Regulation Of Enzyme Activity Research Articles

Assessing biochar's impact on greenhouse gas emissions, microbial biomass, and enzyme activities in agricultural soils through meta-analysis and machine learning.

The role of biochar in reducing greenhouse gas (GHG) emissions and improving soil health is a topic of extensive research, yet its effects remain debated. Conflicting evidence exists regarding biochar's impact on soil microbial-mediated emissions with respect to different GHGs. This study systematically examines these divergent perspectives, aiming to investigate biochar's influence on GHG emissions and soil health in agricultural soils. The meta-analysis includes 2594 paired observations from 157 studies conducted between 2000 and 2024. It was found that biochar increased the presence of amoA and nosZ genes by 39.4% and 41.7%, respectively, while reducing the abundance of the nirS gene by 17.8%. This led to a 13.1% decrease in N2O emissions. Nitrous emissions were positively associated with mean annual temperature and biochar's pyrolysis temperature and dosage while inversely related to soil pH, nitrogen fertilisation rate, and biochar pH and carbon content. Biochar also regulated enzyme activity related to the nutrient cycle and increased microbial biomass carbon, nitrogen, and phosphorus by 16.6%, 23.9%, and 50.2%, respectively, leading to changes in microbial community diversity. These changes contributed to a reduction in CO2 and CH4 emissions, particularly when biochar and nitrogen fertiliser were applied at doses below 21.4tha-1 and 242.5kgha-1, as predicted by machine learning models. This study offers an overview of the positive impact of biochar amendments on soil GHG emissions mitigation. The key predictive factors identified could help optimise biochar production and targeted amendments, potentially improving soil health and achieving carbon neutrality in agroecosystems.

Effects of periodontal disease on the proteomic profile of the periodontal ligament.

Periodontal disease affects over 1 billion people globally. This study investigated how periodontitis affects the protein profile of the periodontal ligament (PDL) in rats. Eight Holtzman rats were divided into the control and experimental periodontitis groups. The PDL was isolated using laser capture microdissection, and protein extracts were analyzed by mass spectrometry. Data analysis utilized specialized software, and Gene Ontology enrichment analysis identified significant protein functions. The data are available via ProteomeXchange with identifier PXD055817. Proteins such as SerpinB1, C5, and Lgals3 were validated through immunohistochemistry, and their gene expression was examined in an in vitro human PDL cell line. This study identified 1326 proteins, with 156 unique to the control group, 294 unique to the periodontitis group, and 876 common to both groups. Enrichment analysis revealed that proteins associated with the regulation of enzyme activity and RNA binding were significantly represented in the periodontitis group. There were increased levels of SerpinB1, C5, and Lgals3 in the periodontitis group based on proteomic and immunohistochemical analyses. Furthermore, these targets showed increased gene expression in stimulated human PDL cells. This study provides insights into the periodontitis-related alterations in the protein composition of the PDL and PDL cells, identifying both novel and previously known disease-associated proteins. SIGNIFICANCE: The periodontal ligament plays a crucial role in oral functions by providing structural support to the tooth. Due to the presence of undifferentiated mesenchymal cells, research into its regenerative capacity is ongoing. Pathological conditions can affect these functions and protein composition. Currently, there is a lack of comprehensive research specifically focusing on evaluating the periodontal ligament in both healthy and diseased states. This pioneering study screened for protein alterations and the mechanisms related to periodontitis. The possibility of using proteomic analysis to evaluate the protein alterations that occur in periodontitis-a disease with a high global incidence-could provide therapeutic targets and new biomarkers for future clinical studies.

Regulation of endogenous enzyme activity and quality of dry-cured pork loin at ripening stage by electrical stimulation

Regulation of endogenous enzyme activity and quality of dry-cured pork loin at ripening stage by electrical stimulation

