Proton Flow Research Articles

Long-Range Proton Channels Constructed via Hierarchical Peptide Self-Assembly.

The quest to understand and mimic proton translocation mechanisms in natural channels has driven the development of peptide-based artificial channels facilitating efficient proton transport across nanometric membranes. It is demonstrated here that hierarchical peptide self-assembly can form micrometers-long proton nanochannels. The fourfold symmetrical peptide design leverages intermolecular aromatic interactions to align self-assembled cyclic peptide nanotubes, creating hydrophilic nanochannels between them. Titratable amino acid sidechains are positioned adjacent to each other within the channels, enabling the formation of hydrogen-bonded chains upon hydration, and facilitating efficient proton transport. Moreover, these chains are enriched with protons and water molecules by interacting with immobile counter ions introduced into the channels, increasing proton flow density and rate. This system maintains proton transfer rates closely resembling those in natural protein channels over micrometer distances. The functional behavior of these inherently recyclable and biocompatible systems opens the door for their exploitation in diverse applications in energy storage and conversion, biomedicine, and bioelectronics.

Imaging Metabolic Flow of Water in Plants with Isotope-Traced Stimulated Raman Scattering Microscopy.

Water plays a vital role in the life cycle of plants, participating in various critical biochemical reactions during both non-photosynthetic and photosynthetic processes. Direct visualization of the metabolic activities of water in plants with high spatiotemporal resolution is essential to reveal the functional utilization of water. Here, stimulated Raman scattering (SRS) microscopy is applied to monitor the metabolic processes of deuterated water (D2O) in model plant Arabidopsis thaliana (A. thaliana). The work shows that in plants uptaking D2O/water solution, proton-transfer from water to organic metabolites results in the formation of C-D bonds in newly synthesized biomolecules (lipid, protein, and polysaccharides, etc.) that allow high-resolution detection with SRS. Reversible metabolic pathways of oil-starch conversion between seed germination and seed development processes are verified. Spatial heterogeneity of metabolic activities along the vertical axis of plants (root, stem, and tip meristem), as well as the radial distributions of secondary growth on the horizontal cross-sections are quantified. Furthermore, metabolic flow of protons from plants to animals is visualized in aphids feeding on A. thaliana. Collectively, SRS microscopy has potential to trace a broad range of matter flows in plants, such as carbon storage and nutrition metabolism.

High-Performance Proton Field-Effect Transistor Based on Two-Dimensional Cd Vacancy-Resided Cd0.85PS3Li0.15H0.15.

Ion transport is a critical phenomenon underpinning numerous biological, physical, and chemical systems. Proton transistors leveraging proton transport face significant limitations, such as a low on-off ratio and deficient carrier mobility, which restrict their applicability in biological and other scenarios. This study explores the use of two-dimensional (2D) vacancy-residing transition metal phosphorus trichallcogenide-based membranes as the active layer for proton field-effect transistors. The synthesized Cd0.85PS3Li0.15H0.15 membrane exhibits a well-organized layered structure and high hydrophilicity, with nanometer-sized interlayers containing interconnected water networks. These distinct features facilitate proton conduction, leading to a high proton conductivity value of 0.83 S cm-1 at 98% relative humidity and 90 °C, with an activation energy of 0.26 eV. The Cd0.85PS3Li0.15H0.15-based proton transistor demonstrates tunability via gate voltage, thereby enabling effective modulation of proton flow across source and drain electrodes. The transistor notably showcases superior switching characteristics, with an on/off ratio surpassing 5.51 and a carrier mobility of 8.84 × 10-2 cm2 V-1 s-1. The underlying mechanism for this performance enhancement is attributed to electric-field-induced switching in Cd vacancies. This research boosts the development of highly versatile ionotropic devices by introducing advanced 2D ion-conductive membranes.

