Protocell Dynamics: Modelling Growth and Division of Lipid Vesicles Driven by an Autocatalytic Reaction

Life, Journal Year: 2025, Volume and Issue: 15(5), P. 724 - 724

Published: April 29, 2025

We study a computational model of protocell, in which an autocatalytic reaction sustains itself inside lipid vesicle. The drives volume growth via osmosis. Membrane area grows due to addition lipids from the environment. membrane rate depends on external concentration and tension membrane. In absence division, cell either reaches state homeostasis or point where internal collapses. If becomes elongated, it can divide into two smaller spherical vesicles, conserving total area. determine when is energetically favorable for large vesicle divide. Division requires buildup difference between areas outer inner leaflets occurs most easily flipping relatively slow. too fast, parent without dividing. There typical size at division occurs, producing daughter cells unequal sizes. larger daughters regrow same before next division. Protocells with active metabolism reach stable are well balanced. Active protocells grow conditions inactive cannot.

Language: Английский

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Nonequilibrium Membrane Dynamics Induced by Active Protein Interactions and Chemical Reactions: A Review

ChemSystemsChem, Journal Year: 2024, Volume and Issue: unknown

Published: July 22, 2024

Abstract Biomembranes wrapping cells and organelles are not only the partitions that separate insides but also dynamic fields for biological functions accompanied by membrane shape changes. In this review, we discuss spatiotemporal patterns fluctuations of membranes under nonequilibrium conditions. particular, focus on theoretical analyses simulations. Protein active forces enhance or suppress fluctuations; height spectra deviated from thermal spectra. binding unbinding to is activated inhibited other proteins chemical reactions, such as ATP hydrolysis. Such processes can induce traveling waves, Turing patterns, morphological They be represented continuum reaction‐diffusion equations discrete lattice/particle models with state flips. The effects structural changes in amphiphilic molecules molecular‐assembly structures discussed.

Language: Английский

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Ferric hemebin aqueous micellar and vesicular systems: state-of-the-art and challenges

Quarterly Reviews of Biophysics, Journal Year: 2023, Volume and Issue: 56

Published: Jan. 1, 2023

Abstract Ferric heme b (= ferric protoporphyrin IX = hemin) is an important prosthetic group of different types enzymes, including the intensively investigated and widely applied horseradish peroxidase (HRP). In HRP, hemin present in monomeric form a hydrophobic pocket containing among other amino acid side chains two imidazoyl groups His170 His42. Both acids are for activity HRP as axial ligand (proximal His170) acid/base catalyst (distal His42). A key feature mechanism initial formation compound I under heterolytic cleavage added hydrogen peroxide terminal oxidant. Investigations free dispersed aqueous solution showed that dimers can form, depending on experimental conditions, possibly resulting crystallization. Although it has been recognized already 1970s aggregation be prevented by using micelle-forming amphiphiles, remains challenge to prepare hemin-containing micellar vesicular systems with peroxidase-like activities. Such interest cheap HRP-mimicking catalysts analytical synthetic applications. Some concepts which research this fascinating interdisciplinary field based summarized, along major accomplishments possible directions further improvement. systematic analysis physico-chemical properties solutions dispersions must combined reliable evaluation its catalytic activity. Future studies should show how well molecular complexity around mimicked micelles or vesicles. Because importance virtually all biological fact porphyrins hemes obtained potentially prebiotic ideas exist about role heme-containing times.

Language: Английский

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Hybrid Protocells based on Coacervate-Templated Fatty Acid Vesicles combine Improved Membrane Stability with Functional Interior Protocytoplasm

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Aug. 8, 2024

Abstract Prebiotically-plausible compartmentalization mechanisms include membrane vesicles formed by amphiphile self-assembly and coacervate droplets liquid-liquid phase separation. Both types of structures form spontaneously can be related to cellular motifs in today’s living cells. As prebiotic compartments, they have complementary capabilities, with coacervates offering excellent solute accumulation membranes providing superior boundaries. Herein, we describe protocell models constructed spontaneous encapsulation mixed fatty acid/phospholipid purely acid membranes. Coacervate-supported over a range lipid compositions, properties impacted charge-charge interactions between Vesicles coacervate-templated assembly exhibited profoundly different permeability than traditional or blended without interiors, particularly the presence Mg 2+ ions. While were disrupted addition 25 mM MgCl 2 , corresponding coacervate-supported remained intact impermeable externally-added solutes even . With more robust membrane, fluorescein diacetate (FDA) hydrolysis, which is commonly used for cell viability assays, could performed inside model due simple diffusion FDA then following coacervate-mediated abiotic hydrolysis fluorescein.

Language: Английский

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Optimization and Enhancement of the Peroxidase-like Activity of Hemin in Aqueous Solutions of Sodium Dodecylsulfate

