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The interactions between ionic charge carriers and host framework critically govern electrochemical reactions and ion-storing performance, serving as a pivotal design consideration for energy storage devices. However, the fundamental understanding of the covalent-ionic interactions between anion and oxidized π+-framework remains limited thus far. Here we reveal the covalent-ionic nature of anion-π+ interactions between poly(arylamine)s (PAAs) and Cl- anions. Cl--π+ complexes bearing rigid polymeric aryl-substituted dihydrophenazine (PDPZ) exhibit both electrostatic interaction and distinct Cl-→π+ charge-transfer orbital contribution, confirming the underlying hybrid covalent-ionic nature of Cl--π+ interaction. The synergistic effect of Cl--π+ interaction and high electron delocalization capability of PDPZx+ framework enables reversible Cl- intercalation/deintercalation during multi-electron redox, achieving a high anion storage capacity of 236 mAh g-1 and remarkable energy densities of 175 Wh kg-1 (Zn||PDPZ cell, in 30 m ZnCl2), alongside long calendar life as cathodes for Cl--based dual-ion batteries (Cl-DIBs). Spectroscopic evidence reveals dynamic evolution of vibrational modes and electronic structures from PDPZ to PDPZx+·xCl- complexes, demonstrating the entire π+-framework participation and anion-to-π+ charge transfer during chloride storage. Our mechanistic insights into anion-π+ interactions in Cl-DIBs provide theoretical guidance for designing advanced anion-storage organic cathodes and advance anion coordination chemistry.

"Chemistry is fun because it gives us the power to rationally design and create molecules and materials that would otherwise not exist in nature… I advise my students to analyze and understand failed experiments to shape their chemical intuition, rather than simply abandon unexpected/unwanted results." Find out more about Xiaoran Hu in his Introducing… Profile.

The plant microbiome plays a crucial role in enhancing disease resistance, yet microbiome-based plant protection strategies remain limited by an incomplete understanding of how host selection, microbial interactions, and rhizosphere chemistry jointly shape pathogen suppression. Here, we adopt a "learning from nature" approach to design synthetic microbial communities (SynComs) that recapitulate naturally evolved disease-suppressive interactions, using banana Fusarium wilt as a model system. High-throughput profiling revealed that both bacterial and fungal communities contribute to varietal resistance. Resistance-associated microbial taxa were identified and isolated to assemble bacterial, fungal, and cross-kingdom SynComs representative of resistant versus susceptible hosts. SynComs derived from resistant varieties suppressed pathogen growth more effectively than those from susceptible hosts, with cross-kingdom SynComs exhibiting the strongest effects. Cross-kingdom SynCom inoculation significantly reduced disease severity and restructured both the composition and functional potential of the rhizosphere microbiome. Integrative transcriptomic and metabolomic analyses revealed coordinated host metabolic reprogramming, characterized by increased accumulation of diverse metabolites, including alkaloids, amino acids, and flavonoids. Notably, supplementation with resistance-associated rhizosphere metabolites, such as stearic acid and shikimic acid, further enhanced disease suppression. Together, our findings establish a mechanistic framework in which host-guided microbiome assembly and metabolite-mediated interactions jointly enable effective cross-kingdom SynComs for disease suppression, providing ecological principles for microbiome-based plant protection strategies. Video Abstract.

Carbon quantum dots represent a new class of green nanomaterials with exceptional catalytic efficiency and excellent biocompatibility. In this study, a sustainable and green synthetic protocol has been developed using biomass-derived carbon quantum dots obtained from Butea monosperma bark as a green nanocatalyst. The catalyst was comprehensively analyzed using HRTEM, SAED, EDX, FT-IR, XRD, UV-visible, and fluorescence spectroscopy, confirming its amorphous nature, surface functionalization, and optical properties, with an average particle diameter of 5.78 nm. The catalyst was successfully utilized for the preparation of a diverse library of benzopyran derivatives via the reaction of substituted salicylaldehydes with various C-H activated compounds. The reactions were carried out under mild conditions using EtOH/H2O (1 : 1) solvent system at room temperature. A diverse library of 17 benzopyran derivatives was synthesized in excellent yields (83-97%) within short reaction times (10-35 min). The catalyst showed remarkable tolerance toward both electron-withdrawing and electron-donating substituents, demonstrating its broad substrate scope and selectivity. The catalyst exhibited excellent recyclability for up to seven consecutive cycles with minimal loss of catalytic activity and favourable green chemistry metrics. Furthermore, in silico studies were conducted to evaluate the biological potential of the synthesized compounds against neuropeptide Y5 receptor antagonists, kinase inhibition, and testosterone 17β-dehydrogenase (NADP+). Among them, compounds 3j, 3i, and 3q showed the most promising binding affinities with docking scores of -18.91, -14.35, and -19.49 kcal mol-1, respectively. Key features of the developed protocol include novel source of biomass utilization, metal-free catalysis, operational simplicity, ambient reaction conditions, recyclability and high sustainability.

