular evolutionary dynamics, other physical and chemical constraints (like compartmentalization, differential diffusion, selective transport, osmotic forces, energetic couplings) could have been crucial for the cohesion, functional integration, and intrinsic stability/robustness of intermediate systems between chemistry and biology. These less acknowledged mechanisms of interaction and molecular control might have made the initial pathways to prebiotic systems evolution more intricate, but were surely essential for sustaining far-from-equilibrium chemical dynamics, given their functional relevance in all modern cells. Here we explore a protocellular scenario in which some of those additional constraints/mechanisms are addressed, demonstrating their ‘system-level’ implications. In particular, an experimental study on the permeability of prebiotic vesicle membranes composed of binary lipid mixtures allows us to construct a semi-empirical model where protocells are able to reproduce and undergo an evolutionary process based on their coupling with an internal chemistry that supports lipid synthesis.
Collapse
|
31
|
Rasmussen S, Constantinescu A, Svaneborg C. Generating minimal living systems from non-living materials and increasing their evolutionary abilities. Philos Trans R Soc Lond B Biol Sci 2016; 371:20150440. [PMID: 27431518 PMCID: PMC4958934 DOI: 10.1098/rstb.2015.0440] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/24/2016] [Indexed: 11/12/2022] Open
Abstract
We review lessons learned about evolutionary transitions from a bottom-up construction of minimal life. We use a particular systemic protocell design process as a starting point for exploring two fundamental questions: (i) how may minimal living systems emerge from non-living materials? and (ii) how may minimal living systems support increasingly more evolutionary richness? Under (i), we present what has been accomplished so far and discuss the remaining open challenges and their possible solutions. Under (ii), we present a design principle we have used successfully both for our computational and experimental protocellular investigations, and we conjecture how this design principle can be extended for enhancing the evolutionary potential for a wide range of systems.This article is part of the themed issue 'The major synthetic evolutionary transitions'.
Collapse
Affiliation(s)
- Steen Rasmussen
- Center for Fundamental Living Technology (FLinT), Department for Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA
| | - Adi Constantinescu
- Center for Fundamental Living Technology (FLinT), Department for Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark
| | - Carsten Svaneborg
- Center for Fundamental Living Technology (FLinT), Department for Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230 Odense, Denmark
| |
Collapse
|
32
|
Scheidler C, Sobotta J, Eisenreich W, Wächtershäuser G, Huber C. Unsaturated C3,5,7,9-Monocarboxylic Acids by Aqueous, One-Pot Carbon Fixation: Possible Relevance for the Origin of Life. Sci Rep 2016; 6:27595. [PMID: 27283227 PMCID: PMC4901337 DOI: 10.1038/srep27595] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 05/20/2016] [Indexed: 11/09/2022] Open
Abstract
All scientific approaches to the origin of life share a common problem: a chemical path to lipids as main constituents of extant cellular enclosures. Here we show by isotope-controlled experiments that unsaturated C3,5,7,9-monocarboxylic acids form by one-pot reaction of acetylene (C2H2) and carbon monoxide (CO) in contact with nickel sulfide (NiS) in hot aqueous medium. The primary products are toto-olefinic monocarboxylic acids with CO-derived COOH groups undergoing subsequent stepwise hydrogenation with CO as reductant. In the resulting unsaturated monocarboxylic acids the double bonds are mainly centrally located with mainly trans-configuration. The reaction conditions are compatible with an origin of life in volcanic-hydrothermal sub-seafloor flow ducts.