Machine learning models for predicting geomagnetic storms across five solar cycles using Dst index and heliospheric variables

This study aims to improve the understanding of geomagnetic storms by utilizing machine learning models and analyzing several heliophysical variables, such as the interplanetary magnetic field, proton density, solar wind speed, and proton temperature. Rather than relying on traditional correlation-based methods, we employ advanced machine learning techniques to examine the complex relationships between these factors and geomagnetic storms. Our analysis covers a large dataset spanning six solar cycles, including the current 25th cycle, to provide comprehensive insights into the dynamics of these storms.Our study highlights the significance of the interplanetary magnetic field as a key predictor of geomagnetic storms, challenging previous beliefs that primarily focused on sunspot activity. By using high-resolution data, we uncover new patterns and provide a more detailed analysis of the factors influencing geomagnetic storms. We emphasize the importance of considering a range of heliophysical variables, such as proton temperature and flow pressure, which offer new insights into the complex dynamics driving these storm events.The application of machine learning models, particularly Random Forest and Gradient Boosting, demonstrated superior predictive accuracy compared to traditional methods. Our results reveal that the Dst-index MIN, scalar B, and alpha/proton ratio are among the most influential factors, accounting for a significant portion of the prediction model’s accuracy. These findings underscore the utility of machine learning in identifying critical drivers of geomagnetic activity and enhancing forecast precision.Additionally, our research underscores the need for comprehensive models that can accurately predict geomagnetic storms by integrating various data sources. This machine learning approach not only improves predictive accuracy but also enhances our understanding of the underlying mechanisms of space weather. The insights gained from this study have important implications for both scientific research and practical applications, such as improving early warning systems for geomagnetic storms and mitigating their potential impacts on Earth.

On the Azimuthal Flow of Protons in the Heavy Ion Collisions at $$\sqrt {{{s}_{{NN}}}} $$ = 2–4 GeV

On the Azimuthal Flow of Protons in the Heavy Ion Collisions at $$\sqrt {{{s}_{{NN}}}} $$ = 2–4 GeV

Carbon foam to enhance the performance of a slurry flow energy system used for hydrogen storage and transportation: An experimental investigation

A novel idea of using carbon foam (CF) is introduced to enhance the electrochemical performance of a slurry electrode system in a proton flow reactor system. Steam-activated and acid-washed Norit from peat is used as active charge carrier particles to prepare 15 wt% carbon slurry to be used in this study. The slurry flow rates in the experimental electrochemical system can be varied from 0 to 200 ml min−1, while using two channel widths of 1.6 cm and 2 cm to facilitate the slurry flow. Two sets of CFs with 10 pores per inch (PPI) and 5 PPI are used to understand the effect of introducing CFs with different pore sizes on the performance of slurry electrode. Slurry is charged slurry up to 100 C under constant application of 10 mA and 30 mA. After adding CF, the results show a significant drop in charging potential to generate both levels of current of 25% after using 5 PPI and 41% with 10 PPI. Furthermore, using the narrow channel flow of 1.6 cm and increasing the slurry flow rate from 100 ml min−1 to 150 ml min−1 lower the charging potential considerably by 19% and 21% (compared to base slurry) for 5 PPI and 10 PPI CF, respectively. Application of CF further enables the system to attain higher discharging time during the discharge cycle, and a maximum of 336% and 115% discharging capacity improvement is observed with 10 PPI and 5 PPI CF, respectively.

Bioinspired Water Preorganization in Confined Space for Efficient Water Oxidation Catalysis in Metallosupramolecular Ruthenium Architectures.

