We used a litterbag method to investigate litter decomposition and related soil degradative enzyme activities across four seasons in a broad-leaved forest and a coniferous forest on Zijin Mountain in sub-tropical Chin...We used a litterbag method to investigate litter decomposition and related soil degradative enzyme activities across four seasons in a broad-leaved forest and a coniferous forest on Zijin Mountain in sub-tropical China. Across four seasons, we quantified litter mass losses, soil pH values, and related soil degradative enzyme activities. Litter decomposition rates differed significantly by season. Litter decomposi- tion rates of broadleaf forest leaves were higher than for coniferous for- ests needles across four seasons, and maximal differences in litter de- composition rates between the two litter types were found in spring.展开更多
Rhizospheres can promote self-transmissible plasmid transfer,however,the corresponding mechanism has not received much attention.Plant-microbe remediation is an effective way to promote pollutant biodegradation;howeve...Rhizospheres can promote self-transmissible plasmid transfer,however,the corresponding mechanism has not received much attention.Plant-microbe remediation is an effective way to promote pollutant biodegradation;however,some pollutants,such as naphthalene,are harmful to plants and result in inefficient plant-microbe remediation.In this study,trans-fer of a TOL-like plasmid,a self-transmissible plasmid loaded with genetic determinants for pollutant degradation,among different bacteria was examined in bulk and rhizosphere soils as well as addition of maize root exudate and its artificial root exudate(ARE).The results showed that the numbers of transconjugants and recipients as well as bacterial metabolic activities,such as xylE mRNA expression levels and catechol 2,3-dioxygenase(C23O)activ-ities of bacteria,remained high in rhizosphere soils,when compared with bulk soils.The number of transconjugants and bacterial metabolic activities increased with the increasing exudate and ARE concentrations,whereas the populations of donor and recipient bacteria were substantially unaltered at all concentrations.All the experiments consistently showed that a certain number of bacteria is required for self-transmissible plasmid transfer,and that the increased plasmid transfer might predominantly be owing to bacterial metabolic activ-ity stimulated by root exudates and ARE.Furthermore,ARE addition increased naphthalene degradation by transconjugants in both culture medium and soil.Thus,the combined action of a wide variety of components in ARE might contribute to the increased plasmid transfer and naphthalene degradation.These findings suggest that ARE could be an effectively al-ternative for plant-microbe remediation of pollutants in environments where plants cannot survive.展开更多
Fungi are the key agents in litter decomposition in forest ecosystems. However, the specific roles of the interactions between different fungal species during litter decomposition process are unclear. To evaluate the ...Fungi are the key agents in litter decomposition in forest ecosystems. However, the specific roles of the interactions between different fungal species during litter decomposition process are unclear. To evaluate the interactions, two fungi strains with significantly different morphs were isolated from the soils of Quercus acutissima forest and Pinus massoniana forest, and inoculated in the litter powder of Quercus acutissima leaves and Pinus massoniana needles with grown separately and in coexistence equally through a microcosm experiment. The enzyme activities were determined as a proxy for microbial activities. The results showed that the degradative enzymes involved in litter decomposition showed varying dynamics pattern during the incubation period. The interactions between the two fungi strains are synergism, and benefit to each other according to enzyme activities, suggesting that a fungi strain growth was accelerated by the presence of other fungi strain during litter decomposition process. However, the interactions of the two fungi strains were bilateral antagonism inoculated in the litter powder of Quercus acutissima leaves according to cellobiohydrolase activities. The synergism, despite bilateral antagonism in an exceptional case, may be an important factor controlling the fungal colonization and growth on litter substrate. The results implied that more fungal species may accelerate litter decomposition rates due to their mutual cooperation.展开更多