Collapse
Affiliation(s)
- Christopher Scheidler
- Lehrstuhl für Biochemie, Technische Universität München, Lichtenbergstraße 4, D-85747 Garching Germany
| | - Jessica Sobotta
- Lehrstuhl für Biochemie, Technische Universität München, Lichtenbergstraße 4, D-85747 Garching Germany
| | - Wolfgang Eisenreich
- Lehrstuhl für Biochemie, Technische Universität München, Lichtenbergstraße 4, D-85747 Garching Germany
| | | | - Claudia Huber
- Lehrstuhl für Biochemie, Technische Universität München, Lichtenbergstraße 4, D-85747 Garching Germany
| |
Collapse
|
33
|
Maurer SE, Nguyen G. Prebiotic Vesicle Formation and the Necessity of Salts. ORIGINS LIFE EVOL B 2016; 46:215-22. [PMID: 26590931 DOI: 10.1007/s11084-015-9476-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 11/05/2015] [Indexed: 10/22/2022]
Abstract
Self-assembly is considered one of the driving forces behind abiogenesis and would have been affected by the environmental conditions of early Earth. The formation of membranes is a key step in this process, and unlike large dialkyl membranes of modern cells the first membranes were likely formed from small single-chain amphiphiles, which are environment-sensitive. Fatty acids and their derivatives have been previously characterized in this role without concern for the concentrations of ionic solutes in the suspension. We determined the critical vesicle concentration (CVC) for three single-chain amphiphiles with increasing concentrations of NaCl. All amphiphile species had decreasing CVCs correlated to increasing NaCl concentrations. Decanoic acid and oleic acid were impacted more strongly than monoacylglycerol, likely because of electric shielding of the negatively charged headgroups in the presence of salt. There was no impact on the salt species as 100 mM NaBr, NaCl, and KCl all exhibited the same effect on CVC. This research shows the importance of salt in both the formation of life and in experimental design for aggregation experiments.
Collapse
Affiliation(s)
- Sarah E Maurer
- Department of Chemistry and Biochemistry, Central Connecticut State University, 1615 Stanley St., New Britain, CT, 06050, USA.
| | - Gunarso Nguyen
- Department of Chemistry and Biochemistry, Central Connecticut State University, 1615 Stanley St., New Britain, CT, 06050, USA
| |
Collapse
|
34
|
Adamala KP, Engelhart AE, Szostak JW. Collaboration between primitive cell membranes and soluble catalysts. Nat Commun 2016; 7:11041. [PMID: 26996603 PMCID: PMC4802160 DOI: 10.1038/ncomms11041] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 02/15/2016] [Indexed: 12/23/2022] Open
Abstract
One widely held model of early life suggests primitive cells consisted of simple RNA-based catalysts within lipid compartments. One possible selective advantage conferred by an encapsulated catalyst is stabilization of the compartment, resulting from catalyst-promoted synthesis of key membrane components. Here we show model protocell vesicles containing an encapsulated enzyme that promotes the synthesis of simple fatty acid derivatives become stabilized to Mg2+, which is required for ribozyme activity and RNA synthesis. Thus, protocells capable of such catalytic transformations would have enjoyed a selective advantage over other protocells in high Mg2+ environments. The synthetic transformation requires both the catalyst and vesicles that solubilize the water-insoluble precursor lipid. We suggest that similar modified lipids could have played a key role in early life, and that primitive lipid membranes and encapsulated catalysts, such as ribozymes, may have acted in conjunction with each other, enabling otherwise-impossible chemical transformations within primordial cells. Early cells likely consisted of fatty acid vesicles enclosing magnesium-dependent ribozymes. Here, the authors show that fatty acid derivatives can form vesicles that, unlike those formed from only unmodified fatty acids, are stable in the presence of magnesium and could support ribozyme catalysis.