ConspectusNature has established a sustainable way to maintain aerobic life on earth by inventing one of the most sophisticated biological processes, namely, natural photosynthesis, which delivers us with organic matter and molecular oxygen derived from the two abundant resources sunlight and water. The thermodynamically demanding photosynthetic water splitting is catalyzed by the oxygen-evolving complex in photosystem II (OEC-PSII), which comprises a distorted tetramanganese-calcium cluster (CaMn4O5) as catalytic core. As an ubiquitous concept for fine-tuning and regulating the reactivity of the active site of metalloenzymes, the surrounding protein domain creates a sophisticated environment that promotes substrate preorganization through secondary, noncovalent interactions such as hydrogen bonding or electrostatic interactions. Based on the high-resolution X-ray structure of PSII, several water channels were identified near the active site, which are filled with extensive hydrogen-bonding networks of preorganized water molecules, connecting the OEC with the protein surface. As an integral part of the outer coordination sphere of natural metalloenzymes, these channels control the substrate and product delivery, carefully regulate the proton flow by promoting pivotal proton-coupled electron transfer processes, and simultaneously stabilize short-lived oxidized intermediates, thus highlighting the importance of an ordered water network for the remarkable efficiency of the natural OEC.Transferring this concept from nature to the engineering of artificial metal catalysts for fuel production has fostered the fascinating field of metallosupramolecular chemistry by generating defined cavities that conceptually mimic enzymatic pockets. However, the application of supramolecular approaches to generate artificial water oxidation catalysts remained scarce prior to our initial reports, since such molecular design strategies for efficient activation of substrate water molecules in confined nanoenvironments were lacking. In this Account, we describe our research efforts on combining the state-of-the art Ru(bda) catalytic framework with structurally programmed ditopic ligands to guide the water oxidation process in defined metallosupramolecular assemblies in spatial proximity. We will elucidate the governing factors that control the quality of hydrogen-bonding water networks in multinuclear cavities of varying sizes and geometries to obtain high-performance, state-of-the-art water oxidation catalysts. Pushing the boundaries of artificial catalyst design, embedding a single catalytic Ru center into a well-defined molecular pocket enabled sophisticated water preorganization in front of the active site through an encoded basic recognition site, resulting in high catalytic rates comparable to those of the natural counterpart OEC-PSII.To fully explore their potential for solar fuel devices, the suitability of our metallosupramolecular assemblies was demonstrated under (electro)chemical and photocatalytic water oxidation conditions. In addition, testing the limits of structural diversity allowed the fabrication of self-assembled linear coordination oligomers as novel photocatalytic materials and long-range ordered covalent organic framework (COF) materials as recyclable and long-term stable solid-state materials for future applications.

Fabrication of a hybrid device for the integration of light-triggered proton pumps

Biological ion pumps, such as bacteriorhodopsin (bR), utilize photons to move ions against concentration gradients, offering energy harvesting and spatiotemporal control of chemical gradients. This capability goes far beyond the capabilities of today's synthetic devices, suggesting a hybrid approach to embed bRs in synthetic devices in order to direct the proton flow towards useful system applications. In this study, a hybrid silicon-based nanochannel network with integrated purple membranes (PM) containing bR was fabricated. The fabrication method combines thermal scanning probe lithography, etching techniques, atomic layer deposition, plasma-enhanced chemical vapor deposition, and photolithography to create devices with buried nanochannels on silicon substrates. PM patches were deposited onto specified sites by a tunable nanofluidic confinement apparatus. The resulting device holds the potential for locally controlling directed ion transport in micrometer scale devices, a first step towards applications, such as locally affected proton catalyzed chemical reaction networks. Furthermore, this fabrication strategy, employing a maskless overlay, is a tool for constructing intricate nanofluidic network designs which are mechanically robust and straightforward to fabricate.

The use of NADH anisotropy to investigate mitochondrial cristae alignment

Life may be expressed as the flow of electrons, protons, and other ions, resulting in large potential difference. It is also highly photo-sensitive, as a large proportion of the redox capable molecules it relies on are chromophoric. It is thus suggestive that a key organelle in eukaryotes, the mitochondrion, constantly adapt their morphology as part of the homeostatic process. Studying unstained in vivo nano-scale structure in live cells is technically very challenging. One option is to study a central electron carrier in metabolism, reduced nicotinamide adenine dinucleotide (NADH), which is fluorescent and mostly located within mitochondria. Using one and two-photon absorption (340–360 nm and 730 nm, respectively), fluorescence lifetime imaging and anisotropy spectroscopy of NADH in solution and in live cells, we show that mitochondria do indeed appear to be aligned and exhibit high anisotropy (asymmetric directionality). Aqueous solution of NADH showed an anisotropy of ~ 0.20 compared to fluorescein or coumarin of < 0.1 and 0.04 in water respectively and as expected for small organic molecules. The anisotropy of NADH also increased further to 0.30 in the presence of proteins and 0.42 in glycerol (restricted environment) following two-photon excitation, suggesting more ordered structures. Two-photon NADH fluorescence imaging of Michigan Cancer Foundation-7 (MCF7) also showed strong anisotropy of 0.25 to 0.45. NADH has a quantum yield of fluorescence of 2% compared to more than 40% for photoionisation (electron generation), when exposed to light at 360 nm and below. The consequence of such highly ordered and directional NADH patterns with respect to electron ejection upon ultra-violet (UV) excitation could be very informative—especially in relation to ascertaining the extent of quantum effects in biology, including electron and photonic cascade, communication and modulation of effects such as spin and tunnelling.