Metal-mediated hydrogen atom transfer (MHAT) enables versatile radical hydrofunctionalization reactions, yet asymmetric variants, especially for olefin-olefin coupling, remain unknown with small-molecule catalysts. Here we report an enzymatic solution using engineered protoglobins, establishing a biocatalytic platform for asymmetric MHAT-triggered intramolecular cyclization. Directed evolution of a protoglobin furnished a variant that catalyzes 5-exo-trig radical cyclizations to generate 3,4-substituted pyrrolidines in high yields and up to 98:2 e.r. The reaction tolerates diverse donor and acceptor substituents, including esters, amides, nitriles, nitro groups, imines, and ketones. Mechanistic experiments and DFT calculations support a radical pathway with an ultrafast enantiodetermining radical cyclization. These results show that engineered heme proteins can support new-to-nature MHAT chemistry and exert stereocontrol over rapid radical steps, providing a powerful system for asymmetric MHAT reactions.

Allenes and alkynes are versatile functional groups in total synthesis, medicinal chemistry, and bioorthogonal conjugation. The biosynthetic logic of how Nature installs allene or alkyne in natural products, especially that of allenes, is not well understood. Here we uncovered allenes and alkynes can be formed enzymatically through oxidative C( sp 2 )-demethylation of the common five-carbon prenyl group. Two fungal cytochrome P450 monooxygenases, PpnB and NseB, from the penipratynolene and sinuxylamide biosynthetic pathways, respectively, were shown to catalyze oxidative removal of a C( sp 2 )-methyl group in O -prenyl-L-tyrosine to afford O -homoallenyl-L-tyrosine and O -but-2-ynyl-L-tyrosine, respectively. Combining density functional theory calculations, heterologous expression, biotransformation and enzymatic assays with isotopically labeled substrates, a mechanism involving selective C-C bond cleavage followed by product-determining hydrogen atom abstraction is presented. An additional P450 enzyme from the penipratynolene pathway, PpnD, acts as an oxidative isomerase that converts the four-carbon terminal allene into a terminal alkyne. This unprecedented enzymatic editing strategy to install allene and alkyne expands the catalytic repertoire of P450 enzymes.

Plasmon-driven reduction of 4-nitrobenzenethiol (4-NBT) has been linked experimentally to transient negative ions and nonthermal multiquantum vibrational excitation, yet the molecular nature of the electronically excited anionic state involved in this process remains unclear. Here, we present a time-dependent density functional theory (TD-DFT) study of the Au5-4-NBT complex to examine how hot-electron injection accesses a low-lying excited anionic manifold and how these states couple to vibrational motion. Our results identify a low-lying quartet excited anionic state, denoted Q1, that becomes energetically accessible in the Au5-4-NBT complex under plasmon-driven vertical electron attachment (VEA) conditions. Natural transition orbital analysis shows that Q1 has mixed local-excitation and charge-transfer character, while comparison with free 4-NBT indicates that gold coordination reorganizes and lowers the relevant excited-state manifold. Vibronically resolved one-photon absorption (OPA) calculations show that access to Q1 is strongly influenced by the NO2 symmetric stretching coordinate, and one-photon emission (OPE) calculations indicate that the same coordinate also plays an important role in a possible radiative decay channel from Q1. Potential-energy profile analysis further identifies low-energy crossing regions along the NO2 coordinate that are consistent with vibronically assisted access to the excited anionic manifold. Taken together, these results provide a molecular-level framework for interpreting the transient anionic state and nonthermal multiquantum vibrational excitation proposed experimentally for plasmon-driven 4-NBT chemistry.