Collapse
Affiliation(s)
- Katarzyna P Adamala
- Howard Hughes Medical Institute and Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, USA
| | - Aaron E Engelhart
- Howard Hughes Medical Institute and Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, USA
| | - Jack W Szostak
- Howard Hughes Medical Institute and Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, Massachusetts 02114, USA
| |
Collapse
|
35
|
Murillo-Sánchez S, Beaufils D, González Mañas JM, Pascal R, Ruiz-Mirazo K. Fatty acids' double role in the prebiotic formation of a hydrophobic dipeptide. Chem Sci 2016; 7:3406-3413. [PMID: 29997836 PMCID: PMC6007129 DOI: 10.1039/c5sc04796j] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 02/09/2016] [Indexed: 02/06/2023] Open
Abstract
In search of a connection between prebiotic peptide chemistry and lipid compartments, the reaction of a 5(4H)-oxazolone with leucinamide was extensively explored under buffered aqueous conditions, where diverse amphiphiles and surfactants could form supramolecular assemblies. Significant increases in yield and changes in stereoselectivity were observed when fatty acids exceeded their critical aggregation concentration, self-assembling into vesicles in particular. This effect does not take place below the fatty acid solubility limit, or when other anionic amphiphiles/surfactants are used. Data from fluorimetric and Langmuir trough assays, complementary to the main HPLC results reported here, demonstrate that the dipeptide product co-localizes with fatty acid bilayers and monolayers. Additional experiments in organic solvents suggest that acid-base catalysis operates at the water-aggregate interface, linked to the continuous proton exchange dynamics that fatty acids undergo at pH values around their effective pKa. These simple amphiphiles could therefore play a dual role as enhancers of peptide chemistry under prebiotic conditions, providing soft and hydrophobic organic domains through self-assembly and actively inducing catalysis at their interface with the aqueous environment. Our results support a systems chemistry approach to life's origin.
Collapse
Affiliation(s)
| | - Damien Beaufils
- Institut des Biomolécules Max Mousseron (IBMM, UMR 5247, CNRS/Université de Montpellier/ENSCM) , Montpellier , France .
| | | | - Robert Pascal
- Institut des Biomolécules Max Mousseron (IBMM, UMR 5247, CNRS/Université de Montpellier/ENSCM) , Montpellier , France .
| | - Kepa Ruiz-Mirazo
- Biophysics Unit (CSIC, UPV/EHU) , University of the Basque Country , Spain . .,Department of Logic and Philosophy of Science , University of the Basque Country , Spain
| |
Collapse
|
36
|
Rapf RJ, Vaida V. Sunlight as an energetic driver in the synthesis of molecules necessary for life. Phys Chem Chem Phys 2016; 18:20067-84. [DOI: 10.1039/c6cp00980h] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
This review considers how photochemistry and sunlight-driven reactions can abiotically generate prebiotic molecules necessary for the evolution of life.
Collapse
Affiliation(s)
- Rebecca J. Rapf
- Department of Chemistry and Biochemistry
- CIRES
- University of Colorado at Boulder
- Boulder
- USA
| | - Veronica Vaida
- Department of Chemistry and Biochemistry
- CIRES
- University of Colorado at Boulder
- Boulder
- USA
| |
Collapse
|
37
|
Budin I, Prwyes N, Zhang N, Szostak JW. Chain-length heterogeneity allows for the assembly of fatty acid vesicles in dilute solutions. Biophys J 2015; 107:1582-90. [PMID: 25296310 PMCID: PMC4190651 DOI: 10.1016/j.bpj.2014.07.067] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 07/24/2014] [Accepted: 07/30/2014] [Indexed: 12/03/2022] Open
Abstract
A requirement for concentrated and chemically homogeneous pools of molecular building blocks would severely restrict plausible scenarios for the origin of life. In the case of membrane self-assembly, models of prebiotic lipid synthesis yield primarily short, single-chain amphiphiles that can form bilayer vesicles only at very high concentrations. These high critical aggregation concentrations (cacs) pose significant obstacles for the self-assembly of single-chain lipid membranes. Here, we examine membrane self-assembly in mixtures of fatty acids with varying chain lengths, an expected feature of any abiotic lipid synthesis. We derive theoretical predictions for the cac of mixtures by adapting thermodynamic models developed for the analogous phenomenon of mixed micelle self-assembly. We then use several complementary methods to characterize aggregation experimentally, and find cac values in close agreement with our theoretical predictions. These measurements establish that the cac of fatty acid mixtures is dramatically lowered by minor fractions of long-chain species, thereby providing a plausible route for protocell membrane assembly. Using an NMR-based approach to monitor aggregation of isotopically labeled samples, we demonstrate the incorporation of individual components into mixed vesicles. These experiments suggest that vesicles assembled in dilute, mixed solutions are depleted of the shorter-chain-length lipid species, a finding that carries implications for the composition of primitive cell membranes.