Role of Micronutrients in Preventing Chronic Diseases: A Review

Micronutrients, including vitamins and minerals, are essential nutrients required in small quantities but play a critical role in the prevention and management of chronic diseases. These nutrients are integral to various physiological processes, such as immune function, antioxidant defense, enzyme activity, and gene regulation. Deficiencies in key micronutrients, such as Vitamin D, iron, zinc, and folate, have been linked to increased risks of cardiovascular diseases, diabetes, neurodegenerative disorders, and cancer. Recent research highlights the synergistic effects of micronutrients, where combined nutrient intake enhances bioavailability and effectiveness, emphasizing the need for diverse dietary patterns like the Mediterranean diet. Advances in nutrigenomics and personalized nutrition have shown promise in tailoring dietary interventions based on individual genetic profiles, optimizing the preventive impact of micronutrients. The development of functional foods and biofortification of crops presents sustainable solutions to combat micronutrient deficiencies in resource-limited populations. Emerging trends in supplementation, such as high-dose Vitamin C in cancer therapy and magnesium in managing metabolic syndrome, indicate potential therapeutic roles for micronutrients beyond basic nutrition. However, challenges remain, particularly in assessing nutrient bioavailability and addressing confounding factors in epidemiological studies. Ethical considerations in clinical trials and the limitations of current research methodologies call for more comprehensive, long-term studies to better understand the complex interactions between micronutrients and chronic disease prevention. Sustainable agricultural practices and policies focused on enhancing the micronutrient content of foods are important for addressing global nutrition challenges. As research progresses, leveraging new technologies for more accurate nutrient assessment and targeted interventions will be essential in reducing the global burden of chronic diseases. By integrating scientific advancements with public health strategies, there is potential to improve population health outcomes through optimized micronutrient intake. This comprehensive approach highlights the importance of focusing on both individual dietary interventions and broader food system changes to effectively harness the benefits of micronutrients in chronic disease prevention and management.

Curcumin and Its Potential to Target the Glycolytic Behavior of Lactate-Acclimated Prostate Carcinoma Cells with Docetaxel.

Background: Dysregulated cellular metabolism is known to be associated with drug resistance in cancer treatment. Methods: In this study, we investigated the impact of cellular adaptation to lactic acidosis on intracellular energy metabolism and sensitivity to docetaxel in prostate carcinoma (PC) cells. The effects of curcumin and the role of hexokinase 2 (HK2) in this process were also examined. Results: PC-3AcT and DU145AcT cells that preadapted to lactic acid displayed increased growth behavior, increased dependence on glycolysis, and reduced sensitivity to docetaxel compared to parental PC-3 and DU145 cells. Molecular analyses revealed activation of the c-Raf/MEK/ERK pathway, upregulation of cyclin D1, cyclin B1, and p-cdc2Thr161, and increased levels and activities of key regulatory enzymes in glycolysis, including HK2, in lactate-acclimated cells. HK2 knockdown resulted in decreased cell growth and glycolytic activity, decreased levels of complexes I-V in the mitochondrial electron transport chain, loss of mitochondrial membrane potential, and depletion of intracellular ATP, ultimately leading to cell death. In a xenograft animal model, curcumin combined with docetaxel reduced tumor size and weight, induced downregulation of glycolytic enzymes, and stimulated the upregulation of apoptotic and necroptotic proteins. This was consistent with the in vitro results from 2D monolayer and 3D spheroid cultures, suggesting that the efficacy of curcumin is not affected by docetaxel. Conclusions: Overall, our findings suggest that metabolic plasticity through enhanced glycolysis observed in lactate-acclimated PC cells may be one of the underlying causes of docetaxel resistance, and targeting glycolysis by curcumin may provide potential for drug development that could improve treatment outcomes in PC patients.

Analysis of kallikrein-related peptidase 7 (KLK7) autolysis reveals novel protease and cytokine substrates.

Kallikrein-related peptidase 7 (KLK7) is one of 15 members of the tissue kallikrein family and is primarily expressed in the skin epidermis. The activity of KLK7 is tightly regulated by multiple stages of maturation and reversible inhibition, similar to several other extracellular proteases. In this work, we used protease-specific inhibitors and active sitevariants to show that KLK7 undergoes autolysis at two separate sites in the 170 and 99 loops (chymotrypsinogen numbering), resulting in a loss of enzymatic activity. A protein BLAST search using the autolyzed KLK7 loop sequences identified mast cell chymase as a potential KLK7 substrate. Indeed, KLK7 cleaves chymase resulting in a concomitant loss of activity. We further demonstrate that KLK7 can hydrolyze other mast cell proteases as well as several cytokines. These cytokines belong mainly to the interferon and IL-10 families including IFN-α, IFN-β, IFN-γ, IL-28A/IFN-λ2, IL-20, IL-22, and IL-27. This is the first study to identify a possible molecular interaction link between KLK7 and mast cell proteases and cytokines. Although the precise biological implications of these findings are unclear, this study extends our understanding of the delicate balance of proteolytic regulation of enzyme activity that maintains physiological homeostasis, and facilitates further biological investigations.

