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Kim KE, Balaj RV, Zarzar LD. Chemical Programming of Solubilizing, Nonequilibrium Active Droplets. Acc Chem Res 2024; 57:2372-2382. [PMID: 39116001 DOI: 10.1021/acs.accounts.4c00299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/10/2024]
Abstract
ConspectusThe multifunctionality and resilience of living systems has inspired an explosion of interest in creating materials with life-like properties. Just as life persists out-of-equilibrium, we too should try to design materials that are thermodynamically unstable but can be harnessed to achieve desirable, adaptive behaviors. Studying minimalistic chemical systems that exhibit relatively simple emergent behaviors, such as motility, communication, or self-organization, can provide insight into fundamental principles which may enable the design of more complex and life-like synthetic materials in the future.Emulsions, which are composed of liquid droplets dispersed in another immiscible fluid phase, have emerged as fascinating chemically minimal materials in which to study nonequilibrium, life-like properties. As covered in this Account, our group has focused on studying oil-in-water emulsions, specifically those which destabilize by solubilization, a process wherein oil is released into the continuous phase over time to create gradients of oil-filled micelles. These chemical gradients can create interfacial tension gradients that lead to droplet self-propulsion as well as mediate communication between neighboring oil droplets. As such, oil-in-water emulsions present an interesting platform for studying active matter. However, despite being chemically minimal with sometimes as few as three chemicals (oil, water, and a surfactant), emulsions present surprising complexity across the molecular to macroscale. Fundamental processes governing their active behavior, such as micelle-mediated interfacial transport, are still not well understood. This complexity is compounded by the challenges of studying systems out-of-equilibrium which typically require new analytical methods and may break our intuition derived from equilibrium thermodynamics.In this Account, we highlight our group's efforts toward developing chemical frameworks for understanding active and interactive oil-in-water emulsions. How do the chemical properties and physical spatial organization of the oil, water, and surfactant combine to yield colloidal-scale active properties? Our group tackles this question by employing systematic studies of active behavior working across the chemical space of oils and surfactants to link molecular structure to active behavior. The Account begins with an introduction to the self-propulsion of single, isolated droplets and how by applying biases, such as with a gravitational field or interfacially adsorbed particles, drop speeds can be manipulated. Next, we illustrate that some droplets can be attractive, as well as self-propulsive/repulsive, which does not fall in line with the current understanding of the impact of oil-filled micelle gradients on interfacial tensions. The mechanisms by which oil-filled micelles influence interfacial tensions of nonequilibrium interfaces is poorly understood and requires deeper molecular understanding. Regardless, we extend our knowledge of droplet motility to design emulsions with nonreciprocal predator-prey interactions and describe the dynamic self-organization that arises from the combination of reciprocal and nonreciprocal interactions between droplets. Finally, we highlight our group's progress toward answering key chemical questions surrounding nonequilibrium processes in emulsions that remain to be answered. We hope that our progress in understanding the chemical principles governing the dynamic nonequilibrium properties of oil-in-water droplets can help inform research in tangential research areas such as cell biology and origins of life.
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Affiliation(s)
- Kueyoung E Kim
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16082, United States
| | - Rebecca V Balaj
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16082, United States
| | - Lauren D Zarzar
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16082, United States
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16082, United States
- Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16082, United States
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Dai S, Xie Z, Wang B, Ye R, Ou X, Wang C, Yu N, Huang C, Zhao J, Cai C, Zhang F, Buratto D, Khan T, Qiao Y, Hua Y, Zhou R, Tian B. An inorganic mineral-based protocell with prebiotic radiation fitness. Nat Commun 2023; 14:7699. [PMID: 38052788 DOI: 10.1038/s41467-023-43272-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 11/06/2023] [Indexed: 12/07/2023] Open
Abstract
Protocell fitness under extreme prebiotic conditions is critical in understanding the origin of life. However, little is known about protocell's survival and fitness under prebiotic radiations. Here we present a radioresistant protocell model based on assembly of two types of coacervate droplets, which are formed through interactions of inorganic polyphosphate (polyP) with divalent metal cation and cationic tripeptide, respectively. Among the coacervate droplets, only the polyP-Mn droplet is radiotolerant and provides strong protection for recruited proteins. The radiosensitive polyP-tripeptide droplet sequestered with both proteins and DNA could be encapsulated inside the polyP-Mn droplet, and form into a compartmentalized protocell. The protocell protects the inner nucleoid-like condensate through efficient reactive oxygen species' scavenging capacity of intracellular nonenzymic antioxidants including Mn-phosphate and Mn-peptide. Our results demonstrate a radioresistant protocell model with redox reaction system in response to ionizing radiation, which might enable the protocell fitness to prebiotic radiation on the primitive Earth preceding the emergence of enzyme-based fitness. This protocell might also provide applications in synthetic biology as bioreactor or drug delivery system.
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Affiliation(s)
- Shang Dai
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China
- Shanghai Institute for Advanced Study of Zhejiang University, Shanghai, China
| | - Zhenming Xie
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Binqiang Wang
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Rui Ye
- School of Physics, Institute of Quantitative Biology, Zhejiang University, Hangzhou, China
| | - Xinwen Ou
- School of Physics, Institute of Quantitative Biology, Zhejiang University, Hangzhou, China
| | - Chen Wang
- College of Pharmaceutical Science, Zhejiang University, Hangzhou, China
| | - Ning Yu
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Cheng Huang
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Jie Zhao
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Chunhui Cai
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Furong Zhang
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Damiano Buratto
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China
- School of Physics, Institute of Quantitative Biology, Zhejiang University, Hangzhou, China
| | - Taimoor Khan
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China
- School of Physics, Institute of Quantitative Biology, Zhejiang University, Hangzhou, China
| | - Yan Qiao
- Institute of Chemistry, Chinese Academy of Sciences, Beijing, China.
| | - Yuejin Hua
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China.