Collapse
Affiliation(s)
- Itay Budin
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, Massachusetts; Miller Institute for Basic Research in Science, University of California, Berkeley, Berkeley, California
| | - Noam Prwyes
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, Massachusetts
| | - Na Zhang
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, Massachusetts; High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, P. R. China
| | - Jack W Szostak
- Howard Hughes Medical Institute, Department of Molecular Biology and Center for Computational and Integrative Biology, Massachusetts General Hospital, Boston, Massachusetts.
| |
Collapse
|
38
|
|
39
|
Current Ideas about Prebiological Compartmentalization. Life (Basel) 2015; 5:1239-63. [PMID: 25867709 PMCID: PMC4500137 DOI: 10.3390/life5021239] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 04/01/2015] [Accepted: 04/02/2015] [Indexed: 01/17/2023] Open
Abstract
Contemporary biological cells are highly sophisticated dynamic compartment systems which separate an internal volume from the external medium through a boundary, which controls, in complex ways, the exchange of matter and energy between the cell's interior and the environment. Since such compartmentalization is a fundamental principle of all forms of life, scenarios have been elaborated about the emergence of prebiological compartments on early Earth, in particular about their likely structural characteristics and dynamic features. Chemical systems that consist of potentially prebiological compartments and chemical reaction networks have been designed to model pre-cellular systems. These systems are often referred to as "protocells". Past and current protocell model systems are presented and compared. Since the prebiotic formation of cell-like compartments is directly linked to the prebiotic availability of compartment building blocks, a few aspects on the likely chemical inventory on the early Earth are also summarized.
Collapse
|
40
|
Xu W, Zhang H, Dong S, Hao J. (133)Cs NMR and molecular dynamics simulation on bilayers of Cs(+) ion binding to aggregates of fatty acid soap at high pH. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:11567-11573. [PMID: 25255857 DOI: 10.1021/la503193h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Fatty acid bilayers are usually formed due to the hydrogen bonds between the protonated carboxyl (-COOH) and the deprotonated carboxylate (-COO(-)). Therefore, the formation of the bilayers must be at the pH around the pKa of the fatty acid, which is a narrow pH range (mostly about 7-9). Fatty acid bilayers can be used as cell membrane model but the narrow pH range largely limits their applications. Herein, fatty acid bilayers were first detected at high pH (>13) in the stearic acid (SA)/CsOH/H2O system, which is not consistent with the explanation of the traditional hydrogen bond theory for fatty acid bilayers around pH. Cryogenic transmission electron microscopy (cryo-TEM) images, X-ray diffraction (XRD) patterns, and deuterium nuclear magnetic resonance ((2)H NMR) spectra demonstrate the planar sheet bilayers. The pH, conductivity, and (133)Cs NMR data indicate the strong interaction between Cs(+) and the bilayers. Rheological characterizations reflect the viscoelasticity of the Lα phase sample of bilayers. Molecular dynamics simulation increases the reliability of our observations. The assumed growth process of the aggregates and the detailed arrangement of the Cs(+) on the bilayers were proposed according to the experimental data and the molecular dynamics simulation. This work will promote the application scope of fatty acid bilayers with wide pH range.