Dual-Stimuli-Responsive Modulation Organic Afterglow Based on N─H Proton Migration Mechanism.

Organic afterglow materials have significant applications in information security and flexible electronic devices with unique optical properties. It is vital but challenging to develop organic afterglow materials possessing controlled output with multi-stimuli-responsive capacity. Herein, dimethyl terephthalate (DTT) is introduced as a strong proton acceptor. The migration direction of N─H protons on two compounds Hs can be regulated by altering the excitation wavelength (Ex) or amine stimulation, thereby achieving dual-stimuli-responsive afterglow emission. When the Ex is below 300nm, protons migrate to S1-2 DTT, where strong interactions induce phosphorescent emission of Hs, resulting in afterglow behavior. Conversely, when the Ex is above 300nm, protons interact with the S0 DTT weakly and the afterglow disappears. In view of amine-based compounds with higher proton accepting capabilities, it can snatch proton from S1-2 DTT and redirect the proton flow toward amine, effectively suppressing the afterglow but obtaining a new redshifted fluorescence emission with Δλ over 200nm due to the high polarity of amine. Moreover, it is successfully demonstrated that the applications of dual-stimuli-responsive organic afterglow materials in information encryption based on the systematic excitation-wavelength-dependent (Ex-De) behavior and amine selectivity detection.

A mathematical modeling of the mitochondrial proton leak via quantum tunneling

&lt;abstract&gt; &lt;p&gt;The mitochondrion is a vital intracellular organelle that is responsible for ATP production. It utilizes both the concentration gradient and the electrical potential of the inner mitochondrial membrane to drive the flow of protons from the intermembrane space to the matrix to generate ATP via ATP-synthase. However, the proton leak flow, which is mediated via the inner mitochondrial membrane and uncoupling proteins, can reduce the efficiency of ATP production. Protons can exhibit a quantum behavior within biological systems. However, the investigation of the quantum behavior of protons within the mitochondria is lacking particularly in the contribution to the proton leak. In the present study, we proposed a mathematical model of protons tunneling through the inner mitochondrial membrane and the mitochondrial carrier superfamily MCF including uncoupling proteins UCPs and the adenine nucleotide translocases ANTs. According to the model and its assumptions, the quantum tunneling of protons may contribute significantly to the proton leak if it is compared with the classical flow of protons. The quantum tunneling proton leak may depolarize the membrane potential, hence it may contribute to the physiological regulation of ATP synthesis and reactive oxygen species ROS production. In addition to that, the mathematical model of proton tunneling suggested that the proton-tunneling leak may depolarize the membrane potential to values beyond the physiological needs which in turn can harm the mitochondria and the cells. Moreover, we argued that the quantum proton leak might be more energetically favorable if it is compared with the classical proton leak. This may give the advantage for quantum tunneling of protons to occur since less energy is required to contribute significantly to the proton leak compared with the classical proton flow.&lt;/p&gt; &lt;/abstract&gt;

Tomato and mini-cucumber tolerance to photoperiodic injury involves photorespiration and the engagement of nighttime cyclic electron flow from dynamic LEDs.