- Qian Xuesen Collaborative Research Center of Astrochemistry and Space Life Sciences, Ningbo University, Ningbo, China.
- Cancer Center, Zhejiang University, Hangzhou, China.
| | - Ruhong Zhou
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China.
- Shanghai Institute for Advanced Study of Zhejiang University, Shanghai, China.
- School of Physics, Institute of Quantitative Biology, Zhejiang University, Hangzhou, China.
- Cancer Center, Zhejiang University, Hangzhou, China.
| | - Bing Tian
- Institute of Biophysics, College of Life Sciences, Zhejiang University, Hangzhou, China.
- Cancer Center, Zhejiang University, Hangzhou, China.
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Jia TZ, Wang PH, Niwa T, Mamajanov I. Connecting primitive phase separation to biotechnology, synthetic biology, and engineering. J Biosci 2021; 46:79. [PMID: 34373367 PMCID: PMC8342986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
One aspect of the study of the origins of life focuses on how primitive chemistries assembled into the first cells on Earth and how these primitive cells evolved into modern cells. Membraneless droplets generated from liquid-liquid phase separation (LLPS) are one potential primitive cell-like compartment; current research in origins of life includes study of the structure, function, and evolution of such systems. However, the goal of primitive LLPS research is not simply curiosity or striving to understand one of life's biggest unanswered questions, but also the possibility to discover functions or structures useful for application in the modern day. Many applicational fields, including biotechnology, synthetic biology, and engineering, utilize similar phaseseparated structures to accomplish specific functions afforded by LLPS. Here, we briefly review LLPS applied to primitive compartment research and then present some examples of LLPS applied to biomolecule purification, drug delivery, artificial cell construction, waste and pollution management, and flavor encapsulation. Due to a significant focus on similar functions and structures, there appears to be much for origins of life researchers to learn from those working on LLPS in applicational fields, and vice versa, and we hope that such researchers can start meaningful cross-disciplinary collaborations in the future.
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Affiliation(s)
- Tony Z Jia
- grid.32197.3e0000 0001 2179 2105Earth-Life Science Institute, Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo, 152-8550 Japan ,grid.482804.2Blue Marble Space Institute of Science, 1001 4th Ave., Suite 3201, Seattle, Washington 98154 USA
| | - Po-Hsiang Wang
- grid.32197.3e0000 0001 2179 2105Earth-Life Science Institute, Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo, 152-8550 Japan ,grid.37589.300000 0004 0532 3167Graduate Institute of Environmental Engineering, National Central University, Zhongli Dist, 300 Zhongda Rd, Taoyuan City, 32001 Taiwan
| | - Tatsuya Niwa
- grid.32197.3e0000 0001 2179 2105Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Nagatsuta-cho 4259, Midori-ku, Yokohama, 226-8503 Japan
| | - Irena Mamajanov
- grid.32197.3e0000 0001 2179 2105Earth-Life Science Institute, Tokyo Institute of Technology, 2-12-1-IE-1 Ookayama, Meguro-ku, Tokyo, 152-8550 Japan
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Tiwari P, Bharti I, Bohidar HB, Quadir S, Joshi MC, Arfin N. Complex Coacervation and Overcharging during Interaction between Hydrophobic Zein and Hydrophilic Laponite in Aqueous Ethanol Solution. ACS OMEGA 2020; 5:33064-33074. [PMID: 33403268 PMCID: PMC7774070 DOI: 10.1021/acsomega.0c04647] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Accepted: 12/04/2020] [Indexed: 06/12/2023]
Abstract
In this paper, for the first time, we have reported the formation of complex coacervate during interaction between hydrophobic protein, zein, and hydrophilic nanoclay, Laponite, in a 60% v/v ethanol solution at pH 4. Dynamic light scattering and viscosity measurements revealed the formation of zein-Laponite complexes during the interaction between zein at fixed concentration, C Z = 1 mg/mL, and varying concentrations of Laponite, C L (7.8 × 10-4 - 0.25% w/v). Further investigation of the zein-Laponite complexes using turbidity and zeta potential data showed that these complexes could be demarcated in three different regions: Region I, below the charge neutralization region (C Z = 1 mg/mL, C L ≤ 0.00625% w/v) where soluble complexes was formed during interaction between oppositely charged zein and Laponite; Region II, the charge neutralization region (C Z = 1 mg/mL, 0.00625 < C L ≤ 0.05% w/v) where zein-Laponite complexes form neutral coacervates; and Region III, the interesting overcharged coacervates region (C Z = 1 mg/mL, C L > 0.05% w/v). Investigation of coacervates using a fluorescence imaging technique showed that the size of neutral coacervates in region II was large (mean size = 1223.7 nm) owing to aggregation as compared to the small size of coacervates (mean size = 464.7 nm) in region III owing to repulsion between overcharged coacervates. Differential scanning calorimeter, DSC, revealed the presence of an ample amount of bound water in region III. The presence of bound water was evident from the presence of an additional peak at 107 °C in region III apart from normal enthalpy of evaporation of water from coacervates.