Collapse
Affiliation(s)
- Wenlong Xu
- Key Laboratory of Colloid and Interface Chemistry, Shandong University , Ministry of Education, Jinan 250100, P. R. China
| | | | | | | |
Collapse
|
41
|
Wamberg MC, Wieczorek R, Brier SB, de Vries JW, Kwak M, Herrmann A, Monnard PA. Functionalization of fatty acid vesicles through newly synthesized bolaamphiphile-DNA conjugates. Bioconjug Chem 2014; 25:1678-88. [PMID: 25144926 DOI: 10.1021/bc500289u] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The surface functionalization of fatty acid vesicles will allow their use as nanoreactors for complex chemistry. In this report, the tethering of several DNA conjugates to decanoic acid vesicles for molecular recognition and synthetic purposes was explored. Due to the highly dynamic nature of these structures, only one novel bola-amphiphile DNA conjugate could interact efficiently with or spontaneously pierce into the vesicle bilayers without jeopardizing their self-assembly or stability. This molecule was synthesized via a Cu(I)-catalyzed [3 + 2] azide-alkyne cycloaddition (click reaction), and consists of a single hydrocarbon chain of 20 carbons having on one end a triazole group linked to the 5'-phosphate of the nucleic acid and on the other side a hydroxyl-group. Its insertion was so effective that a fluorescent label on the DNA complementary to the conjugate could be used to visualize fatty acid structures.
Collapse
Affiliation(s)
- Michael C Wamberg
- Center for Fundamental Living Technology (FLinT), Department of Physics, Chemistry and Pharmacy, University of Southern Denmark , Campusvej 55, DK-5230 Odense M, Denmark
| | | | | | | | | | | | | |
Collapse
|
42
|
Shirt-Ediss B, Ruiz-Mirazo K, Mavelli F, Solé RV. Modelling lipid competition dynamics in heterogeneous protocell populations. Sci Rep 2014; 4:5675. [PMID: 25024020 PMCID: PMC4097352 DOI: 10.1038/srep05675] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Accepted: 05/19/2014] [Indexed: 02/02/2023] Open
Abstract
Recent experimental work in the field of synthetic protocell biology has shown that prebiotic vesicles are able to 'steal' lipids from each other. This phenomenon is driven purely by asymmetries in the physical state or composition of the vesicle membranes, and, when lipid resource is limited, translates directly into competition amongst the vesicles. Such a scenario is interesting from an origins of life perspective because a rudimentary form of cell-level selection emerges. To sharpen intuition about possible mechanisms underlying this behaviour, experimental work must be complemented with theoretical modelling. The aim of this paper is to provide a coarse-grain mathematical model of protocell lipid competition. Our model is capable of reproducing, often quantitatively, results from core experimental papers that reported distinct types vesicle competition. Additionally, we make some predictions untested in the lab, and develop a general numerical method for quickly solving the equilibrium point of a model vesicle population.
Collapse
Affiliation(s)
- Ben Shirt-Ediss
- ICREA-Complex Systems Lab, Institut de Biologia Evolutiva, CSIC-UPF, Barcelona, Spain
- Logic and Philosophy of Science Department, University of The Basque Country, Spain
| | - Kepa Ruiz-Mirazo
- Logic and Philosophy of Science Department, University of The Basque Country, Spain
- Biophysics Unit (CSIC-UPV/EHU), University of The Basque Country, Spain
| | | | - Ricard V. Solé
- ICREA-Complex Systems Lab, Institut de Biologia Evolutiva, CSIC-UPF, Barcelona, Spain
- Santa Fe Institute, 1399 Hyde Park Road, Santa Fe NM 87501, USA
| |
Collapse
|
43
|
Albertsen A, Duffy C, Sutherland J, Monnard PA. Self-assembly of phosphate amphiphiles in mixtures of prebiotically plausible surfactants. ASTROBIOLOGY 2014; 14:462-472. [PMID: 24885934 PMCID: PMC4060816 DOI: 10.1089/ast.2013.1111] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 03/10/2014] [Indexed: 06/01/2023]
Abstract
The spontaneous formation of closed bilayer structures from prebiotically plausible amphiphiles is an essential requirement for the emergence of early cells on prebiotic Earth. The sources of amphiphiles could have been both endo- and exogenous (accretion of meteorite carbonaceous material or interstellar dust particles). Among all prebiotic possible amphiphile candidates, those containing phosphate are the least investigated species because their self-assembly occurs in a seemingly too narrow range of conditions. The self-assembly of simple phosphate amphiphiles should, however, be of great interest, as contemporary membranes predominantly contain phospholipids. In contrast to common expectations, we show that these amphiphiles can be easily synthesized under prebiotically plausible environmental conditions and can efficiently form bilayer structures in the presence of various co-surfactants across a large range of pH values. Vesiculation was even observed in crude reaction mixtures that contained 1-decanol as the amphiphile precursor. The two best co-surfactants promoted vesicle formation over the entire pH range in aqueous solutions. Expanding the pH range where bilayer membranes self-assemble and remain intact is a prerequisite for the emergence of early cell-like compartments and their preservation under fluctuating environmental conditions. These mixed bilayers also retained small charged solutes, such as dyes. These results demonstrate that alkyl phosphate amphiphiles might have played a significant role as early compartment building blocks.