An efficient synthetic route was developed for indeno[1,2-d]pyrimidinone and indeno[1,2-d]pyrimidinethione derivatives via a modified Biginelli condensation of aryl aldehydes, 5-chloroindanone, and urea/thiourea. The reaction, catalyzed by recyclable calcium silicate, proceeded under mild conditions to afford the target compounds in good to high yields, with the catalyst maintaining activity over multiple cycles. The catalyst was characterized using powder x-ray diffraction, scanning electron microscopy, and transmission electron microscopy to confirm its structural integrity. The molecular structures of the synthesized derivatives were supported by proton nuclear magnetic resonance, infrared spectroscopy, and mass spectrometry. Green chemistry metrics, including atom economy, reaction mass efficiency, and E-factor, were used to evaluate the sustainability of the developed synthetic protocol. Density functional theory calculations provided insights into the electronic properties of the compounds. Preliminary and complementary biological studies, including cytotoxicity screening, DNA binding, and cleavage, were carried out to explore potential biological behavior. Preliminary molecular docking with A/B -DNA was also performed to provide a tentative understanding of possible interactions. A predictive structure-activity trend analysis was carried out to correlate structural features with observed trends in cytotoxicity. These biological evaluations are exploratory in nature, intended for the identification of promising leads for further study.

Artificial metalloenzymes (ArMs) expand the suite of synthetically valuable, new-to-nature biocatalytic reactions. Integrating these enzymes into biosynthetic pathways enables reactions not found in nature to occur in living cells with the intermediates or products of the metabolic pathways. However, the integration of reactions catalyzed by ArMs into complex metabolic pathways is constrained by the lack of methods to assemble these ArMs in organisms that are commonly used for metabolic engineering. We report the assembly of an iridium-containing artificial metalloenzyme (Ir-ArM) in Streptomyces albus, a Gram-positive bacterial chassis widely used for the heterologous expression of natural products. In this engineered organism, the Ir-ArM assembles in the cytoplasm and catalyzes abiological carbene transfer to the unactivated, disubstituted double bond of an exogenously added terpene with turnover numbers (TONs) that are two times higher than those for the same reaction catalyzed within E. coli cells harboring Ir-ArM and 20 times higher than the TONs for the same reaction catalyzed by the purified holoprotein itself.

Metabolic syndrome (MetS) is a group of interrelated metabolic aberrations that significantly elevates the risk of poor cardiovascular outcomes and type 2 diabetes mellitus. Healthcare professionals, particularly those working long shifts, may have elevated risk due to the demanding nature of their work, irregular lifestyles, and associated stress. This study aimed to assess the prevalence and associated factors of MetS among healthcare professionals working long shifts in primary hospitals in the Central Gondar Zone, Northwest Ethiopia. An institutional-based cross-sectional study was conducted among a total of 271 healthcare professionals working in three primary hospitals (from September to December 2023). Study data were collected using structured questionairs, anthropometric measurements, and biochemical assessments. Five mililiters of fasting blood sample was collected from each participant; and serum lipid profile and glucose analyzed on Beckman Coulter DXC 700 AU chemistry analyzer. MetS was defined using the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria. Independent ttest and one-way ANOVA were used for intra and inter group comparison; and Logistic regression model was fitted to identify factors associated with MetS, and adjusted odds ratios (AORs) with 95% confidence intervals (CIs) were reported to determine the strength of associations. The prevalence of MetS among healthcare professionals was 11.44% (95% CI 8.14-15.83). Dyslipidemias were observed to be the most common forms of metabolic derangement with 145 (53.51%) of study subjects having at least one lipid profile abnormality; whereas, hyperglycemias was the least common 27 (9.96%) form of metabolic abnormalities. Age&#x2009;&#x2265;&#x2009;35 years (AOR&#x2009;=&#x2009;6.75; 95% CI: 2.34-19.46), a family history of diabetes among first-degree relatives (AOR&#x2009;=&#x2009;7.78; 95% CI: 2.57-23.53), and short sleep duration (<6 hours per day) (AOR&#x2009;=&#x2009;7.78; 95% CI: 2.35-25.70) were significant factors associated with MetS (p&#x2009;<&#x2009;0.05). Metabolic syndrome is prevalent among healthcare professionals particularily those working long shifts; with age, family history of diabetes, and insufficient sleep identified as key risk factors. Hospital administrators and occupational health units should implement routine metabolic screening, optimized shift scheduling, and sleep hygiene support programs specifically for healthcare professionals working prolonged shifts, with particular attention to high-risk staff groups. Further workplace-based research is also needed to evaluate the effectiveness of these targeted interventions.

