ChemSystemsChem最新文献

Phosphorus (P) is a limiting element for prebiotic/biotic activity, and its availability constrains planetary habitability. Phosphates detected in Enceladus’ plume material could expand the range of potential prebiotic reactions possibly occurring within its subsurface ocean. However, for phosphorus chemistry to influence potential prebiotic chemistry, the environment must be favorable for the production of organophosphates and condensed phosphorus species. While mechanisms for the formation of organophosphates and polyphosphates exist within an early Earth context, these reactions rely on various environmental sources of phosphorus and are typically dependent on a low water activity environment to drive condensation or phosphorylation. For Enceladus, this would limit such reactions to within the core and/or hydrothermal systems, and water-rock chemistry in Enceladus’ core would be the singular source for oceanic phosphorus for prebiotic chemistry. Here we discuss the production of organophosphates, reduced P compounds, and polyphosphates that might be possible within Enceladus, based on our understanding of prebiotic phosphorus reactions on early Earth.

Random molecular fluctuations, or stochasticity, are intrinsic to all biological systems, influencing processes from molecular interactions to cellular biochemistry. These fluctuations, often labelled as “noise,” are not always disruptive but can serve as a source of adaptability and functionality. Evolution has taken place in the presence of these molecular fluctuations over billions of years, yielding mechanisms that enable versatile and enhanced activity of a range of biochemical processes. This review explores how stochastic variations, from Brownian motion to higher-order system dynamics, can drive complex biological functions. First, we summarize landmark examples of the role of stochasticity in biological processes, emphasizing its capacity to yield beneficial outcomes. Computational modeling and model experimental systems are highlighted as tools to investigate stochasticity in a quantitative manner. In addition, the review comments on how deliberate incorporation of stochasticity into synthetic experimental systems provides novel avenues for controlling and designing life-like processes. By understanding and utilizing stochastic variation, new principles for engineering robust and adaptable synthetic systems are uncovered.

Designing synthetic chemical systems capable of mimicking life-like behavior surely will help to understand the basic principles sustaining life, but also to create advanced materials potentially going beyond nature. Herein, we report the synthesis of a family of lipoamino acids from their individual components, which are free amino acids and lipid precursors, that allow us to study competition and selection in their formation. Octanoyl-L-histidine outcompetes from a pool of natural amino acids and a family of lipids, emerging as the fittest, where the observed selectivity is the result of a very efficient autocatalytic mechanism.

Homotypic coacervates, formed of a single component, are notable for compartmentalization and could serve as artificial cells for our understanding of living cells. Recently, small designer biomolecules have been investigated for liquid–liquid phase separation (LLPS), like intrinsically disordered proteins (IDPs), allowing them to make coacervate droplets spontaneously through associative molecular interactions. In this context, we highlight the recent developments in the reductionist approach for designer biomolecules, particularly amino acid derivatives, dipeptides, and bioinspired polypeptides, which undergo coacervation to create biomimetic protocells. Weak non-covalent molecular interactions usually drive the self-coacervation of biomolecules, and their structure-function properties are crucial for phase separation. Besides this, we discuss the essential parameters required for promising applications of protocell formation to mimic living cells, including the catalytic ability for enzymatic reactions and the sequestration of micro- and macro-molecules. Finally, we provide some perspective and conclude that simple coacervates formed from small peptide building blocks undergo phase separation to form protocells.

The experimental study of reaction–diffusion-driven chemical and biological systems is a key to understanding pattern formation in nature. Starting from experiments performed in a Petri dish or test tube, various reactors have been designed to explore the dynamics of fronts, waves, and stationary patterns. We focus on the cases where the underlying instabilities are driven by kinetics and diffusion, and the presence of fluid motion is avoided or plays a minor role. This review discusses the most commonly used reactor configurations, their intended purposes, and the associated drawbacks. The typical patterns observed in the different reactors are also exemplified. We highlight how the properties of the targeted patterns and the reaction networks influence the selection of the reactor design to be applied. The main characteristics of the reactors are the operation mode (batch or continuous), the type of medium in which the reaction–diffusion (RD) phenomenon develops, and the method of reactant supply (mixed or separated). Besides understanding the fundamental aspects of pattern formation, these reactors open a way to perform non-equilibrium synthesis and nonconventional computation, which is crucial in supramolecular chemistry.

Dissipative (non-equilibrium) chemical systems whose properties are transitorily changed by light or chemical stimuli are increasingly investigated. Among chemical stimuli, activated carboxylic acids (ACAs) are used to drive acid–base-based dissipative systems. Here, we give a comprehensive description of the operation mechanisms of such systems. Three types of systems are identified: systems under dissipative conditions (Type 1), energy ratchets (Type 2), and non-equilibrium steady state (NESS) systems (Type 3). Type 1 systems are driven from an equilibrium state to another via protonation by the ACA. However, this new equilibrium is transient because decarboxylation of the ACA conjugate base and back proton transfer rapidly restore the initial state. In Type 2 systems, after ACA consumption, the system is brought into an out-of-equilibrium state. Consequently, part of the free energy change due to the ACA decarboxylation is transferred to the system. Differently from Types 1 and 2, in Type 3 systems, ACA decarboxylation is part of the cyclic network; when fuel and waste species are chemostatted, a NESS can be reached displaying kinetic asymmetry.

There is an active interest in living matter from a systemic perspective. Whereas the targeted goal of producing living matter remains elusive, it may currently be useful to recognize some steps along the way and underline their intrinsic value, independently of the final goal. Hence, conceived to support further research in the field, this account evokes several preliminary developments which have only been partially performed, methodologies that could be engaged, and difficulties that are worth considering for optimal design of the future experimental plans.

Micrometer-sized liposomes (MSLs) are gaining attention as platforms for applications ranging from biophysical cell models to molecular robots. However, comprehensive cross-disciplinary reviews remain scarce. The review by Shogo Hamada, Taro Toyota, and co-workers addresses this gap by systematically covering MSL design, including applications, functionalization, and formation, serving as a guide for researchers and newcomers seeking to explore their broad potential across various disciplines.

Lipid membranes are important components of all living organisms. Giant unilamellar vesicles (GUVs) with diameters ranging from several to a few hundred micrometers provide a unique opportunity to study physical chemistry of biomembranes.In this paper, the response behaviors of GUVs under acoustic radiation force is investigated. The temperature-mediated deformation of GUVs and GUVs deformation with binary lipid composition under acoustic field were studied in detail. We believe that the deformation behavior of GUVs under acoustic radiation force will provide a new platform for membrane mechanical properties research and can be used in biotechnology.

Over the past decade there has been a tremendous development of systems capable to autonomously convert energy, in particular light and chemical, into directed motion at the nanoscale. These nanoscopic devices are called molecular motors. The autonomous operation of artificial molecular motors and pumps under constant experimental conditions represents a key achievement to their implementation into more sophisticated networks. Nonetheless, the principles behind successful autonomous operation are only recently being rationalized. Within this review we focus on the fundamental aspects that enable the autonomous operation of molecular motors exploiting light and chemical energy. We also compare the mechanisms of operation with these two energy sources and highlight the common ground of these systems as well as their differences and specificities by discussing a selection of recent examples in the two classes. Finally, we provide a perspective view on future advances in this exciting research area.