Controlled environment agriculture (CEA) is critical for achieving year-round food security in many regions of the world. CEA is a resource-intensive endeavor, with lighting consuming a large fraction of the energy. To lessen the burden on the grid and save costs, an extended photoperiod strategy can take advantage of off-peak time-of-day options from utility suppliers. However, extending the photoperiod limits crop production morphologically and physiologically if pushed too long. Here, we present a continuous-light dynamic light-emitting diode (LED) strategy (involving changes in spectra, intensity, and timing), that overcomes these limitations. We focused on tomato, a well described photoperiodic injury-sensitive species, and mini-cucumber, a photoperiodic injury-tolerant species to first assess morphological responses under control (16-h photoperiod, unchanging spectrum), constant (24-h photoperiod, unchanging spectrum), and two variations of a dynamic LED strategy, dynamic 1 (16-h "day", 3-h "peak", 8-h "night" spectra) and dynamic 2 (20-h "day", 5-h "peak", 4-h "night" spectra). Next, we tested the hypothesis of photorespiration's involvement in photoperiodic injury by using a leaf gas exchange coupled with chlorophyll fluorescence protocol. We further explored Adenosine triphosphate (ATP): Nicotinamide adenine dinucleotide phosphate (NADPH) ratio supply/demand responses by probing photosynthetic electron flow and proton flow with the MultispeQ instrument. We found canopy architecture can be tuned by minor variations of the same dynamic LED strategy, and we highlight dynamic 1 as the optimal choice for both tomato and mini-cucumber as it improved biomass/architecture and first-yield, respectively. A central discovery was that dynamic 1 had a significantly higher level of photorespiration than control, for both species. Unexpectedly, photorespiration was comparable between species under the same treatments, except under constant. However, preliminary data on a fully tolerant tomato genotype grown under constant treatment upregulated photorespiration similar to mini-cucumber. These results suggest that photoperiodic injury tolerance involves a sustained higher level of photorespiration under extended photoperiods. Interestingly, diurnal MultispeQ measurements point to the importance of cyclic electron flow at subjective nighttime that may also partially explain why dynamic LED strategies mitigate photoperiodic injury. We propose an ontology of photoperiodic injury involving photorespiration, triose phosphate utilization, peroxisomal H2O2-catalase balance, and a circadian external coincidence model of sensitivity that initiates programmed cell death.

Directed flow and hyperon polarization at RHIC BES from multi-fluid dynamics

We present directed flow of protons and pions, as well as mean polarization of Λ and ¯Λ hyperons computed for Au-Au collisions at √SNN = 5 … 19.6 GeV in MUFFIN model. MUlti Fluid simulation for Fast IoN collisions, or MUFFIN, is a state-of-the-art 3-fluid dynamic model for simulating heavy-ion collisions in the region from a few to a hundred GeV center-of-mass energy. Whereas MUFFIN succeeds to reproduce basic observables in the collision energy range of interest, the slope of the directed flow at mid-rapidity is much steeper as compared to the data, it has unclear EoS dependence and final-state hadronic cascade affects this observable significantly. The excitation function of the Λ polarization shows a significant splitting between polarizations of Λ and ¯Λ, which challenges a widespread interpretation that the splitting is affected mainly by the late-stage magnetic field.

Mathematical Model for Chemical Reactions in Electrolytes Applied to Cytochrome c Oxidase: An Electro-Osmotic Approach

This study introduces a mathematical model for electrolytic chemical reactions, employing an energy variation approach grounded in classical thermodynamics. Our model combines electrostatics and chemical reactions within well-defined energetic and dissipative functionals. Extending the energy variation method to open systems consisting of charge, mass, and energy inputs, this model explores energy transformation from one form to another. Electronic devices and biological channels and transporters are open systems. By applying this generalized approach, we investigate the conversion of an electrical current to a proton flow by cytochrome c oxidase, a vital mitochondrial enzyme contributing to ATP production, the ‘energetic currency of life’. This model shows how the enzyme’s structure directs currents and mass flows governed by energetic and dissipative functionals. The interplay between electron and proton flows, guided by Kirchhoff’s current law within the mitochondrial membrane and the mitochondria itself, determines the function of the systems, where electron flows are converted into proton flows and gradients. This important biological system serves as a practical example of the use of energy variation methods to deal with electrochemical reactions in open systems. We combine chemical reactions and Kirchhoff’s law in a model that is much simpler to implement than a full accounting of all the charges in a chemical system.