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Affiliation(s)
- Preeti Tiwari
- Soft
condense matter laboratory, Centre for Interdisciplinary Research
In Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India
| | - Indu Bharti
- Soft
condense matter laboratory, Centre for Interdisciplinary Research
In Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India
| | - Himadri B Bohidar
- School
of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Shabina Quadir
- Multidisciplinary
Centre for Advanced Research and Studies, Jamia Millia Islamia, New Delhi 110025, India
| | - Mohan C Joshi
- Multidisciplinary
Centre for Advanced Research and Studies, Jamia Millia Islamia, New Delhi 110025, India
| | - Najmul Arfin
- Soft
condense matter laboratory, Centre for Interdisciplinary Research
In Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India
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Abstract
Liquid-liquid phase separation forms condensates that feature a highly concentrated liquid phase, a defined yet dynamic boundary, and dynamic exchange at and across the boundary. Phase transition drives the formation of dynamic multienzyme complexes in cells, for example, the purinosome, which forms subcellular macrobodies responsible for de novo purine biosynthesis. Here, we construct synthetic versions of multienzyme biosynthetic systems by assembling enzymes in protein condensates. A synthetic protein phase separation system using component proteins from postsynaptic density in neuronal synapses, GKAP, Shank, and Homer provides the scaffold for assembly. Three sets of guest proteins: a pair of fluorescent proteins (CFP and YFP), three sequential enzymes in menaquinone biosynthesis pathway (MenF, MenD, and MenH), and two enzymes in terpene biosynthesis pathway (Idi and IspA) are assembled via peptide-peptide interactions in the condensate. First, we discover that coassembly of CFP and YFP exhibited a broad distribution of the FRET signal within the condensate. Second, a spontaneous enrichment of the rate-limiting enzyme MenD in the condensate is sufficient to increase the 2-succinyl-6-hydroxy-2,4-cyclohexadiene-1-carboxylate production rate by 70%. Third, coassembly of both Idi and IspA in the protein condensate increases the farnesyl pyrophosphate production rate by more than 50%. Altogether, we show here that phase separation significantly accelerates the efficiency of multienzyme biocatalysis.
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Affiliation(s)
- Miao Liu
- Department of Chemistry, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Sicong He
- Department of Electronic and Computer Engineering, Center of Systems Biology and Human Health, School of Science and Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Lixin Cheng
- Department of Critical Care Medicine, Shenzhen People's Hospital, First Affiliated Hospital of Southern University of Science and Technology, Shenzhen 518000, China
| | - Jianan Qu
- Department of Electronic and Computer Engineering, Center of Systems Biology and Human Health, School of Science and Institute for Advanced Study, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, China
| | - Jiang Xia
- Department of Chemistry, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China.,Center for Cell & Developmental Biology, School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong SAR 02522, China
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Schreiber A, Huber MC, Schiller SM. Prebiotic Protocell Model Based on Dynamic Protein Membranes Accommodating Anabolic Reactions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:9593-9610. [PMID: 31287709 DOI: 10.1021/acs.langmuir.9b00445] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The nature of the first prebiotic compartments and their possible minimal molecular composition is of great importance in the origin of life scenarios. Current protocell model membranes are proposed to be lipid-based. This paradigm has several shortcomings such as limited membrane stability of monoacyl lipid-based membranes (e.g., fatty acids), missing pathways to synthesize protocell membrane components (e.g., phospholipids) under early earth conditions, and the requirement for different classes of molecules for the formation of compartments and the catalysis of reactions. Amino acids on the other hand are known to arise and persist with remarkable abundance under early earth conditions since the fundamental Miller-Urey experiments. They were also postulated early to form protocellular structures, for example, proteinoid capsules. Here, we present a protocell model constituted by membranes assembled from amphiphilic proteins based on prebiotic amino acids. Self-assembled dynamic protein membrane-based compartments (PMBCs) are impressively stable and compatible with prevalent cellular membrane constituents forming protein-only or protein-lipid hybrid membranes. They can embed processes essential for extant living cells, such as enclosure of molecules, membrane fusion, phase separation, and complex biosynthetic elements from modern cells demonstrating "upward" compatibility. Our findings suggest that prebiotic PMBCs represent a new type of protocell as a possible ancestor of current lipid-based cells. The presented prebiotic PMBC model can be used to design artificial cells, important for the study of structural, catalytic, and evolutionary pathways related to the emergence of life.