Despite the ubiquitous nature of alkyne-transition metal complexes in synthesis and catalysis, analogous examples for the heavier group 14 elements are extremely rare. Here, we describe access to the first such species for Sn and Pb in nickel(0) complexes, [(CyLE)2&#xb7;Ni] (5 and 6; CyL = [{Cy2PCH2Si(iPr)2}(Dipp)N]-; Dipp = 2,6-iPr2C6H3). Although these systems cannot be accessed by direct addition of the EI dimers to a Ni0 synthon (i.e. Ni(cod)2; cod = 1,5-cyclooctadiene), we report a novel reductive group elimination pathway, forming the EI dimers from EII synthons in the coordination sphere of Ni, for example, through H2 elimination from SnII hydride compounds. Structural analyses in combination with computational studies indicate that these species are best described as &#x3c3;-complexes of EI dimers with a transition metal centre, representing a new bonding mode in organometallic coordination chemistry.

Glioblastoma multiforme (GBM) is the most common and aggressive primary malignant brain tumor. Despite combined treatments, including surgical removal followed by radiation and chemotherapy, the prognosis remains poor. Even with temozolomide, the current standard for GBM treatment, the disease is still incurable because of GBM's highly invasive nature and resistance to therapy. This review examines the contributions of key DNA repair pathways, including O6-methylguanine-DNA methyltransferase, base excision repair, and homologous recombination, to the resolution of DNA lesions induced by therapy. It also highlights emerging molecular therapeutic targets that exploit synthetic lethality to enhance treatment efficacy. In addition, the review explores other determinants of GBM resistance, such as oncogenic genetic mutations, the tumorigenic glioma stem cells (GSCs), metabolic reprogramming within the tumor microenvironment that promotes immune evasion, and the restrictive nature of the blood-brain barrier, which limits effective drug intratumoral concentrations. Finally, we discuss patient-specific immunotherapeutic strategies, including chimeric antigen receptor T (CAR-T) cell therapy and personalized cancer vaccines, which hold promise for improving survival outcomes across different GBM subtypes. Advances in multi-omics profiling and machine learning are reshaping opportunities for personalized therapy in GBM. Integrating WES, RNA-seq, and HLA typing enables tailored immunotherapies, while AI-driven antibody design accelerates the development of GSC-targeting candidates. Yet translation remains hindered by GBM's heterogeneity, limited patient availability, and disparities in trial participation. Progress will require combining mechanistic tumor profiling with computational design approaches within more inclusive clinical trials to advance truly personalized and effective GBM treatment.

In cancer therapy, traditional approaches often overlook the dynamic nature of drug-target interactions. We introduce kinetic fingerprints as a mechanistically informative tool to guide kinase inhibitor design and predict clinical performance. Profiling 172 compounds across multiple KIT conformations, including the oncogenic D816V mutation, show that prolonged residence time determines therapeutic success, while mutations accelerating dissociation rates (koff) drive resistance, positioning koff as a robust predictor of clinical failure. Beyond efficacy and resistance, kinetic signatures map molecular behavior: fast-associating scaffolds engage readily populated KIT states, slow binders overcome conformational barriers like juxtamembrane repositioning, and extended residence times highlight ligands stabilizing regulatory elements (G-loop and regulatory spine). Kinetic profiling further unveils mechanisms invisible to conventional methods, such as drug-induced kinase degradation, and exposes selectivity dimensions beyond affinity: avapritinib exhibits durable KIT D816V engagement yet transient off-target binding. Our findings redefine the evaluation of KIT inhibitors, establishing a framework for rational, kinetics-guided drug discovery in KIT-driven cancers.