Collapse
Affiliation(s)
- A.N. Albertsen
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense, Denmark
| | - C.D. Duffy
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | | | - P.-A. Monnard
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense, Denmark
| |
Collapse
|
44
|
Tamulis A, Grigalavicius M. Quantum entanglement in photoactive prebiotic systems. SYSTEMS AND SYNTHETIC BIOLOGY 2014; 8:117-40. [PMID: 24799958 DOI: 10.1007/s11693-014-9138-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 03/07/2014] [Accepted: 03/11/2014] [Indexed: 11/28/2022]
Abstract
This paper contains the review of quantum entanglement investigations in living systems, and in the quantum mechanically modelled photoactive prebiotic kernel systems. We define our modelled self-assembled supramolecular photoactive centres, composed of one or more sensitizer molecules, precursors of fatty acids and a number of water molecules, as a photoactive prebiotic kernel systems. We propose that life first emerged in the form of such minimal photoactive prebiotic kernel systems and later in the process of evolution these photoactive prebiotic kernel systems would have produced fatty acids and covered themselves with fatty acid envelopes to become the minimal cells of the Fatty Acid World. Specifically, we model self-assembling of photoactive prebiotic systems with observed quantum entanglement phenomena. We address the idea that quantum entanglement was important in the first stages of origins of life and evolution of the biospheres because simultaneously excite two prebiotic kernels in the system by appearance of two additional quantum entangled excited states, leading to faster growth and self-replication of minimal living cells. The quantum mechanically modelled possibility of synthesizing artificial self-reproducing quantum entangled prebiotic kernel systems and minimal cells also impacts the possibility of the most probable path of emergence of protocells on the Earth or elsewhere. We also examine the quantum entangled logic gates discovered in the modelled systems composed of two prebiotic kernels. Such logic gates may have application in the destruction of cancer cells or becoming building blocks of new forms of artificial cells including magnetically active ones.