How Do DNA Molecular Springs Modulate Protein-Protein Interactions: Experimental and Theoretical Results.

Deoxyribonucleic acid (DNA) nanomachines have been widely exploited in enzyme activity regulation, protein crystallization, protein assembly, and control of the protein-protein interaction (PPI). Yet, the fundamental biophysical framework of DNA nanomachines in the case of regulating protein-protein interactions remains elusive. Here, we established a DNA nanospring-mCherry model with mCherry homodimers of different Kd. Using size exclusion chromatography and fluorescence polarization, we profiled the DNA nanospring-mediated manipulation of PPI as an entropy-reducing process. The energy transfer efficiency was a function of the length of the complementary sequence and the geometry of the DNA nanospring construction. With basic force analysis and physical chemistry calculation, we proposed a unified model of the correlation between the dissociation constant, local concentration, construction of DNA nanospring, and kinetics of protein dimerization. Overall, we demonstrated that the DNA nanospring-mCherry conjugate was a simple and practical model to analyze DNA-controlled protein-protein interaction.

Exogenous silicon improved the cell wall stability by activating non-structural carbohydrates and structural carbohydrates metabolism in salt and drought stressed Glycyrrhiza uralensis stem.

The plant cell wall is a crucial barrier against environmental stress, mainly composed of lignin and carbohydrates such as cellulose, hemicellulose, and pectin. This study explored the direct regulatory mechanism of silicon (Si) on cell wall components of Glycyrrhiza uralensis (G. uralensis) stems under salt and drought (S+D) stress and the indirect regulatory mechanism of non-structural carbohydrates on structural carbohydrates, mediated by uridine diphosphate glucose (UDPG), through joint physiological, biochemical, and transcriptomic analyses. Under S+D stress, Si increased the contents of cell wall components, altered the structure of cell wall, and directly promoted cell wall re-construction by regulating gene expression levels and enzyme activities related to cell wall biosynthesis. Meanwhile, Si facilitated the accumulation of carbohydrates by regulating enzyme activities and gene expression levels in the anabolic pathway of polysaccharides, thereby promoting UDPG conversion and indirectly providing substrates for cell wall synthesis. In conclusion, Si directly and indirectly facilitates the synthesis of cell wall components by regulating both cell wall metabolism and non-structural carbohydrates metabolism, thus reinforcing the cell wall, enhancing its stability, and improving the salt and drought tolerance of G. uralensis stems.

Synergistic Effects of Chitosan and Fish Oil on Lipid Metabolism in Rats Fed a High-Fat and Low-Carbohydrate Diet.

Although high-fat, low-carbohydrate diets are used for weight loss and type 2 diabetes management, their high-fat content may have negative effects. This study examines the effects of replacing cellulose with chitosan and part of the fat with fish oil in a high-fat, low-carbohydrate diet on lipid metabolism in rats. The experiment involved 35 six-week-old male SD rats, divided into five groups: normal control diet (ND), high-fat diet (HF), high-fat, low-carbohydrate diet (LC), LC with 5% chitosan (LC-CH), and LC with 5% chitosan and 5% fish oil (LC-CHF). After 15 weeks, the HF group had the highest liver weight, and the LC group had the highest adipose tissue weight. The LC-CHF group showed significantly reduced body, liver, and adipose tissue weights, lower ALT, AST, TNF-α, and cholesterol levels, as well as improved liver enzyme activity and fat synthesis regulation. LC-CHF also promoted fat breakdown in adipose tissue, reducing adipocyte size. Our findings suggest the modified high-fat, low-carbohydrate diet with chitosan and fish oil improved obesity and fatty liver outcomes compared to a standard high-fat diet.