Airborne bacteria significantly influence the environment, climate, and public health. The nature and extent of these impacts, however, can vary depending on bacterial viability. To understand the sources and controlling factors of viable and non-viable bacteria in coastal aerosols, we investigated their temporal variations, cell size distributions, and enrichment during sea-to-air transfer at Wanshan Island, southern China. Viable bacteria in aerosols showed strong correlations with those in seawater in both concentration (r&#x202f;=&#x202f;0.783) and cell size distribution, indicating a dominant seawater origin. Their emission was jointly enhanced by seawater viable bacterial abundance and chlorophyll a (r&#x202f;=&#x202f;0.910). In contrast, non-viable bacteria showed no such correlation and exhibited distinct size patterns, and were primarily influenced by rainfall, sea surface temperature, and relative humidity, suggesting they are controlled by atmospheric physical processes. During sea-to-air transfer, viable bacteria were preferentially enriched with an enrichment factor of 236 compared to non-viable bacteria (143). Although viable bacteria account for only 13% of total bacteria in seawater, their contribution to the emission flux rises to approximately 20% (18.4&#x202f;cells m-2 s-1). The estimated viable bacterial productivity flux is 2.3&#x202f;&#xd7;&#x202f;10-7&#x202f;g&#x202f;C m-2 d-1. Given the higher enrichment of viable bacteria in sea spray aerosols, their potential contribution to ice nucleation and cloud condensation processes in coastal regions needs further investigation. These findings highlight the importance of distinguishing between viable and non-viable bacteria in assessing marine microbial impacts on atmospheric chemistry, carbon cycling, and climate.

The relatively richer reservoir and reasonable performance in activating C&#x2500;H bonds make cobalt a very competitive catalyst for the oxidative dehydrogenation of propane with carbon dioxide (CO2-ODP). However, the catalytic nature of different cobalt species is ambiguous, and the development of active and selective Co-based CO2-ODP catalysts are at the very early stage. In this study, Co species on CoOx/Silicalite-1 catalysts are regulated by calcining the catalyst precursor at 500&#xb0;C under Ar, Air, and H2 atmospheres, respectively. Characterization results reveal that the proportion of Co3O4 spinel, metallic Co, and tetrahedrally coordinated Co2+ species (Td-Co2+) is easily altered by changing the calcining atmosphere. Moreover, Td-Co2+ is revealed to be the active site for CO2-ODP while Co0 is active for side reactions such as cracking and reforming. As a result of the richest Td-Co2+ and diminished Co0 over the CoOx/Silicalite-1 catalyst calcined in Ar, the highest CO2-ODP performance is achieved with a propylene space-time yield of 15.88 mmol&#xb7;gcat -1&#xb7;h-1. Besides acting as a mild oxidant, the additional functions of CO2 are to retard the reduction of Td-Co2+ and to reduce the coke accumulation via the reverse Boudouard reaction during CO2-ODP. These understandings are important guides for optimizing with more efficient Co-based CO2-ODP catalyst.

Protein biosynthesis represents a key target for anti-tubercular drug design. Tryptophanyl-tRNA synthetase (TrpRS) is an essential enzyme in Mycobacterium tuberculosis (M.tb) that is involved in translation. Here, we investigate how TrpRS recognizes the substrate-intermediate versus inhibitors and find essential physicochemical features relevant for inhibitor design. We performed systematic molecular dynamics simulations for 24 microseconds across eight TrpRS states, including the apo form, the substrate intermediate, and six indolmycin-based inhibitor-bound states. The substrate-intermediate state was less stable than the inhibitor-bound states, consistent with its transient nature. Inhibitors act by stabilizing the ATP conformation within the TrpRS binding site, whereas compounds that disrupt ATP conformation and its interactions with TrpRS show reduced inhibitory activity. Using data of 28 indolmycin-based inhibitors, we developed simple two-property models (R&#xa0;=&#xa0;0.82-0.88, p&#xa0;<&#xa0;0.01) defining the TrpRS inhibitory activity based on electron affinity/solubility and ensemble ligand docking, and further derived a six-feature pharmacophore framework for inhibitor design. TrpRS inhibition was successfully explained by ensemble docking using four TrpRS structures, yielding a correlation coefficient of 0.77 (p&#xa0;<&#xa0;0.01). These results provide mechanistic insight into TrpRS function and support structure-guided antitubercular drug design.