Collapse
Affiliation(s)
- Arvydas Tamulis
- Institute of Theoretical Physics and Astronomy, Vilnius University, A. Gostauto 12, Vilnius, Lithuania
| | - Mantas Grigalavicius
- Department of Radiation Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Ullernchausseen 70, Oslo, Norway
| |
Collapse
|
45
|
Olasagasti F, Maurel MC, Deamer D. Physico-chemical interactions between compartment-forming lipids and other prebiotically relevant biomolecules. BIO WEB OF CONFERENCES 2014. [DOI: 10.1051/bioconf/20140205001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
|
46
|
Ahmad N, Muhammad R, Tajuddin HA, Misran M. Effect of glycolipids on the stability and electrophoretic mobility of decanoic acid vesicles. Colloids Surf A Physicochem Eng Asp 2014. [DOI: 10.1016/j.colsurfa.2013.10.045] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
47
|
Tamulis A, Grigalavicius M, Baltrusaitis J. Phenomenon of quantum entanglement in a system composed of two minimal protocells. ORIGINS LIFE EVOL B 2013; 43:49-66. [PMID: 23242832 DOI: 10.1007/s11084-012-9323-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Accepted: 10/31/2012] [Indexed: 10/27/2022]
Abstract
The quantum mechanical self-assembly of two separate photoactive supramolecular systems with different photosynthetic centers was investigated by means of density functional theory methods. Quantum entangled energy transitions from one subsystem to the other and the assembly of logically controlled artificial minimal protocells were modeled. The systems studied were based on different photoactive sensitizer molecules covalently bonded to a non-canonical oxo-guanine::cytosine supramolecule with the precursor of a fatty acid (pFA) molecule attached via Van der Waals forces, all surrounded by water molecules. The electron correlation interactions responsible for the weak hydrogen and Van der Waals chemical bonds increased due to the addition of polar water solvent molecules. The distances between the separated sensitizer, nucleotide, pFA, and water molecules are comparable to Van der Waals and hydrogen bonding radii. As a result, the overall system becomes compressed, resulting in photo-excited electron tunneling from the sensitizer (bis(4-diphenylamine-2-phenyl)-squarine or 1,4-bis(N,N-dimethylamino)naphthalene) to the pFA molecules. Absorption spectra as well as electron transfer trajectories associated with the different excited states were calculated using time dependent density functional theory methods. The results allow separation of the quantum entangled photosynthetic transitions within the same minimal protocell and with the neighboring minimal protocell. The transferred electron is used to cleave a "waste" organic molecule resulting in the formation of the desired product. A two variable, quantum entangled AND logic gate was proposed, consisting of two input photoactive sensitizer molecules and one output (pFA molecule). It is proposed that a similar process might be applied for the destruction of tumor cancer cells or to yield building blocks in artificial cells.
Collapse
Affiliation(s)
- Arvydas Tamulis
- Vilnius University Institute of Theoretical Physics and Astronomy, A. Gostauto 12, Vilnius, Lithuania.
| | | | | |
Collapse
|
48
|
Groen J, Deamer DW, Kros A, Ehrenfreund P. Polycyclic aromatic hydrocarbons as plausible prebiotic membrane components. ORIGINS LIFE EVOL B 2012; 42:295-306. [PMID: 22798228 PMCID: PMC3427487 DOI: 10.1007/s11084-012-9292-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2012] [Accepted: 06/21/2012] [Indexed: 12/02/2022]
Abstract
Aromatic molecules delivered to the young Earth during the heavy bombardment phase in the early history of our solar system were likely to be among the most abundant and stable organic compounds available. The Aromatic World hypothesis suggests that aromatic molecules might function as container elements, energy transduction elements and templating genetic components for early life forms. To investigate the possible role of aromatic molecules as container elements, we incorporated different polycyclic aromatic hydrocarbons (PAH) in the membranes of fatty acid vesicles. The goal was to determine whether PAH could function as a stabilizing agent, similar to the role that cholesterol plays in membranes today. We studied vesicle size distribution, critical vesicle concentration and permeability of the bilayers using C6-C10 fatty acids mixed with amphiphilic PAH derivatives such as 1-hydroxypyrene, 9-anthracene carboxylic acid and 1,4 chrysene quinone. Dynamic Light Scattering (DLS) spectroscopy was used to measure the size distribution of vesicles and incorporation of PAH species was established by phase-contrast and epifluorescence microscopy. We employed conductimetric titration to determine the minimal concentration at which fatty acids could form stable vesicles in the presence of PAHs. We found that oxidized PAH derivatives can be incorporated into decanoic acid (DA) vesicle bilayers in mole ratios up to 1:10 (PAH:DA). Vesicle size distribution and critical vesicle concentration were largely unaffected by PAH incorporation, but 1-hydroxypyrene and 9-anthracene carboxylic acid lowered the permeability of fatty acid bilayers to small solutes up to 4-fold. These data represent the first indication of a cholesterol-like stabilizing effect of oxidized PAH derivatives in a simulated prebiotic membrane.