We put forward a new approach for the synthesis of Ag@AgCl plasmonic photocatalyst via a hydrothermal-deposition-photoreduction method. The cetylmethylammonium chloride （CTAC） was used alone as both a source of reac...We put forward a new approach for the synthesis of Ag@AgCl plasmonic photocatalyst via a hydrothermal-deposition-photoreduction method. The cetylmethylammonium chloride （CTAC） was used alone as both a source of reactants and surfactant. The structure of the prepared photocatalyst was determined by XRD, SEM, EDX and UV-Vis spectroscoscopy. The photocatalytic properties were investigated by degradation of an organic pollutant, Rhodamine B, under visible light irradiation. The results reveal that the experimental conditions have a great effect on the morphology of Ag@AgCl crystals. Ag@AgC1 crystal is cubic and the Ag@AgCl sample which is photoreduced for 40 min exhibits the highest photoactivity, and 80.6 % RhB is degraded after irradiation for 2 hours using this catalyst. The high photocatalytic activity observed is attributed to the surface plasmon resonance effect ofAg nanoparticles.展开更多
Steviaside containing plant extracts have been used for degradation of persistent chloroorganic pesticides. Reactions between DDT and Steviaside or sum of extractive substances isolated from ground up part of plant St...Steviaside containing plant extracts have been used for degradation of persistent chloroorganic pesticides. Reactions between DDT and Steviaside or sum of extractive substances isolated from ground up part of plant Stevia were studied to give of less toxic DDE. Herein researches on studying interaction sum of polysaccharides of Stevia with DDT in various ratios resulted also. The GC-MS and GLC methods were used for analyzing degradation degree of pesticides and to determine obtained compounds. Treat HCCH by water extract of Stevia basically formed tetrachlorocyclo-hexadiene (HCH) with 86.9% yield and in particularly formed of tri-, tetrachlorobenzenes. The HCH formed in 79.7% on treat pesticide by 80% Steviaside. Degradation of HCCH and DDT by water extract of Stevia in a presence of Ana-basine in a ratio of 2:1:1 occur to degrade of HCCH up to 70-80%, and DDT on 25% - 30%.展开更多
The genetic information encoding metabolic pathways for xenobiotic compounds in bacteria often resides on catabolic plasmids.The aim of the present work was to know the location of the genes for degrading 1,2,4-trichl...The genetic information encoding metabolic pathways for xenobiotic compounds in bacteria often resides on catabolic plasmids.The aim of the present work was to know the location of the genes for degrading 1,2,4-trichlorobenzen.In this paper a 1,2,4-trichlorobenzene-degrading strain THSL-1 was isolated from the soil of Tianjin Chemical Plant using 1,2,4-trichlorobenzene as the sole carbon source.The strain was identified as Pseudomonas stutzeri through morphologic survey and 16S rDNA sequence determination.A plasmid was discovered from strain THSL-1 by using the alkali lysis method.When the plasmid was transformed into E.coli.JM109 by the CaCl2 method,the transformant could grow using 1,2,4-trichlorobenzene as the sole carbon source and had the degradation function of 1,2,4-trichlorobenzene.Therefore,it could be deemed that the plasmid carried the degradative genes of 1,2,4-trichlorobenzene.The average size of the plasmid was finally determined to be 40.2 Kb using selectively three kinds of restricted inscribed enzymes(HindIII,BamHI,and XholI)for single cutting and double cutting the plasmid pTHSL-1,respectively.展开更多
A degradative solvent extraction(DSE)method was proposed to upgrade low-rank coals(LRC)for their cascaded utilizations in a highly-dispersed medium.The derived products exhibited well improved properties in comparison...A degradative solvent extraction(DSE)method was proposed to upgrade low-rank coals(LRC)for their cascaded utilizations in a highly-dispersed medium.The derived products exhibited well improved properties in comparison to the raw LRCs.Previously,the LRCs were pre-dried to eliminate the potential impact of the varied water content of raw LRCs,but in light of the abundant water in fresh coals,the hydrolyzing effect of water on coals under heating,and the energy cost to pre-dry the LRCs,it is consequently essential to clarify the effect of water so as to verify the necessity of pre-drying process.In this study,the roles of inherent water and extra-added water were respectively investigated,using dried,raw and wet coals from two typical LRCs.The results show that increasing the moisture content of raw LRCs contributed to the extraction ability of DSE method without noticeably changing the elemental composition,chemical structure and thermal decomposition behavior of extractable products,thus pre-drying of LRCs before DSE treatment was proven unnecessary.Additionally,the roles of the inherent water were concluded as:1)leading to the formation of stable covalent bond during drying process;and 2)acting as H donor to promote extraction ability,while the added water can only function as H donor.Since excessive water will increase the pressure during DSE treatment and lead to the waste water treatment,the LRCs with a water content between 10%and 30%were consequently recommended for the practical application of DSE treatment.展开更多