Tailored Metal–Organic Framework‐Based Nanozymes for Enhanced Enzyme‐Like Catalysis

AbstractThe global crisis of bacterial infections is exacerbated by the escalating threat of microbial antibiotic resistance. Nanozymes promise to provide ingenious solutions. Here, we reported a homogeneous catalytic structure of Pt nanoclusters with finely tuned metal–organic framework (ZIF‐8) channel structures for the treatment of infected wounds. Catalytic site normalization showed that the active site of the Pt aggregates structure with fine‐tuned pore modifications structure had a catalytic capacity of 14.903×105 min−1, which was 18.7 times higher than that of the Pt particles in monodisperse state in ZIF‐8 (0.793×105 min−1). In situ tests revealed that the change from homocleavage to heterocleavage of hydrogen peroxide at the interface of the nanozyme was one of the key reasons for the improvement of nanozyme activity. Density‐functional theory and kinetic simulations of the reaction interface jointly determine the role of the catalytic center and the substrate channel together. Metabolomics analysis showed that the developed nanozyme, working in conjunction with reactive oxygen species, could effectively block energy metabolic pathways within bacteria, leading to spontaneous apoptosis and bacterial rupture. This pioneering study elucidates new ideas for the regulation of artificial enzyme activity and provides new perspectives for the development of efficient antibiotic substitutes.

Tailored Metal-Organic Framework-Based Nanozymes for Enhanced Enzyme-Like Catalysis.

The global crisis of bacterial infections is exacerbated by the escalating threat of microbial antibiotic resistance. Nanozymes promise to provide ingenious solutions. Here, we reported a homogeneous catalytic structure of Pt nanoclusters with finely tuned metal-organic framework (ZIF-8) channel structures for the treatment of infected wounds. Catalytic site normalization showed that the active site of the Pt aggregates structure with fine-tuned pore modifications structure had a catalytic capacity of 14.903×105 min-1, which was 18.7 times higher than that of the Pt particles in monodisperse state in ZIF-8 (0.793×105 min-1). In situ tests revealed that the change from homocleavage to heterocleavage of hydrogen peroxide at the interface of the nanozyme was one of the key reasons for the improvement of nanozyme activity. Density-functional theory and kinetic simulations of the reaction interface jointly determine the role of the catalytic center and the substrate channel together. Metabolomics analysis showed that the developed nanozyme, working in conjunction with reactive oxygen species, could effectively block energy metabolic pathways within bacteria, leading to spontaneous apoptosis and bacterial rupture. This pioneering study elucidates new ideas for the regulation of artificial enzyme activity and provides new perspectives for the development of efficient antibiotic substitutes.

Enhanced antioxidant activity of selenium-enriched brown rice protein against oxidative stress in mammalian erythrocytes under various cooking conditions

This study investigated the effects of Selenium-enriched brown rice protein on oxidative stress in the mammalian erythrocytes. Selenium-enriched brown rice protein and native rice protein (control) were treated with mice erythrocytes at various cooking processes. The research explored the antioxidant activity of enzymes, including superoxide dismutase (SOD), catalase CAT), and lipid peroxidase (LPO) as well as markers of oxidative damage such as malondialdehyde (MDA). Furthermore, the investigation analyzed the expression of proteins, including nuclear factor erythroid 2-related factor 2 (Nrf2), a principal regulator of the antioxidant response, and Band3, a membrane protein crucial for erythrocyte function. The study also examined the influence of different types of cooking on the effectiveness of selenium-enriched brown rice protein and native rice protein (control). Cooking increased the protection against oxidative damage of red blood cells; high-pressure cooking demonstrated the highest efficacy, followed by microwave cooking and low-pressure cooking. In addition, the results indicated that this protection mechanism might be related to the regulation of antioxidant enzyme activities and gene expressions induced by Peroxiredoxins (PRP) protein, Band3, and Nrf2 genes, leading to decreased lipid peroxidation and oxidative product generation. This contributed to the preservation of RBC integrity and decreased the rate at which it was Hemolysis. Our findings suggest that the protective mechanism of PRP against oxidative damage in RBCs is associated with the regulation of PRP, Band3 protein, and Nrf2 gene expression. This regulation reduces lipid peroxidation, minimizes LPO and MDA production, and preserves cell integrity, ultimately decreasing the hemolysis rate under oxidative stress.

Predicting the therapeutic role and potential mechanisms of Indole-3-acetic acid in diminished ovarian reserve based on network pharmacology and molecular docking

