Molecular Ratchets and Kinetic Asymmetry: Giving Chemistry Direction

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(23)

Published: April 3, 2024

Abstract Over the last two decades ratchet mechanisms have transformed understanding and design of stochastic molecular systems—biological, chemical physical—in a move away from mechanical macroscopic analogies that dominated thinking regarding dynamics in 1990s early 2000s (e.g. pistons, springs, etc), to more scale‐relevant concepts underpin out‐of‐equilibrium research sciences today. Ratcheting has established nanotechnology as frontier for energy transduction metabolism, enabled reverse engineering biomolecular machinery, delivering insights into how molecules ‘walk’ track‐based synthesisers operate, acceleration reactions enables be transduced by catalysts (both motor proteins synthetic catalysts), dynamic systems can driven equilibrium through catalysis. The recognition biology, their invention systems, is proving significant areas diverse supramolecular chemistry, covalent DNA nanotechnology, polymer materials science, heterogeneous catalysis, endergonic synthesis, origin life, many other branches science. Put simply, give chemistry direction. Kinetic asymmetry, key feature ratcheting, counterpart structural asymmetry (i.e. chirality). Given ubiquity processes significance behaviour function it surely just fundamentally important. This Review charts recognition, development ratchets, focussing particularly on role which they were originally envisaged elements machinery. Different kinetically asymmetric are compared, consequences discussed. These archetypal examples demonstrate inexorably equilibrium, rather than relax towards it.

Language: Английский

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Transducing chemical energy through catalysis by an artificial molecular motor

Nature, Journal Year: 2025, Volume and Issue: 637(8046), P. 594 - 600

Published: Jan. 15, 2025

Abstract Cells display a range of mechanical activities generated by motor proteins powered through catalysis 1 . This raises the fundamental question how acceleration chemical reaction can enable energy released from that to be transduced (and, consequently, work done) molecular catalyst 2–7 Here we demonstrate molecular-level transduction force 8 in form contraction and re-expansion cross-linked polymer gel driven directional rotation artificial catalysis-driven 9 motors. Continuous 360° rotor about stator motor-molecules incorporated polymeric framework twists chains network around one another. progressively increases writhe tightens entanglements, causing macroscopic approximately 70% its original volume. The subsequent addition opposite enantiomer fuelling system powers reverse direction, unwinding entanglements re-expand. Continued twisting strands new direction causes re-contract. In actuation, motor-molecule produces other physical outcomes, including changes Young modulus storage modulus—the latter is proportional increase strand crossings resulting rotation. experimental demonstration against load synthetic organocatalyst, mechanism 6 , informs both debate 3,5,7 surrounding generation biological motors design principles 6,10–14 for nanotechnology.

Language: Английский

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Photoswitchable Imines Drive Dynamic Covalent Systems to Nonequilibrium Steady States

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(30), P. 20720 - 20727

Published: July 18, 2024

Coupling a photochemical reaction to thermal exchange process can drive the latter nonequilibrium steady state (NESS) under photoirradiation. Typically, systems use separate motifs for photoresponse and equilibrium-related processes. Here, we show that photoswitchable imines fulfill both roles simultaneously, autonomously driving dynamic covalent system into NESS continuous light irradiation. We demonstrate this using transimination reactions, where

Language: Английский

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Structural Influence of the Chemical Fueling System on a Catalysis-Driven Rotary Molecular Motor

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 27, 2025

Continuous directionally biased 360° rotation about a covalent single bond was recently realized in the form of chemically fueled 1-phenylpyrrole 2,2′-dicarboxylic acid rotary molecular motor. However, original fueling system and reaction conditions resulted motor directionality only ∼3:1 (i.e., on average backward for every three forward rotations), along with catalytic efficiency operation 97% fuel 14%. Here, we report efficacy series chiral carbodiimide fuels hydrolysis promoters (pyridine pyridine N-oxide derivatives) driving improved directional this motor-molecule. We outline complete network operation, composed directional, futile, slip cycles. Using derivatives where final conformational step is either very slow or completely blocked, phenylpyrrole diacid becomes enantiomerically enriched, allowing kinetic gating individual steps cycle to be measured. The that produces highest gives 13% enantiomeric excess (e.e.) anhydride-forming kinetically gated step, while most effective promoter generates 90% e.e. step. Combining best-performing into results 92% e.e.. Under dilute chemostated regime (to avoid N-acyl urea formation at high concentrations promoters), continuously rotates ∼24:1 24 rotations) >99% 51%.