A STUDY OF IMPROVEMENT OF A TECHNOLOGY FOR OBTAINING RADIATION-PROTECTING MATERIALS FOR SPACECRAFT AND ROCKETRY SYSTEMS

&#x0D; &#x0D; &#x0D; Abstract. The use of commercial integrated circuits (ICs) in the electronic equipment of the spacecraft entails a certain risk. This is due to the fact that some commercial ICs are not suitable for operating conditions in space, most have a functional failure rate of about 10 krad per total accumulated dose (ie quite low), durability is not controlled from lot to lot, and reliability in extreme operating conditions is not defined. The object of development and research were the processes of interaction of materials with corpuscular radiation in a wide range of energies, and the subject of research was the shielding of electron and proton flows with energies up to 100 MeV by disperse -filled composite materials with a polymer matrix. A promising way to increase the survivability of the spacecraft by reducing the accumulated radiation dose is the use of protective materials that effectively protect the BEA from the radiation flow. The analysis of the current state of protection of radio- electronic equipment of space technology made it possible to establish that the most effective protection can be achieved by optimally combining the content of light and heavy elements in the composite material (CM). Modern research is aimed at obtaining composite materials that have the ability to weaken and disperse both light and heavy elementary particles. In the State University named after O. Honchar developed fundamentally new composite materials, which are superior in protection efficiency to those used today - metal ones, and are not inferior to the best world analogues. Preliminary results of theoretical and experimental research, including the use of computer modeling and simulation experiments on electron and proton accelerators, made it possible to draw conclusions about the possibility of increasing the complex of protective properties and prospects of the materials being created. The flow of high-energy electrons decreases by 1.4 times, and protons by 1.6 times compared to aluminum alloys. Enterprises of the space industry of Ukraine have shown great interest in the use of new protective materials. Analysis of the available information shows that the created materials are superior in operational parameters to those used today in China, Russia, Ukraine and other space countries. According to theoretical calculations, CM samples were developed, which have a higher stopping power of electrons than aluminum or its alloys, which are currently used in space vehicles in almost the entire range of the spectrum characteristic of GSO. Studies using the ELIAS linear electron accelerator showed that the obtained KM samples are more than 1.3 times more effective in terms of protective properties compared to aluminum at electron energies of the order of 2-3 MeV . There are prerequisites for obtaining an even more effective attenuation of the electron flow in comparison with the "reference" aluminum due to the variation of both the qualitative composition of the CM and its structure.&#x0D; &#x0D; &#x0D;

QCD Equation of State of Dense Nuclear Matter from a Bayesian Analysis of Heavy-Ion Collision Data.

Bayesian methods are used to constrain the density dependence of the QCD equation of state (EOS) for dense nuclear matter using the data of mean transverse kinetic energy and elliptic flow of protons from heavy ion collisions (HICs), in the beam energy range sqrt[s_{NN}]=2-10 GeV. The analysis yields tight constraints on the density dependent EOS up to 4 times the nuclear saturation density. The extracted EOS yields good agreement with other observables measured in HIC experiments and constraints from astrophysical observations both of which were not used in the inference. The sensitivity of inference to the choice of observables is also discussed.

High-Energy Radiation Effects on Silicon NPN Bipolar Transistor Electrical Performance: A Study with 1 MeV Proton Irradiation.

This study investigates the degradation of the silicon NPN transistor's emitter-base junction, specifically the 2N2219A model, under both forward and reverse polarization. We examine the current-voltage characteristics under the influence of 1 MeV proton irradiation at various fluencies, which are 5.3×108,5.3×1010,5×1011,5×1012, and 5×1013 protons/cm², all conducted at 307 K. The experimental findings elucidate a pronounced dependency of diode parameters, including the reverse saturation current, series resistance, and the non-idealist factor, on the incident proton flow. This observation underscores that proton-induced degradation is primarily driven by displacement damage, while recorded degradation is predominantly attributed to the generation of defects and interfacial traps within the transistor resulting from exposure to high-energy radiation. Our findings indicate that the effects of irradiation align more closely with the compensation phenomenon in doping rather than its reinforcement.

Magnetic Reconnection in the Martian Magnetotail: Occurrence Rate and Impact on Ion Loss

AbstractThe current sheet is crucial in releasing magnetic free energy in cosmic plasmas via fast magnetic reconnection or wave excitation. This research investigates the characteristics of the Martian tail current sheet by analyzing data acquired from the Mars Atmosphere and Volatile EvolutioN spacecraft over 7 years. For the first time, we find that approximately 15% of the current sheet events display reconnection signatures, including Hall magnetic fields and fast proton flows. These reconnecting current sheets are detected more frequently on Mars than on Earth. The Martian tail current sheet is first demonstrated to be on the proton scale, which can explain the high reconnection occurrence rate. The research also reveals that the current sheets are thinner in regions closer to Mars and in the –E hemisphere. On average, reconnecting current sheets carry high fluxes of protons rather than oxygen ions.