BackgroundIndole-3-acetic acid (IAA), an indole analog produced by intestinal microorganisms metabolizing tryptophan, has anti-inflammatory and antioxidant properties and thus has potential applications in ovarian protection, although the exact mechanism is unknown. The present study preliminarily investigated the pharmacological mechanism of IAA in alleviating diminished ovarian reserve (DOR) by network pharmacology and molecular docking.MethodsRelevant target proteins of IAA were searched in SwissTargetPrediction, PharmMapper, TargetNet, BATMAN-TCM, and SuperPred databases. The potential targets of DOR were obtained from GeneCards, DisGenet, OMIM, and Drugbank databases. Both common targets were then imported into the String website to construct a PPI network, and these targets were analyzed for GO and KEGG enrichment. Finally, we utilized molecular docking to validate the possible binding conformations between IAA and the candidate targets. We used in vitro experiments to preliminarily investigate the effects of IAA on DOR.ResultsWe obtained 88 potential targets for IAA and DOR interaction. We received 16 pivotal targets by constructed protein interaction screening. KEGG enrichment analysis mainly included the AGE-RAGE signaling pathway, IL-17 signaling pathway, Chemical carcinogenesis—reactive oxygen species in diabetic complications, etc. GO functional analysis showed that IAA treatment of DOR may involve biological processes such as response to external stimuli, hypoxia, gene expression, and regulation of enzyme activity. Molecular docking and in vitro experiments further revealed the potential effects of IAA on MMP2, TNF-α, AKT1, HSP90AA1, and NF-κ B.ConclusionWe preliminarily revealed the potential protective effects of IAA against DOR through multiple targets and pathways, which provides a new research strategy for the molecular mechanism of IAA to alleviate DOR in the future. However, further studies need to demonstrate whether IAA can be used as a compound to prevent and treat DOR.

The effects of dexmedetomidine on thiol/disulphide homeostasis in coronary artery bypass surgery: a randomized controlled trial

BackgroundThiol-disulfide homeostasis (TDH) plays a pivotal role in various physiological mechanisms, including antioxidant defence, detoxification, apoptosis, regulation of enzyme activities and cellular signal transduction. TDH can be used as a biomarker to detect oxidative stress (OS) levels and ischemia status in the tissues. Coronary artery bypass grafting (CABG) surgery is a procedure associated with high oxidative stress. Dexmedetomidine, an alpha-2 agonist anaesthetic agent, has antioxidant effects. In this study, the effects of dexmedetomidine on oxidative stress in CABG surgery were investigated.MethodsPatients who underwent on-pump CABG surgery were divided into two groups: those receiving dexmedetomidine (Group D) and those not receiving dexmedetomidine (Group C). From anesthesia induction to the end of surgery, patients in Group D received intravenous infusions of 0.05–0.2 mcg/kg/min remifentanil and 0.2–0.7 mcg/kg/h dexmedetomidine. Patients in Group C received intravenous infusion of 0.05–0.2 mcg/kg/min remifentanil. Blood samples were collected from the patients 30 min before induction of anesthesia (T1), 30 min after removal of the aortic cross-clamp (T2), and at the end of the surgery (T3). Thiol-disulfide homeostasis (TDH) was assessed using a novel method. A novel automated method enables the determination of native thiols, total thiols and disulfides levels in plasma, allowing the calculation of their respective ratios.ResultsIn patients receiving dexmedetomidine, lower postoperative levels of disulfide, disulfide/native thiol, and disulfide/total thiol, along with higher native thiol/total thiol, were observed compared to the control group. (p < 0.05) Postoperative native thiol and total thiol levels were similar for both groups. (p > 0.05)ConclusionsIn our study, through dynamic thiol-disulfide measurements, we found that levels of oxidative stress (OS) were lower in patients who received dexmedetomidine. We believe that the positive effects of dexmedetomidine on OS could be beneficial in CABG surgery. Furthermore, we anticipate that with further studies conducted in larger patient cohorts, the clinical utilization of dexmedetomidine will become more widespread.Trial registration numberNCT05895331 / 06.07.2023.

Oxidative stress levels and antioxidant defense mechanisms (Nrf2-Keap1 signaling pathway) in the Harderian glands of hibernating Daurian ground squirrels