Language: Английский

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Artificial molecular pumps

Nature Reviews Methods Primers, Journal Year: 2024, Volume and Issue: 4(1)

Published: Feb. 22, 2024

Language: Английский

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Analysis of kinetic asymmetry in a multi-cycle reaction network establishes the principles for autonomous compartmentalized molecular ratchets

Chem, Journal Year: 2024, Volume and Issue: 10(12), P. 3644 - 3655

Published: Sept. 13, 2024

Language: Английский

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Analysis of kinetic asymmetry in a multi-cycle chemical reaction network establishes the principles for autonomous compartmentalized molecular ratchets

Published: Feb. 21, 2024

Kinetic asymmetry is a key parameter describing non-equilibrium chemical systems: it indicates the directionality of reaction network under steady-state, conditions. So far, kinetic has been evaluated only in networks featuring single cycle. Here, we have investigated multi-cycle system using combined theoretical and numerical approach. Inspired by latest experimental developments, selected com-partmentalized redox-controlled as model system. We report general analytical expression for networks, specify present system, which allows anticipating how parameters influence directionality. establish that compartmentalization can enable autonomous energy ratchet mechanisms, with dictated system's thermodynamics. simulations confirm findings illustrate interplay between diffusion, chemical, electrochemical processes. The presented treatment general, same procedure be used to assess other facilitating realization en-dergonic processes across domains.

Language: Английский

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Beyond Single‐Cycle Autonomous Molecular Machines: Light‐Powered Shuttling in a Multi‐Cycle Reaction Network

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 64(2)

Published: Aug. 17, 2024

Biomolecular machines autonomously convert energy into functions, driving systems away from thermodynamic equilibrium. This conversion is achieved by leveraging complex, kinetically asymmetric chemical reaction networks that are challenging to characterize precisely. In contrast, all known synthetic molecular in which kinetic asymmetry has been quantified well described simple single-cycle networks. Here, we report on a unique light-driven [2]rotaxane enables the autonomous operation of machine with multi-cycle network. Unlike prior systems, present one exploits photoactive macrocycle, features different photoreactivity depending binding sites at it resides. Furthermore, E Z isomerization reverses relative affinity macrocycle for two axle, resulting Building most recent theoretical advancements, this work quantifies network first time. Our findings represent simplest rotaxane capable shuttling developed so far and offer general strategy generate quantify beyond systems.

Language: Английский

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Organic Reactivity Matters for the Emergence of Life: Kinetic Barriers and Molecular Diversity Are Suggested as Crucial Factors by Emerging Autonomous System Models

ChemSystemsChem, Journal Year: 2025, Volume and Issue: unknown

Published: March 13, 2025

Abstract The idea that organic chemistry can gradually self‐organize towards the emergence of life has been challenged by views considering most important driver should be existence a crucial thermodynamic disequilibrium. In this work, past are critically addressed and mechanism through which disequilibrium promote development organized systems is suggested. This analysis based on propensity carbon to form covalent bonds with other elements, usually corresponds deep energy wells generating high kinetic barriers hindering reactions. Potential associated considered as storing prepaid entropy loss within potential surface therefore constitute giving room for subsequent self‐organization processes. notion Kinetically Stable Thermodynamically Activated (KSTA) compounds gives rise possibility alternative pathways non‐linear autocatalytic As working in far‐from‐equilibrium context, like molecular machines, parameters determining how they proceed change, suggests interactions between fields machines could mutually beneficial.

Language: Английский

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From Brownian to Deterministic Motor Movement in a DNA-Based Molecular Rotor

Nano Letters, Journal Year: 2024, Volume and Issue: 24(17), P. 5224 - 5230

Published: April 19, 2024

Molecular devices that have an anisotropic periodic potential landscape can be operated as Brownian motors. When the is cyclically switched with external force, such harness random fluctuations to generate a directed motion. Recently, motor-like rotatory movement was demonstrated electrically DNA origami rotor designed ratchet-like obstacles. Here, we demonstrate intrinsic anisotropy of rotors also sufficient result in motor movement. We show for low amplitudes switching field, operate motors, while at higher amplitudes, they behave deterministically overdamped electrical characterize amplitude and frequency dependence movements, showing after initial steep rise, angular speed peaks drops excessive driving frequencies. The well described by simple stochastic model system.

Language: Английский

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