The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsor...The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsorption and biological degradation,are often hampered by low efficiency and the risk of secondary pollution.Photocatalysis emerges as a promising sustainable alternative;however,the benchmark material titanium dioxide(TiO_(2))suffers from its intrinsic limitations,notably its wide bandgap energy(≥3.4 eV)restricting its activity to the region of the ultraviolet light and its rapid recombination of photogenerated charge carriers.To overcome these constraints,this research focused on synthesizing novel TiO_(2)/Sn_(3)O_(4) heterojunction composite photocatalysts via a solvothermal approach.Comprehensive characterization techniques confirmed the successful formation of the composite,which revealed that ultrathin Sn3O4 nanosheets uniformly coated TiO_(2) nanospheres.This unique architecture effectively reduced the overall crystallinity and introduced the beneficial oxygen vacancies.Under visible-light irradiation(λ≥420 nm),the optimized TiO_(2)/Sn3O4 composite exhibited the exceptional photocatalytic performance,which achieved 96%degradation of MO within just 60 minutes.The calculated apparent kinetic rate constant(0.103 min^(-1))was remarkably(5.15 times)higher than that of pristine TiO_(2).ESR experiments identified that hydroxyl radicals(·OH)was the predominant active species driving the degradation.Furthermore,cyclic degradation tests demonstrated its excellent material stability,with the composite retaining 85%of its initial efficiency after four consecutive reuse cycles.This work underscored the synergistic effects within the TiO_(2)/Sn_(3)O_(4) heterojunction,which significantly enhanced the visible-light absorption,charge separation,and photocatalytic activity,which provided the valuable insights for designing efficient,stable catalysts for the advanced environmental remediation applications.展开更多
A degradative solvent extraction method for upgrading low-rank coal was performed at 200-350◦C for 90 min to obtain a substance dissolved in the solvent at room temperature(Soluble).Because the resulting mixture exhib...A degradative solvent extraction method for upgrading low-rank coal was performed at 200-350◦C for 90 min to obtain a substance dissolved in the solvent at room temperature(Soluble).Because the resulting mixture exhibited a high carbon content without ash,it could be readily used as a fuel.Furthermore,deep eutectic solvents(DESs)have attracted attention for improving the Soluble yield and decreasing the oxygen content in Soluble.DES is known to cleave oxygen-containing functional groups in biomass and is considered effective for deoxidizing low-rank coal.Herein,DES was prepared by mixing choline chloride,FeCl3⋅6H2O,and Adaro subbituminous coal(AD)and then added to 1-methylnaphthalene(1-MN)in a non-polar solvent,followed by degradative solvent extraction in the range of 200-350◦C.The effects of reaction temperature and added DES amount on the product yield and the composition were evaluated.As the reaction temperature and amount of DES added increased,the Soluble yield and carbon content increased.It was also found that the thermal decomposition temperature and oxygen content decreased with the increasing DES amounts.This decrease indicates that DES promotes the deoxygenation and decomposition of AD and increases the soluble yield of the fuel source.展开更多
The microbial degradation of aromatic organic pollutants is incomplete due to their metabolic characteristics,which can easily produce certain highly toxic intermediates.Therefore,this article designs a dual template ...The microbial degradation of aromatic organic pollutants is incomplete due to their metabolic characteristics,which can easily produce certain highly toxic intermediates.Therefore,this article designs a dual template molec-ularly imprinted sensor(DTMIP/Fe-Mn@C)for iron manganese metal nanomaterials,prepared Fe-Mn@C com-posite materials by a one pot method were coated on the surface of glassy carbon electrodes and covered with molecularly imprinted membranes through electropolymerization and elution methods,achieving real-time de-tection of specific intermediate products 2-methylbutyric acid(2-MBA)and 3-methylbutyric acid(3-MBA)de-graded by azo dyes.In order to determine the detection sensitivity and intensity range of the sensor,optimization experiments were conducted on various parameters that affect the detection performance,such as the type of func-tional monomer and its composition ratio with the template molecule,detection time window,environmental pH value,etc.Finally,o-Phenylenediamine was determined as the functional monomer,with a molar ratio of 1:1:6 to the template molecules 2-MBA and 3-MBA.Electrochemical testing was conducted in a neutral environment with an incubation time of 5 min and pH=7.The results indicate that the sensor has a relatively wide detection range,high sensitivity,obvious recognition features,and excellent stability for 2-MBA and 3-MBA.This new dual template molecularly imprinted sensor can quickly and accurately determine the safety of highly toxic interme-diates in the degradation process of aromatic organic pollutants,providing a theoretical basis and application potential for trace detection and real-time monitoring.展开更多