Cyclic hibernation bouts in Daurian ground squirrels (Spermophilus dauricus) lead to repeated suppression and recovery of mitochondrial respiratory function across multiple organs, potentially impacting reactive oxygen species (ROS) dynamics. The Harderian gland (HG) plays an important role in endocrine regulation through porphyrin secretion. However, the influence of hibernation on oxidative pressure and associated antioxidant pathways in the HG remains inadequately understood. In the current study, we investigated the morphological changes, secretory activity, ROS levels, and underlying mechanisms in the HG of Daurian ground squirrels at distinct circannual stages of hibernation. Results indicated that: (1) Protoporphyrin levels in the HG increased during hibernation compared to the summer active (SA) phase, with a reduction in acinar lumen during torpor, potentially related to hibernation in a low-light environment. (2) Hydrogen peroxide (H2O2) and malondialdehyde (MDA) content during hibernation and post-hibernation (POST) did not exceed the levels observed in SA, indicating that the HG effectively mitigated oxidative pressure and lipid peroxidation during these periods. (3) Superoxide dismutase (SOD) activity increased while glutathione peroxidase (GPx) activity decreased during Inter-bout arousal (IBA) compared to both SA and torpor, although total antioxidant capacity (T-AOC) remained stable across all stages. (4) Overall fluorescent intensity of nuclear factor erythroid 2-related factor 2 (Nrf2) and Kelch-like ECH-associated protein 1 (Keap1) was significantly lower than in SA. These findings demonstrate that the HG in Daurian ground squirrels maintains a favorable oxidative status through the regulation of antioxidant enzyme activities during hibernation and even post-hibernation.

Substrate specificity and kinetic mechanism of 3β-hydroxy-[formula omitted]5-C27-steroid oxidoreductase

Cholesterol is a key sterol whose homeostasis is primarily maintained through bile acid metabolism. Proper bile acid formation is vital for nutrient and fat-soluble vitamin absorption and emulsification of lipids. Synthesis of bile acids occurs through two main pathways, both of which rely on 3-hydroxy-5-C27 steroid oxidoreductase (HSD3B7) to begin epimerization of the 3β hydroxyl of cholesterol into its active 3α conformation. In this sequence HSD3B7 catalyzes the dehydrogenation of the 3β-hydroxy group followed by isomerization of the Δ5-cholestene-3-one. These reactions are some of the many steps that transform cholesterol for either storage or secretion. HSD3B7 has distinct activity from other 3β-HSD family members leaving significant gaps in our understanding of its mode of catalysis and substrate specificity. Additionally, the role of HSD3B7 in health and disease positions it as a metabolic vulnerability that could be harnessed as a therapeutic target. To this end, we evaluated the mechanism of HSD3B7 catalysis and reveal that HSD3B7 displays activity towards diverse 7α-hydroxylated oxysterols. HSD3B7 retains its catalytic efficiency towards these substrates, suggesting that its substrate binding pocket can withstand changes in polarity upon alterations to this hydrocarbon tail. Experiments aimed at determining substrate order are consistent with HSD3B7 catalyzing a sequential ordered bi bi reaction mechanism with the binding of NAD+ followed by 7α-hydroxycholesterol to form a central complex. HSD3B7 bifunctional activity is dependent on membrane localization through a putative membrane-associated helix giving insight into potential regulation of enzyme activity. We found strong binding of the NADH product thought to activate the isomerization reaction. Homology models of HSD3B7 reveal a potential substrate pocket that allows for oxysterol binding and mutagenesis was utilized to support this model. Together these studies offer an understanding of substrate specificity and kinetic mechanism of HSD3B7 which can be exploited for future drug development.

Postharvest application of sodium nitroprusside improves the quality of ‘Umran’ ber fruit under cold storage conditions by regulating enzyme activities

ABSTRACT Ber fruit is highly perishable, with a storage life of only 3–5 days under ambient conditions, which makes it difficult to transport the fruit even to domestic markets. An experiment was conducted to study the effect of postharvest treatment with sodium nitroprusside (50, 100 and 150 µM) on the storage life, quality attributes, bioactive composition and antioxidant enzyme contents of ‘Umran’ ber fruit. The treated fruit were stored for 28 days to investigate the effects of sodium nitroprusside after 7 days of cold storage at 7.5°C and 90–95% RH. It was found that fruit treated with 100 μM sodium nitroprusside experienced lower fruit weight loss and spoilage, maintained fruit firmness, and had a higher sensory quality, phenolic content, carotenoid content, soluble solids content, sugar content, ascorbic acid and antioxidant activity than the control. Furthermore, the activities of the cell wall degrading enzymes polygalacturonase, polyphenol oxidase, pectin methyl esterase and catalase were lower, while the activities of superoxide dismutase and peroxidase enzymes were higher in the treated fruit. Therefore, treatment with 100 μM sodium nitroprusside shows high potential for improving the storage life and maintaining the quality attributes of ber fruit for up to 21 days under cold storage.

Radical-Scavenging Violet Phosphorus Nanosheets for Attenuating Hyperinflammation and Promoting Infected Wound Healing.