Maintaining immune homeostasis with Coptis Chinensis water extract to mitigate sepsis severity via modulating gut microbiome and metabolism

Sepsis arises from an uncontrolled inflammatory response to infection that can lead to organ failure. The gut microbiome is increasingly recognized as a key modulator of sepsis progression. This study investigated whether Coptis chinensis water extract (CCWE) could attenuate sepsis by modulating the gut microbiome and immune response. A rat model of sepsis induced by cecum ligation and perforation was used. 16 S ribosomal ribonucleic acid (rRNA) sequencing, proton nuclear magnetic resonance (1H NMR) metabolomics and flow cytometry assays were used to evaluate microbial, metabolic and immune profiles. CCWE treatment reversed sepsis-induced loss of beneficial bacteria like Firmicutes and Bacteroidetes and restored gut microbial balance. CCWE increased short-chain fatty acids, carnitine and phenylacetate, which provide energy and curb inflammation. By enhancing immune homeostasis and maintaining regulatory T cells (Tregs), CCWE treatment also exerted bidirectional regulation on T cells for initially suppressing hyperactivation then enabling recovery. Overall, CCWE may benefit sepsis by regulating the gut-microbiome-immune axis. By restoring microbiome balance, improving metabolism, and modulating immunity, CCWE treatment shows potential for alleviating sepsis severity and progression. The increases in beneficial bacteria, Tregs, and anti-inflammatory metabolites coupled with decreases in opportunistic pathogens likely contributed collectively to CCWE's protective effects. CCWE may emerge as an alternative or adjunctive option for managing disorders of dangerous inflammation like sepsis. Future research should explore CCWE's mechanisms of action clinically to determine its potential as a safe, effective means of modulating health through natural regulation of the gut microbiome and immune function.

ATP modulates the activity of the voltage-gated proton channel through direct binding interaction.

ATP is an important molecule implicated in diverse biochemical processes, including the modulation of ion channel and transporter activity. The voltage-gated proton channel (Hv1) controls proton flow through the transmembrane pathway in response to membrane potential, and various molecules regulate its activity. Although it is believed that ATP is not essential for Hv1 activity, a report has indicated that cytosolic ATP may modulate Hv1. However, the detailed molecular mechanism underlying the effect of ATP on Hv1 is unknown, and whether ATP is involved in the physiological regulation of Hv1 activity remains unclear. Here, we report that cytosolic ATP is required to maintain Hv1 activity. To gain insight into the underlying mechanism, we analysed the effects of ATP on the mouse Hv1 channel (mHv1) using electrophysiological and microscale thermophoresis (MST) methods. Intracellular ATP accelerated the activation kinetics of mHv1, thereby increasing the amplitude of the proton current within the physiological concentration range. The increase in proton current was reproduced with a non-hydrolysable ATP analogue, indicating that ATP directly influences Hv1 activity without an enzymatic reaction. The direct molecular interaction between the purified mHv1 protein and ATP was analysed and demonstrated through MST. In addition, ATP facilitation was observed for the endogenous proton current flowing through Hv1 in the physiological concentration range of ATP. These results suggest that ATP influences Hv1 activity via direct molecular interactions and is required for the physiological function of Hv1. KEY POINTS: We found that ATP is required to maintain the activity of voltage-gated proton channels (Hv1) and investigated the underlying molecular mechanism. Application of intracellular ATP increased the amplitude of the proton current flowing through Hv1, accompanied by an acceleration of activation kinetics. The direct interaction between purified Hv1 protein and ATP was quantitatively analysed using microscale thermophoresis. ATP enhanced endogenous proton currents in breast cancer cell lines. These results suggest that ATP influences Hv1 activity via direct molecular interactions and that its functional characteristics are required for the physiological activity of Hv1.