Anthropogenic carbon dioxide emissions remain a critical driver of climate change, necessitating the development of efficient carbon capture technologies. While aqueous amines are widely used, they suffer from high regeneration energies and solvent degradation. Here, we report a nonaqueous, cooperative CO2 absorption system using 1-methylpiperazine (MPZ) dissolved in a family of aromatic additives. Among these, the formulation with 2'-hydroxyacetophenone (2'HAP) exhibited the best overall performance, with a stepped sorption isotherm indicating cooperative absorption and a CO2:MPZ stoichiometry of up to 0.93 at moderate pressures (&#x223c;163 kPa) without the addition of water. While other structurally related additives, including acetophenone (AP), 2'-methoxyacetophenone (2'MAP), and 1,4-diisopropylbenzene (DIPB), also enabled high uptake capacities (absorbed CO2:MPZ stoichiometries up to &#x223c;0.85), the stepped behavior enables enhanced working capacity with reduced temperature differentials, offering potential energy savings in temperature-swing absorption processes. Measurements of performance with different additives including acetophenone isomers and phenolic analogs revealed that CO2 uptake and isotherm shape are governed by solvent acidity, carbonyl presence, and the ability to stabilize carbamic acid intermediates, perhaps through hydrophobic interactions. Equilibrium network modeling supported the proposed mechanism, illustrating how additive-amine interactions shift key equilibria to enable stepped isotherm behavior. Control experiments with monoethanolamine (MEA) and morpholine (MP) underscored the importance of the diamine nature of MPZ in facilitating cooperative uptake. Breakthrough experiments confirmed the system's robust performance across varying CO2 concentrations (4.5-25%). This work provides mechanistic insights into additive-amine cooperativity and highlights MPZ-based nonaqueous systems as promising candidates for energy-efficient CO2 capture.

The development of molecular materials that combine spin-crossover (SCO) and metal-to-metal electron transfer (MMET) in a single system remains a fundamental challenge due to their strongly coupled nature and ultrashort-lived intermediate states. Here we present a series of cyanide-bridged {W6Co9} clusters, [Co@{W(CN)8}6{Co(L)}6{Co(H2O)x(MeOH)3-x}2]&#xb7;sol {L = 2,2,2-tris(1H-pyrazolyl)ethanol, x = 3, sol = MeOH (1) and EtOH (3); L = 1,1',1&#x2033;-(2-(allyloxy)ethane-1,1,1-triyl)tris(1H-pyrazole), x = 2, sol = 4H2O (2)}, that exhibit unprecedented coexistence of reversible SCO, MMET, and photoinduced slow magnetic relaxation. By strategically modulating ligand fields and supramolecular packing, we achieve distinct switching behaviors: one-step incomplete transitions in elastically frustrated triangular-packed systems (1 and 3) and a two-step complete transition in a nonfrustrated grid-like system (2). Remarkably, the frustrated systems exhibit "spin-state-ice-like" behavior, with each triangular unit adopting either a two high-spin/one low-spin (2HS/1LS) or 1HS/2LS configuration, representing the first experimental observation of such behavior in molecular clusters. These findings establish a new paradigm for designing multistable magnetic materials with coupled electronic and spin transitions, offering insights into the interplay between elastic frustration and cooperative spin-state switching.

Advances in genomics, proteomics, and bioinformatics have uncovered the existence of thousands of translated small open reading frames less than 100-150 codons in length that encode microproteins. In addition to their diminutive size, microproteins are also often predicted to be intrinsically disordered based on their enrichment in disordered-promoting amino acids. Microproteins have since been found to regulate diverse cellular processes, including DNA repair, mRNA decay, mitochondrial metabolism, and ribosome biogenesis, among others. While only a small fraction of microproteins have been functionally characterized, many examples have been found to act as regulators of larger proteins and protein complexes in ways similar to annotated intrinsically disordered proteins (IDPs). In this review, we summarize the functions and mechanisms of several disordered microproteins while exploring the approaches used to study their disordered nature, their regulation by post-translational modifications, and potential strategies to therapeutically target them in disease. These examples underscore how investigations of disordered microproteins deepen our understanding of how biological processes are regulated and emphasize how close collaboration between the microprotein and IDP fields can enhance these efforts.