Antibacterial therapy targeting the regulation of macrophage polarization may be a useful approach for normalizing the immune environment and accelerating wound healing. Inspired by black phosphorus-based nanoplatforms, more stable yet less-explored violet phosphorus nanosheets (VPNSs) are expected to provide a superior solution for effectively combating bacterial infections. In this study, an average thickness of 5-7nm VPNSs arefabricated through the liquid-phase exfoliation method to serve as an immunoregulatory dressing for the treatment of infected wounds. VPNSs attenuated excessive reactive oxygen species (ROS) and reduced the accumulation of proinflammatory M1 macrophages, showing notable antioxidant and anti-inflammatory properties. Comprehensive RNA sequencing further elucidated the potential immunoregulatory mechanisms of VPNSs, including modulation of the inflammatory response and enzyme regulator activity. Additionally, the inherent photothermal properties of the VPNSs contributed significantly to their antibacterial efficacy. When combined with near-infrared laser irradiation, VPNSs showed remarkable effectiveness in reducing infection-related complications and expediting wound healing in infected skin wound models. The rapid promotion of wound healing through ROS clearance, the regulation of macrophage polarization, and hyperthermia generation underscores the potential of the violet-phosphorus-based nanoplatforms as clinically viable agents for treating infected wounds. This study suggests that VPNSs are promising candidates for clinical anti-infective and anti-inflammatory applications.

High-Efficiency Enzyme Assay and Screening of Enzyme-Inhibiting Nanomaterials Using Capillary Electrophoresis with Hierarchically Porous Metal-Organic Framework-Based Immobilized Enzyme Microreactor.

Enzyme-inhibiting nanomaterials have significant potential for regulating enzyme activity. However, a universal and efficient method for systematically screening and evaluating the inhibitory effects of various nanomaterials on drug target enzymes has not been established. While the integrated technique of immobilized enzyme microreactor (IMER) with capillary electrophoresis (CE) serves as an effective tool for enzyme analysis, it still faces challenges such as low enzyme loadability, unsatisfactory stability, and limited applicability. Herein, hierarchical porous metal-organic frameworks (HP-MOFs) were explored as high-performance enzyme immobilization carriers and stationary phases to develop a novel HP-MOFs-based IMER-CE microanalysis system for efficient online enzyme assay and systematic screening of enzyme-inhibiting nanomaterials. As a proof-of-concept demonstration, the model enzyme xanthine oxidase (XOD) was immobilized on a HP-UiO-66-NH2 coated capillary, serving as an efficient and durable IMER for screening potential XOD-inhibiting nanomaterials. The hierarchically micro- and mesoporous structure and superior enzyme loadability of as-prepared HP-UiO-66-NH2-IMER was intensively characterized, followed by systematic evaluation of the separation performance of HP-UiO-66-NH2 coated column and the enzyme kinetics of the immobilized XOD. Compared to the microporous UiO-66-NH2-IMER, the HP-UiO-66-NH2-IMER-CE system showed significant improvements in enzyme loading, maximum reaction rate, repeatability, and long-term stability. Furthermore, the established method was effectively employed to screen the XOD inhibitory activity of various nanomaterials, revealing that graphene oxide, single wall carbon nanotube and three other nanomaterials exhibited inhibitory potentials. The HP-MOFs-based microanalysis system can be easily expanded by modifying the types of immobilized enzymes and holds the potential to accelerate the identification and rational design of effective enzyme-inhibiting nanomaterials.

Functions and mechanisms of non-histone protein acetylation in plants.

Lysine acetylation, an evolutionarily conserved post-translational protein modification, is reversibly catalyzed by lysine acetyltransferases and lysine deacetylases. Lysine acetylation, which was first discovered on histones, mainly functions to configure the structure of chromatin and regulate gene transcriptional activity. Over the past decade, with advances in high-resolution mass spectrometry, a vast and growing number of non-histone proteins modified by acetylation in various plant species have been identified. Lysine acetylation of non-histone proteins is widely involved in regulating biological processes in plants such as photosynthesis, energy metabolism, hormone signal transduction and stress responses. Moreover, in plants, lysine acetylation plays crucial roles in regulating enzyme activity, protein stability, protein interaction and subcellular localization. This review summarizes recent progress in our understanding of the biological functions and mechanisms of non-histone protein acetylation in plants. Research prospects in this field are also noted.