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Affiliation(s)
- Andreas Schreiber
- Zentrum für Biosystemanalyse (ZBSA) , Albert-Ludwigs-Universität Freiburg , 7 Habsburgerstrasse 49 , D-79104 Freiburg , Germany
- Faculty of Biology , University of Freiburg , Schänzlestrasse 1 , D-79104 Freiburg , Germany
| | - Matthias C Huber
- Zentrum für Biosystemanalyse (ZBSA) , Albert-Ludwigs-Universität Freiburg , 7 Habsburgerstrasse 49 , D-79104 Freiburg , Germany
- Faculty of Biology , University of Freiburg , Schänzlestrasse 1 , D-79104 Freiburg , Germany
| | - Stefan M Schiller
- Zentrum für Biosystemanalyse (ZBSA) , Albert-Ludwigs-Universität Freiburg , 7 Habsburgerstrasse 49 , D-79104 Freiburg , Germany
- Faculty of Biology , University of Freiburg , Schänzlestrasse 1 , D-79104 Freiburg , Germany
- BIOSS Centre for Biological Signalling Studies , University of Freiburg , Schänzlestrasse 18 , D-79104 Freiburg , Germany
- IMTEK Department of Microsystems Engineering , University of Freiburg , Georges-Köhler-Allee 103 , D-79110 Freiburg , Germany
- Cluster of Excellence livMatS @ FIT-Freiburg Center for Interactive Materials and Bioinspired Technologies , University of Freiburg , Georges-Köhler-Allee 105 , D-79110 Freiburg , Germany
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8
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Matveev VV. Cell theory, intrinsically disordered proteins, and the physics of the origin of life. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2019; 149:114-130. [PMID: 30965040 DOI: 10.1016/j.pbiomolbio.2019.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 04/01/2019] [Accepted: 04/05/2019] [Indexed: 12/30/2022]
Abstract
Cell theory, as formulated by Theodor Schwann in 1839, introduced the idea that the cell is the main structural unit of living nature. Later, in solving the problem of cell multiplication, Rudolf Virchow expanded the cell theory with a postulate: all cells only arise from pre-existing cells. But what did the very first cell arise from? This paper proposes extending the Virchow's law by the assumption that between the nonliving protocell and the first living cell the continuity of fundamental physical properties (the principle of invariance of physical properties) is preserved. The protocell is understood here as a cell-shaped physical system on the basis of the self-organized biologically significant prebiotic macromolecules, primarily peptides, having a potential to transform into the living cell. Biophase is considered as the physical basis of the membraneless protocell, the internal environment of which is separated from the external environment due to the phase of adsorbed water. The evidence is given that the first protocells may have been formed on the basis of intrinsically disordered peptides. Data on the similarity of the physical properties of living cells and the following model systems are given: protein and artificial polymer solutions, coacervate droplets, and ion-exchange resin granules. Available data on the similarity of the physical properties of cell models and living cells allow us to rephrase the Virchow's postulate as follows: the physical properties of a living cell could only arise from pre-existing physical properties of the protocell.
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Affiliation(s)
- Vladimir V Matveev
- Laboratory of Cell Physiology, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Ave 4, St. Petersburg, 194064, Russia.
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Poudyal RR, Guth-Metzler RM, Veenis AJ, Frankel EA, Keating CD, Bevilacqua PC. Template-directed RNA polymerization and enhanced ribozyme catalysis inside membraneless compartments formed by coacervates. Nat Commun 2019; 10:490. [PMID: 30700721 PMCID: PMC6353945 DOI: 10.1038/s41467-019-08353-4] [Citation(s) in RCA: 159] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 01/02/2019] [Indexed: 11/17/2022] Open
Abstract
Membraneless compartments, such as complex coacervates, have been hypothesized as plausible prebiotic micro-compartments due to their ability to sequester RNA; however, their compatibility with essential RNA World chemistries is unclear. We show that such compartments can enhance key prebiotically-relevant RNA chemistries. We demonstrate that template-directed RNA polymerization is sensitive to polycation identity, with polydiallyldimethylammonium chloride (PDAC) outperforming poly(allylamine), poly(lysine), and poly(arginine) in polycation/RNA coacervates. Differences in RNA diffusion rates between PDAC/RNA and oligoarginine/RNA coacervates imply distinct biophysical environments. Template-directed RNA polymerization is relatively insensitive to Mg2+ concentration when performed in PDAC/RNA coacervates as compared to buffer, even enabling partial rescue of the reaction in the absence of magnesium. Finally, we show enhanced activities of multiple nucleic acid enzymes including two ribozymes and a deoxyribozyme, underscoring the generality of this approach, in which functional nucleic acids like aptamers and ribozymes, and in some cases key cosolutes localize within the coacervate microenvironments. Membraneless compartments have been theorized to be prebiotic micro-compartments as they spontaneously encapsulate RNA and proteins. Here, the authors report membraneless compartments can enhance RNA chemistries, affecting template directed RNA polymerization and stimulating nucleic acid enzymes.
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Affiliation(s)
- Raghav R Poudyal
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA. .,Center for RNA Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA.
| | - Rebecca M Guth-Metzler
- Department of Biochemistry, Microbiology, and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA.,School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Andrew J Veenis
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA.,Center for RNA Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA
| | - Erica A Frankel
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA.,Center for RNA Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA.,The Dow Chemical Company, 400 Arcola Road, Collegeville, PA, 19426, USA
| | - Christine D Keating
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA.
| | - Philip C Bevilacqua
- Department of Chemistry, The Pennsylvania State University, University Park, PA, 16802, USA. .,Center for RNA Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA. .,Department of Biochemistry, Microbiology, and Molecular Biology, The Pennsylvania State University, University Park, PA, 16802, USA.
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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.
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11
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Vieregg JR, Tang TYD. Polynucleotides in cellular mimics: Coacervates and lipid vesicles. Curr Opin Colloid Interface Sci 2016. [DOI: 10.1016/j.cocis.2016.09.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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12
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Yang JZ, Min Wang, Ottenbrite RM. Synthesis of Copoly(amino acids) as Potential Biomaterials by Diphenyl Phosphoryl Azide. J BIOACT COMPAT POL 2016. [DOI: 10.1177/088391159300800105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A convenient chemical synthesis of copoly(amino acids) as poten tial biomaterials is described. Direct copolycondensations of α-amino acids us ing diphenyl phosphoryl azide (DPPA) as condensation agent were carried out in the presence of triethylamine (TEA) as a base. The amino acids used were β-benzyl-L-aspartate (Asp.Bz), γ-benzyl-L-glutamate (Glu.Bz), L-phenylalanine (Phe), and O-benzyl-L-tyrosine (Tyr.OBz). Copoly(amino acids) with weight- average molecular weights up to 28,000 were obtained in reasonable yields. Bimodal molecular weight distribution was observed in all the cases. Both the overall yield of the product and the yield of high molecular weight fraction are influenced by [DPPA]/[Monomer] and [TEA]/[Monomer] ratios. No significant solvent effect was observed.