Collapse
Affiliation(s)
- Joost Groen
- Leiden Institute of Chemistry, Leiden University, 2333 CC Leiden, The Netherlands.
| | | | | | | |
Collapse
|
49
|
Piedrafita G, Ruiz-Mirazo K, Monnard PA, Cornish-Bowden A, Montero F. Viability conditions for a compartmentalized protometabolic system: a semi-empirical approach. PLoS One 2012; 7:e39480. [PMID: 22761803 PMCID: PMC3384665 DOI: 10.1371/journal.pone.0039480] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2012] [Accepted: 05/24/2012] [Indexed: 11/18/2022] Open
Abstract
In this work we attempt to find out the extent to which realistic prebiotic compartments, such as fatty acid vesicles, would constrain the chemical network dynamics that could have sustained a minimal form of metabolism. We combine experimental and simulation results to establish the conditions under which a reaction network with a catalytically closed organization (more specifically, an (M,R-system) would overcome the potential problem of self-suffocation that arises from the limited accessibility of nutrients to its internal reaction domain. The relationship between the permeability of the membrane, the lifetime of the key catalysts and their efficiency (reaction rate enhancement) turns out to be critical. In particular, we show how permeability values constrain the characteristic time scale of the bounded protometabolic processes. From this concrete and illustrative example we finally extend the discussion to a wider evolutionary context.
Collapse
Affiliation(s)
- Gabriel Piedrafita
- Departamento de Bioquímica y Biología Molecular I, Universidad Complutense de Madrid, Madrid, Spain
| | - Kepa Ruiz-Mirazo
- Departamento de Lógica y Filosofía de la Ciencia, Universidad del País Vasco, Donostia-San Sebastián, Spain
- Unidad de Biofísica, Consejo Superior de Investigaciones Científicas-Universidad del País Vasco, Leioa, Spain
| | - Pierre-Alain Monnard
- Center for Fundamental Living Technology, University of Southern Denmark, Odense, Denmark
| | - Athel Cornish-Bowden
- Unité de Bioénergétique et Ingénierie des Protéines, Centre National de la Recherche Scientifique, Marseille, France
| | - Francisco Montero
- Departamento de Bioquímica y Biología Molecular I, Universidad Complutense de Madrid, Madrid, Spain
| |
Collapse
|
50
|
Photochemically driven redox chemistry induces protocell membrane pearling and division. Proc Natl Acad Sci U S A 2012; 109:9828-32. [PMID: 22665773 DOI: 10.1073/pnas.1203212109] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Prior to the evolution of complex biochemical machinery, the growth and division of simple primitive cells (protocells) must have been driven by environmental factors. We have previously demonstrated two pathways for fatty acid vesicle growth in which initially spherical vesicles grow into long filamentous vesicles; division is then mediated by fluid shear forces. Here we describe a different pathway for division that is independent of external mechanical forces. We show that the illumination of filamentous fatty acid vesicles containing either a fluorescent dye in the encapsulated aqueous phase, or hydroxypyrene in the membrane, rapidly induces pearling and subsequent division in the presence of thiols. The mechanism of this photochemically driven pathway most likely involves the generation of reactive oxygen species, which oxidize thiols to disulfide-containing compounds that associate with fatty acid membranes, inducing a change in surface tension and causing pearling and subsequent division. This vesicle division pathway provides an alternative route for the emergence of early self-replicating cell-like structures, particularly in thiol-rich surface environments where UV-absorbing polycyclic aromatic hydrocarbons (PAHs) could have facilitated protocell division. The subsequent evolution of cellular metabolic processes controlling the thiol:disulfide redox state would have enabled autonomous cellular control of the timing of cell division, a major step in the origin of cellular life.
Collapse
|