While nuclear energy represents a low-carbon and high-efficiency energy source that plays a vital role in the global energy mix,the limitations of spent fuel reprocessing technology pose a major challenge to its susta...While nuclear energy represents a low-carbon and high-efficiency energy source that plays a vital role in the global energy mix,the limitations of spent fuel reprocessing technology pose a major challenge to its sustainable development.The PUREX(plutonium uranium redox extraction)process is currently the dominant nuclear fuel reprocessing technology in the world.However,the key extractant in this process is tributyl phosphate(TBP),which degrades under intense radiation,high temperatures,and strong acidity.This leads to the production of dibutyl phosphate,monobutyl phosphate,and other degradation byproducts,which may reduce the extraction efficiency and trigger third-phase formation and equipment corrosion.This paper systematically reviews the degradation mechanisms of TBP and its diluents,the analytical technique suitable for characterizing degradation products,and the impact of degradation products on the post-treatment process.Additionally,optimization strategies employed for suppressing third-phase formation are discussed.This study offers a theoretical foundation and technical insights in optimizing the PUREX process and ensuring the safe operation of the post-treatment process.展开更多
Zearalenone(ZEN),a mycotoxin present in cereals,poses significant health risks to animals and humans due to its estrogenic effects.Numerous studies on the enzymatic detoxification of ZEN have predominantly focused on ...Zearalenone(ZEN),a mycotoxin present in cereals,poses significant health risks to animals and humans due to its estrogenic effects.Numerous studies on the enzymatic detoxification of ZEN have predominantly focused on reducing the parent toxin to assess the enzyme’s efficacy,yet there is limited research on the identification and toxicity evaluation of the enzymatic degradation products.This study investigated the enzymatic degradation mechanisms of ZEN using commercial peroxidase(POD)and laccase(LC),with a focus on identifying degradation products and assessing their hepatotoxicity effects.Molecular docking and dynamics simulations elucidated the binding mechanisms between these enzymes and ZEN,revealing strong interactions that facilitate efficient detoxification.Subsequent analysis employing ultra-high performance liquid chromatography-high resolution mass spectrometry(UHPLC-HRMS)successfully identified crucial degradation products.Hepatic toxicity of the enzymatic degradation products was comprehensively assessed in HepaRG liver cells through systematic measurements of cell viability,oxidative stress,apoptosis,mitochondrial membrane potential,and molecular metabolic profiles.Our findings demonstrate that both POD and LC exhibit significant efficacy in mitigating hepatocyte toxicity induced by ZEN,thereby highlighting their potential utility in enhancing food safety.This research provides essential data for safety evaluation regarding enzymatic detoxification of ZEN while offering theoretical and technical resources for risk assessment related to mycotoxin enzymatic detoxification.展开更多
The escalating global issues of water scarcity and pollution emphasize the critical need for the rapid development of efficient and eco-friendly water treatment technologies.Photoelectrocatalytic technology has emerge...The escalating global issues of water scarcity and pollution emphasize the critical need for the rapid development of efficient and eco-friendly water treatment technologies.Photoelectrocatalytic technology has emerged as a promising solution for effectively degrading refractory organic pollutants in water under light conditions.This review delves into the advancements made in the field,focusing on strategies to enhance the generation of active species by modulating the micro-interface of the photoanode.Strategies,such as morphological control,element doping,introduction of surface oxygen vacancies,and construction of heterostructures,significantly improve the separation efficiency of photogenerated charges and the generation of active species,thereby boosting the efficiency of photoelectrocatalytic performance.Furthermore,the review explores the potential applications of photoelectrocatalytic technology in organic pollutant degradation in solutions.It also outlines the current challenges and future development directions.Despite its remarkable laboratory success,practical implementation of photoelectrocatalytic technology encounters obstacles related to stability,cost-effectiveness,and operational efficiency.Future investigations need to focus on optimizing the performance of photoelectrocatalytic materials and exploring strategies for upscaling their application in real water treatment scenarios.展开更多