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Affiliation(s)
- Jian-Zhong Yang
- Department of Chemistry Virginia Commonwealth University Richmond, VA 23284
| | - Min Wang
- Department of Chemistry Virginia Commonwealth University Richmond, VA 23284
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13
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Yang JZ, Wang M, Ottenbrite RM, Milstein S. Amino Acid Oligomer Microspheres as Drug Delivery Systems. II. Oligomerization of NCAs Initiated with L-Tyrosine Methyl Ester. J BIOACT COMPAT POL 2016. [DOI: 10.1177/088391159601100305] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Oligomerizations of various amino acid N-carboxyanhydrides (NCAs) were prepared in the presence of L-tyrosine methyl ester (Tyr.Me). Tyr.Me was found to be an efficient initiator to form oligopeptides consisting of L-aspartic acid, L-glutamic acid, L-phenylalanine, and L-tyrosine with random arrangements of amino acids. In acidic solution, the oligopeptides formed microspheres which were capable of encapsulating macromolecular drugs such as insulin and heparin. These microspheres were considered to be potential oral drug delivery systems.
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Affiliation(s)
- Jian-Zhong Yang
- Department of Chemistry, Virginia Commonwealth University, Richmond, Virginia 23284; Sharon Woods Technical Center, The Procter & Gamble Company, Cincinnati, Ohio 45241
| | | | | | - Sam Milstein
- Emishpere Technologies, Inc., 15 Skyline Drive, Hawthorne, New York
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14
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Amino Acid Oligomer Microspheres as Drug Delivery Systems. I. Synthesis of Oligo(Amino Acids) via NCAs and Their Microsphere Formation. J BIOACT COMPAT POL 2016. [DOI: 10.1177/088391159601100304] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Some thermally derived proteinoids are known to form hollow microspheres under specific conditions. In this study, oligomers consisting of L-aspartic acid, L-glutamic acid, L-phenylalanine, and L-tyrosine were prepared through the corresponding a-amino acid-N carboxyanhydrides (NCAs). The oligo(amino acids) synthesized by NCA method had better control on the composition as well as molecular weight. These oligo(amino acids) were found to spontaneously form microspheres under acidic conditions. It was also found that is possible to encapsulate a variety of drug entities within these unique self-assembling systems. The microspheres which form spontaneously at low pH's also dissolve in water at neutral pH and consequently have the potential to be used as oral drug delivery systems.
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15
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Egel R. Origins and emergent evolution of life: the colloid microsphere hypothesis revisited. ORIGINS LIFE EVOL B 2014; 44:87-110. [PMID: 25208738 DOI: 10.1007/s11084-014-9363-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 08/14/2014] [Indexed: 11/28/2022]
Abstract
Self-replicating molecules, in particular RNA, have long been assumed as key to origins of life on Earth. This notion, however, is not very secure since the reduction of life's complexity to self-replication alone relies on thermodynamically untenable assumptions. Alternative, earlier hypotheses about peptide-dominated colloid self-assembly should be revived. Such macromolecular conglomerates presumably existed in a dynamic equilibrium between confluent growth in sessile films and microspheres detached in turbulent suspension. The first organic syntheses may have been driven by mineral-assisted photoactivation at terrestrial geothermal fields, allowing photo-dependent heterotrophic origins of life. Inherently endowed with rudimentary catalyst activities, mineral-associated organic microstructures can have evolved adaptively toward cooperative 'protolife' communities, in which 'protoplasmic continuity' was maintained throughout a graded series of 'proto-biofilms', 'protoorganisms' and 'protocells' toward modern life. The proneness of organic microspheres to merge back into the bulk of sessile films by spontaneous fusion can have made large populations promiscuous from the beginning, which was important for the speed of collective evolution early on. In this protein-centered scenario, the emergent coevolution of uncoded peptides, metabolic cofactors and oligoribonucleotides was primarily optimized for system-supporting catalytic capabilities arising from nonribosomal peptide synthesis and nonreplicative ribonucleotide polymerization, which in turn incorporated other reactive micromolecular organics as vitamins and cofactors into composite macromolecular colloid films and microspheres. Template-dependent replication and gene-encoded protein synthesis emerged as secondary means for further optimization of overall efficieny later on. Eventually, Darwinian speciation of cell-like lineages commenced after minimal gene sets had been bundled in transmissible genomes from multigenomic protoorganisms.
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Affiliation(s)
- Richard Egel
- Department of Biology, University of Copenhagen Biocenter, Ole Maaløes Vej 5, DK-2200, Copenhagen, Denmark,
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16
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Jia TZ, Hentrich C, Szostak JW. Rapid RNA exchange in aqueous two-phase system and coacervate droplets. ORIGINS LIFE EVOL B 2014; 44:1-12. [PMID: 24577897 PMCID: PMC4141154 DOI: 10.1007/s11084-014-9355-8] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 01/31/2014] [Indexed: 11/24/2022]
Abstract
Compartmentalization in a prebiotic setting is an important aspect of early cell formation and is crucial for the development of an artificial protocell system that effectively couples genotype and phenotype. Aqueous two-phase systems (ATPSs) and complex coacervates are phase separation phenomena that lead to the selective partitioning of biomolecules and have recently been proposed as membrane-free protocell models. We show in this study through fluorescence recovery after photobleaching (FRAP) microscopy that despite the ability of such systems to effectively concentrate RNA, there is a high rate of RNA exchange between phases in dextran/polyethylene glycol ATPS and ATP/poly-L-lysine coacervate droplets. In contrast to fatty acid vesicles, these systems would not allow effective segregation and consequent evolution of RNA, thus rendering these systems ineffective as model protocells.