ACS Omega, Journal Year: 2023, Volume and Issue: 8(45), P. 42878 - 42899

Published: Nov. 3, 2023

Iron porphyrins play several important roles in present-day living systems and probably already existed very early life forms. Hemin (= ferric protoporphyrin IX = heme b), for example, is the prosthetic group at active site of peroxidases, catalyzing oxidation a number different types reducing substrates after hemin first oxidized by hydrogen peroxide as oxidizing substrate enzyme. The peroxidases consists hydrophobic pocket which embedded noncovalently kept place through coordination iron atom to proximal histidine side chain protein. It this partially local environment enzyme determines efficiency with sequential reactions proceed site. Free hemin, has been separated from protein moiety known aggregate an aqueous solution exhibits low catalytic activity. Based on previous reports use surfactant micelles solubilize free nonaggregated state, peroxidase-like activity presence sodium dodecyl sulfate (SDS) concentrations below above critical concentration SDS micelle formation (critical micellization (cmc)) was systematically investigated. In most experiments, 3,3′,5,5′-tetramethylbenzidine (TMB) applied pH 7.2. clearly had positive effect reaction terms initial rate yield, even cmc. highest correlated cmc value, demonstrated three HEPES concentrations. 4-(2-hydroxyethyl)-1-piperazineethanesulfonate salt (HEPES) served buffer substance also accelerating reaction. At cmc, addition l-histidine (l-His) resulted further concentration-dependent increase until maximal reached optimal l-His concentration, corresponding ideal mono-l-His ligation hemin. Some results obtained can be understood basis molecular dynamics simulations, indicated existence intermolecular interactions between SDS. Preliminary experiments SDS/dodecanol vesicles 7.2 showed that vesicles, exhibited similar case micelles. This supports hypothesis micelle- or vesicle-associated ferrous may have played role primitive catalysts membranous prebiotic compartment before cellular emerged.

Language: Английский

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Interactions of Clay Minerals with Biomolecules and Protocells Complex Structures in the Origin of Life: A Review

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: July 21, 2024

Abstract The origin of life (OoL) has always been a mysterious and challenging topic that puzzles human beings. Clay minerals have unique properties wide distribution in early Earth environments. They can not only adsorb biological small molecules to catalyze their polymerization, but play an active role the formation evolution protocells. In this review, research progress on interactions clay with biomolecules protocells complex structures field OoL based chemical theory is summarized. types, minerals, protocell models related are introduced detail. mechanism interaction between molecules, construction formation, structure stability systematically described. Finally, future priorities challenges discussed. It aspired review further advance exploration from new perspective, also bring some interesting findings ideas interdisciplinary materials, biology, chemistry other disciplines.Clay variety biomolecules, which be used as structural functional templates promote organic synthesis protocells, playing non‐negligible OoL.

Language: Английский

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Light-Switchable Membrane Permeability in Giant Unilamellar Vesicles

Pharmaceutics, Journal Year: 2022, Volume and Issue: 14(12), P. 2777 - 2777

Published: Dec. 12, 2022

In this work, giant unilamellar vesicles (GUVs) were synthesized by blending the natural phospholipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) with a photoswitchable amphiphile (1) that undergoes photoisomerization upon irradiation UV-A (E to Z) and blue (Z E) light. The mixed showed marked changes in behavior response UV light, including morphology opening of pores. fine control membrane permeability consequent cargo release could be attained modulating either intensity or composition. As proof concept, photocontrolled sucrose from GUVs is demonstrated using microscopy (phase contrast) confocal studies. increased ~4 × 10-2 μm/s when system was illuminated With respect previously reported systems (entirely composed synthetic amphiphiles), our findings demonstrate potential photosensitive are mainly lipids used medical biomedical applications, such as targeted drug delivery localized topical treatments.

Language: Английский

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Proto–Neurons from Abiotic Polypeptides

Published: Nov. 1, 2023

Understanding the origins of life involves dealing with unresolved question how first informational polymers and cell-like structures emerged from prebiotic chemistry. The formation thermal proteinoids through heating mixtures amino acids, leading to spontaneous protocells enclosed by membranes, presents a compelling model for synthesis polypeptides in an abiogenic context. Recent research has revealed presence electrical excitability signal processing capacities proteinoids, indicating possibility primitive cognitive functions problem-solving capabilities. present study provides comprehensive examination features shown heat their potential significance context artificial during early stages Earth’s development. Experiments showcasing unconventional computing as well modelling proteinoid assemblies into synthetic proto-brains are given. Proteinoids’ robust production, biomimetic features, computational capability shed light on phases evolution primordial environment.

Language: Английский

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Concepts of a synthetic minimal cell: Information molecules, metabolic pathways, and vesicle reproduction

Biophysics and Physicobiology, Journal Year: 2023, Volume and Issue: 21(1), P. n/a - n/a

Published: Dec. 18, 2023

How do the living systems emerge from non-living molecular assemblies? What physical and chemical principles supported process? To address these questions, a promising strategy is to artificially reconstruct cells in bottom-up way. Recently, authors developed "synthetic minimal cell" system showing recursive growth division cycles, where concepts of information molecules, metabolic pathways, cell reproduction were concisely redesigned with vesicle-based system. We intentionally avoided using sophisticated machinery biological tried redesign simplest forms. This review focuses on similarities differences between our synthetic concerning each concept cells. Such comparisons natural artificial will provide insights how molecules should be assembled create wide readers field biology, cells, protocells research. article an extended version Japanese "Growth vesicles coupled molecules," published SEIBUTSU-BUTSURI vol. 61, p. 378-381 (2021).

Language: Английский

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Interface Binding Mechanism of Nanoclay Hybridized Coacervate Microdroplets for the Controllable Construction of Protocells

The Journal of Physical Chemistry Letters, Journal Year: 2024, Volume and Issue: 15(19), P. 5295 - 5305

Published: May 9, 2024

Coacervate microdroplets, a protocell model in exploring the origin of life, have gained significant attention. Clay minerals, catalysts during are crucial chemical evolution small molecules into biopolymers. However, our understanding relationship between clay minerals and formation protocells on early Earth remains limited. In this work, nanoclay montmorillonite nanosheet (MMT-Na) was employed to investigate its interaction with coacervate microdroplets formed by oligolysine (K10) adenine nucleoside triphosphate (ATP). As an anionic component, MMT-Na noted promote microdroplets. Furthermore, efficiency ssDNA enrichment degree hybridization within these were significantly improved. By combining inorganic organic biopolymers, work provides efficient way enrich genetic biomolecules primitive environment builds nanoclay-based shedding new light life's evolution.

Language: Английский

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