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Affiliation(s)
- Tony Z. Jia
- Howard Hughes Medical Institute, Department of Molecular Biology, and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114 USA
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, MA 02138 USA
| | - Christian Hentrich
- Howard Hughes Medical Institute, Department of Molecular Biology, and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114 USA
| | - Jack W. Szostak
- Howard Hughes Medical Institute, Department of Molecular Biology, and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street, Boston, MA 02114 USA
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, MA 02138 USA
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17
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Quirk S. Enhanced catalytic activity from proteinoid microspheres. J Biomed Mater Res A 2012; 101:1133-43. [PMID: 23023829 DOI: 10.1002/jbm.a.34421] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Accepted: 08/16/2012] [Indexed: 12/14/2022]
Abstract
Creating materials that are capable of catalyzing enzymatic reactions could be important to the treatment of both acute and chronic wounds, as well as other topical diseases. As a first step in the design of catalytic biomaterials, a new class of proteinoid microsphere (PM), that includes amino acids found in phosphatase enzyme active sites, has been constructed. This material can significantly enhance catalytic activity for phosphoester hydrolysis, with observed specific activity increases between 35- and 55-fold. Further specific activity increases occur when metal cations, notably iron or zinc, are added to the PMs. Specific activity increases between 140- and 300-fold for these metal modified systems are measured. The phosphatase activity increase is demonstrated for both aromatic phosphate esters as well as the high-energy phosphate bond of adenosine triphosphate. PMs bind substrate heterogeneously on their surfaces in an enthalpically driven reaction that is defined by an overall favorable free energy, but unfavorable entropy. The catalytic PMs have been successfully blended with polyolefin foam and extruded with PLA. These materials remain fully active.
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18
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Koga S, Williams DS, Perriman AW, Mann S. Peptide-nucleotide microdroplets as a step towards a membrane-free protocell model. Nat Chem 2011; 3:720-4. [PMID: 21860462 DOI: 10.1038/nchem.1110] [Citation(s) in RCA: 409] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2011] [Accepted: 07/05/2011] [Indexed: 11/09/2022]
Abstract
Although phospholipid bilayers are ubiquitous in modern cells, their impermeability, lack of dynamic properties, and synthetic complexity are difficult to reconcile with plausible pathways of proto-metabolism, growth and division. Here, we present an alternative membrane-free model, which demonstrates that low-molecular-weight mononucleotides and simple cationic peptides spontaneously accumulate in water into microdroplets that are stable to changes in temperature and salt concentration, undergo pH-induced cycles of growth and decay, and promote α-helical peptide secondary structure. Moreover, the microdroplets selectively sequester porphyrins, inorganic nanoparticles and enzymes to generate supramolecular stacked arrays of light-harvesting molecules, nanoparticle-mediated oxidase activity, and enhanced rates of glucose phosphorylation, respectively. Taken together, our results suggest that peptide-nucleotide microdroplets can be considered as a new type of protocell model that could be used to develop novel bioreactors, primitive artificial cells and plausible pathways to prebiotic organization before the emergence of lipid-based compartmentalization on the early Earth.
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Affiliation(s)
- Shogo Koga
- Centre for Organized Matter Chemistry, School of Chemistry, University of Bristol, Bristol BS8 1TS, UK
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19
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Abstract
Proteinoid microspheres (PM) are unusual polymers formed by the thermal condensation of amino acids. Although they have been studied for over 60 years, they are only now beginning to garner interest as controlled release agents. Although they are very biocompatible, it has been problematic to design useful triggers that release small molecules from PM interiors. This has severely limited their usefulness. In the present study, short peptides have been successfully incorporated into PMs during their formation. The resulting hybrid peptide-PMs can release their interior content when hydrolyzed by a proteinase. Specifically, if a matrix metalloproteinase (MMP) cleavage site peptide is incorporated into a PM, the peptide-PM will release interior contents only in the presence of the MMP recognizing the cleavage peptide. The release rate can be determined by the concentration of the peptide in the PM synthesis mixture. This potentially makes peptide-PMs useful for delivering inhibitors or drugs into acute and chronic wounds, periodontal disease sites, and other disease states involving the fine-tuned regulation of proteinases.
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Affiliation(s)
- Stephen Quirk
- Kimberly-Clark Corporation, Roswell, Georgia 30076, USA.
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20
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Quirk S. Triggered release of small molecules from proteinoid microspheres. J Biomed Mater Res A 2010; 91:391-9. [PMID: 18980224 DOI: 10.1002/jbm.a.32241] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Proteinoid microspheres (PM) are formed by the thermal condensation of amino acids. They have been useful to further evolutionary theory, as catalysts for some biochemical reactions, but they have not been overly useful as controlled delivery agents. It is possible however to construct PMs that contain organic small molecules in the interior space. This means that a PM could be used as a delivery agent, if a suitable method could be discovered to cause the release of the internal material. This report describes the formation of a PM that includes a molecular bridging agent that can be removed in a reducing environment. Removal of the bridge opens a hole or window in the PM that allows the interior material to escape. The rate at which the interior material is released from the PM can be controlled by the size of the window or by the reduction potential in the environment. These PMs can be used to temporally treat a variety of complications including wounds (chronic or acute) by delivering a sequestered reagent in a controlled manner and are advantageous in that amino acids are the primary delivery vehicle breakdown product.
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Affiliation(s)
- Stephen Quirk
- Kimberly-Clark Corp, 1400 Holcomb Bridge Rd., Roswell, GA 30076, USA.
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21
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Abstract
The proteinoid cells are assembled of thermal polymers of amino acids. Typically, an appropriate mixture of amino acids containing aspartic or glutamic acid is heated at 190 degrees C for 6 h, stirred with water for 2 h, dialyzed during 2 d, and lyophilized. Spheroidal cells are made from such polymer by dissolving it in the water by boiling, and then cooling. Many of them can be made by sonication at room temperature. These artificial cells, ranging from microns to tens of microns in diameter (depending on composition and preparation), have double membranes and various internal compositions. The spherules can microencapsulate dyes, oxidant-reductant compounds or acceptor-donor substances, and can be packed together. Such spherules display electrical polarization and electrical discharges and respond to intra- and extracellular ionic and electric influence upon membrane and action potential. These properties arise from the double membrane structure, asymmetric membrane permeability, and channeling phenomena. Such features as exponential dependence of the steady-state conductance and capacitance as well as negative resistance of the membrane seem to be responsible for the flip-flop alternations of the membrane polarization, rhythmic electric oscillations, and all-or-none action potentials. The presence of such chromophores as pteridine and flavin in polymers constituting these cells is responsible for their photosensitivity.
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Affiliation(s)
- A T Przybylski
- Institute for Molecular and Cellular Evolution, University of Miami, Coral Gables, FL 33134, USA
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22
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Abstract
The continuity of abiotically formed bilayer membranes with similar structures in contemporary cellular life, and the requirement for microenvironments in which large and small molecules could be compartmentalized, support the idea that amphiphilic boundary structures contributed to the emergence of life. As an extension of this notion, we propose here a 'Lipid World' scenario as an early evolutionary step in the emergence of cellular life on Earth. This concept combines the potential chemical activities of lipids and other amphiphiles, with their capacity to undergo spontaneous self-organization into supramolecular structures such as micelles and bilayers. In particular, the documented chemical rate enhancements within lipid assemblies suggest that energy-dependent synthetic reactions could lead to the growth and increased abundance of certain amphiphilic assemblies. We further propose that selective processes might act on such assemblies, as suggested by our computer simulations of mutual catalysis among amphiphiles. As demonstrated also by other researchers, such mutual catalysis within random molecular assemblies could have led to a primordial homeostatic system displaying rudimentary life-like properties. Taken together, these concepts provide a theoretical framework, and suggest experimental tests for a Lipid World model for the origin of life.
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Affiliation(s)
- D Segré
- Dept. of Molecular Genetics, Crown Human Genome Center, Weizmann Institute of Science, Rehovot 76100, Israel
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23
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Yanagawa H, Ogawa Y, Kojima K, Ito M. Construction of protocellular structures under simulated primitive earth conditions. ORIGINS LIFE EVOL B 1988; 18:179-207. [PMID: 3226717 DOI: 10.1007/bf01804670] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We have developed experimental approaches for the construction of protocellular structures under simulated primitive earth conditions and studied their formation and characteristics. Three types of envelopes; protein envelopes, lipid envelopes, and lipid-protein envelopes are considered as candidates for protocellular structures. Simple protein envelopes and lipid envelopes are presumed to have originated at an early stage of chemical evolution, interaction mutually and then evolved into more complex envelopes composed of both lipids and proteins. Three kinds of protein envelopes were constructed in situ from amino acids under simulated primitive earth conditions such as a fresh water tide pool, a warm sea, and a submarine hydrothermal vent. One protein envelope was formed from a mixture of amino acid amides at 80 degrees C using multiple hydration-dehydration cycles. Marigranules, protein envelope structures, were produced from mixtures of glycine and acidic, basic and aromatic amino acids at 105 degrees C in a modified sea medium enriched with essential transition elements. Thermostable microspheres were also formed from a mixture of glycine, alanine, valine, and aspartic acid at 250 degrees C and above. The microspheres did not form at lower temperatures and consist of silicates and peptide-like polymers containing imide bonds and amino acid residues enriched in valine. Amphiphilic proteins with molecular weights of 2000 were necessary for the formation of the protein envelopes. Stable lipid envelopes were formed from different dialkyl phospholipids and fatty acids. Large, stable, lipid-protein envelopes were formed from egg lecithin and the solubilized marigranules. Polycations such as polylysine and polyhistidine, or basic proteins such as lysozyme and cytochrome c also stabilized lipid-protein envelopes.
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Affiliation(s)
- H Yanagawa
- Mitsubishi-Kasei Institute of Life Sciences, Tokyo, Japan
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24
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Raulin F, Cerceau F, Hakdaoui M, Vargas A. Prebiotic chemical evolution in Titan’s ocean. ORIGINS LIFE EVOL B 1986. [DOI: 10.1007/bf02422097] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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25
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Architecture of models for protocellular structures formation of protein, lipid and lipid-protein vesicles. ORIGINS LIFE EVOL B 1986. [DOI: 10.1007/bf02422077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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26
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Yanagawa H, Nishizawa M, Kojima K. A possible prebiotic peptide formation from glycinamide and related compounds. ORIGINS OF LIFE 1984; 14:267-72. [PMID: 6462670 DOI: 10.1007/bf00933667] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
We examined an experimental approach to the genesis of protocells in the primeval sea. Glycine polymers with an average chain length of 12 were formed from glycinamide in fluctuating systems (pH 7.2, 80 degrees C, 20 cycles). The resulting glycine polymers gave aggregated leaflet-like structures. A solution of the glycine polymers provided stacked disc-shaped structures in the presence of LiBr and gave sheet structures in the presence of dichloroacetic acid. The shapes of these organized structures were correlated with their molecular structures.
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27
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28
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Abstract
Material self-assembly as exemplified in protobiogeneses is shown to be result of molecular exchange interaction in reacting chemicals. Temporally and spatially correlated aggregates of reacting chemicals work as vertices of molecular exchange interaction. If the material accumulation rate at a locally correlated aggregate spontaneously happens to become positive at a certain time, the material accumulation due to self-assembly will increase with time afterward. A spontaneous formation of looped reaction at locally correlated aggregates of reacting chemicals can initiate a material self-assembly at succeeding times.
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29
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Abstract
The appearance of reproducing microsystems during stimulated protobiogenesis is investigated theoretically, based upon the observation that proteinoid microsystems, which are local aggregates of reacting chemicals, act as reaction nodes. Further splitting of such nodes follows if sufficient growth takes place. Parent-connected daughter nodes thus appear. A parent-connected daughter node rejuvenates itself while its parent node survives, although an extinction of the latter is inevitable in the presence of spontaneous disturbances. The degree of rejuvenation is measured in terms of the molecule intake and dissociation rates at the node. A daughter node grows and matures after the extinction of its parent, and gives rise to second-generation nodes when it grows sufficiently large. The parent node alternates with its parent-connected daughter nodes successively.
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30
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Nakashima T, Fox SW. Formation of peptides from amino acids by single or multiple additions of ATP to suspensions of nucleoproteinoid microparticles. Biosystems 1981; 14:151-61. [PMID: 6794660 DOI: 10.1016/0303-2647(81)90064-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
When lysine-rich proteinoid, which catalyzes the formation of peptides from amino acids and ATP, is complexed with acidic proteinoid to form microspheres of mixed constitution, the normal synthesis by basic proteinoid alone is multiplied several-fold. The product consists not only of small peptides but also of a high-molecular-weight fraction of substituted proteinoid. Suspensions of particles of lysine-rich proteinoid complexed with polyadenylic acid catalyze the synthesis of peptides from each of the amino acids tested with ATP. When equimolar solutions of mixtures of glycine and phenylalanine with ATP are tested in suspensions of complexes of lysine-rich proteinoid and each of various polyribonucleotides, both homopeptides and heteropeptides are produced. Glycylphenylalanine or phenylalanylglycine is the principal product; the preference is related to which polyribonucleotide is in the complex. The rate of conversion of amino acid to peptide is a function of whether ATP is added in a single batch or in repeated amounts adding to the same amount as in the single batch. Related experiments indicate a relatively rapid initial rate of decay of ATP in the system. These results are discussed relative to the mechanisms for continuous generation in modern organisms, as are the results in peptide formation.
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31
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Matsuno K. Compartmentalization of self-reproducing machineries: multiplication of microsystems with self-instructing polymerization of amino acids. ORIGINS OF LIFE 1980; 10:361-70. [PMID: 7454257 DOI: 10.1007/bf00928309] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A theoretical model is presented for the self-instructing polymerization of free amino acids which proceeds inside microsystems which are phase-separated from the solution of thermal polyamino acids. It is shown theoretically that a compartmentalized microsystem fixes inside itself only the process with a faster macromolecular multiplication as time passes, even if the catalytic polymerization alone could spontaneously decrease the corresponding reaction rate. The compartmentalized machinery of macromolecular multiplication cannot reach its stationary state. The machinery is inevitably multiplied and alternates with those with either faster rates of macromolecular multiplication or slower rates of macromolecular degradation during their time development. These results are based upon the dynamic process that any material system acts by itself so as to remove any flow disequilibrium, that is, to maintain the continuity of material flow.
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32
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Matsuno K. Operational description of microsystems formation in prebiological molecular evolution. ORIGINS OF LIFE 1980; 10:39-45. [PMID: 7366954 DOI: 10.1007/bf00928942] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A theoretical analogue of microsystems formation in prebiological molecular evolution, known, for instance, as microspheres of Fox and marigranules of Yanagawa and Egami, is presented for a model solution system of polyamino acids in which the polymerization due to peptide bond synthesis is initially not in a complete balance with the hydrolysis. The homogeneous solution of polyamino acids, which is in a nonequilibrium state in the sense that a complete balance among all the participating reactions has not yet been established, is unstable against forming microscopic compartments of locally condensed peptide bond linkages. It also follows that both the accumulation of polyamino acids and the number of peptide bond linkages inside the localized microsystems increase with time so long as the solution remains in a nonequilibrium state lacking the balance between the polymerization and the hydrolysis. The phase separation of microsystems from the homogeneous solution of polyamino acids is just a representation of the unidirectional dynamic process that any reaction system, which initially lacks a complete balance among all the participating reactions, evolves toward a goal, if any, at which an equilibrium balancing of reactions be finally established.
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33
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Fox SW. Organic microstructures and terrestrial protocells. THE SCIENCE OF NATURE - NATURWISSENSCHAFTEN 1977; 64:380-1. [PMID: 927541 DOI: 10.1007/bf00368740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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34
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YANAGAWA H, EGAMI F. Formation of Protocell-like Structures from Glycine and Formaldehyde in a Modified Sea Medium. ACTA ACUST UNITED AC 1977. [DOI: 10.2183/pjab1945.53.42] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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