Roasting constitutes a critical stage in sesame oil production,where the thermal degradation of pectic polysaccharide initiates fundamental chemical transformations including caramelization,Maillard processes,lipid ox...Roasting constitutes a critical stage in sesame oil production,where the thermal degradation of pectic polysaccharide initiates fundamental chemical transformations including caramelization,Maillard processes,lipid oxidation and Strecker degradation.This study systematically examines the structural,chemical and oil antioxidant capacity of sesame hull-derived pectic polysaccharides(URA and URB)under 160–220℃,and their impacts on sesame oil oxidative stability.The results demonstrate temperature-dependent molecular restructuring of URA and URB with molecular weights increasing proportionally and reduced total yields by 42.73%until 220℃.Furfural and organic acids were identified as primary pyrolysis products,accompanied by volatile aromatic compounds including furans,benzenes,and phenols.Sesame oil with the mixture of URA and URB(HSO-URA/B)exhibited optimal thermal antioxidant performance,demonstrating improved sesame oil oxidative stability as evidenced by peroxide value(0.07–0.81 g/100 g)and oxidative stability index(22.6 h).This work provides a scientific foundation for optimizing sesame oil quality while transforming hull byproducts into valueadded food ingredients.展开更多
This study focuses on a new and high-efficiency approach in a unified sense of accurately simulating strength-degrading effects for geomaterials,including non-symmetric hardening-to-softening effects in tension and co...This study focuses on a new and high-efficiency approach in a unified sense of accurately simulating strength-degrading effects for geomaterials,including non-symmetric hardening-to-softening effects in tension and compression as well as non-symmetric tensile and compressive stiffness-degrading effects during unloading.It is intended to bypass both modeling and numerical complexities involved in existing approaches.To this goal,new elastoplastic equations are established with new numerical techniques.With a decoupling technique of treating tension-compression asymmetry,the foregoing complex effects are automatically incorporated as inherent response features of the new elastoplastic equations,thus bypassing usual modeling complexities.A new numerical technique of renormalizing piecewise spline functions is introduced to resolve the central yet tough issue of obtaining accurate and unified expressions for the tensile and compressive strength functions,thus bypassing usual numerical complexities and uncertainties in treating numerous unknown parameters and multiple ad hoc criteria.As such,the new approach is not only of wide applicability for various geomaterials but also of high computational efficiency with no more than three adjustable parameters.Toward validating the efficacy of the new approach,numerical examples for granite,salt rock,and sandstone-concrete combined body as well as plain concrete,high-performance concrete,and ultrahigh-performance concrete are presented by comparing model predictions with multiple data sets for strength-degrading effects in tension and compression.展开更多
Livestock farming is a critical pillar of Tajikistan’s national economy and livelihood security.However,significant economic challenges in the country have led to the degradation of grassland ecosystems.This degradat...Livestock farming is a critical pillar of Tajikistan’s national economy and livelihood security.However,significant economic challenges in the country have led to the degradation of grassland ecosystems.This degradation has not only reduced the productivity of grassland ecosystems but also severely impacted their ecological functions.A particularly concerning consequence is the threat to biodiversity,as the survival and persistence of endemic,rare,and endangered plant species are at serious risk,thereby diminishing the value of species’genetic resources.Based on the data from multiple sources such as literature reviews,field observations,and national statistics,this study employed a systematic literature review and meta-analysis to investigate the current status,causes of degradation,and restoration measures for grassland ecosystems in Tajikistan.The results revealed that Tajikistan’s grassland ecosystems support exceptionally high plant species diversity,comprising over 4500 vascular plant species,including nearly 1500 endemic and sub-endemic taxa that constitute a unique genetic reservoir.These ecosystems are experiencing severe degradation,characterized by significantly reduced vegetation cover and declining species richness.Palatable forage species are increasingly being displaced by unpalatable,thorny,and poisonous species.The primary drivers of degradation include excessive grazing pressure,which disrupts plant reproductive cycles and regeneration capacity,habitat fragmentation due to urbanization and infrastructure development,and uncontrolled exploitation of medicinal and edible plants.Climate change,particularly rising temperatures and altered precipitation patterns,further exacerbates these anthropogenic pressures.Ecological restoration experiments suggested that both ecosystem productivity and plant species diversity are significantly enhanced by systematic reseeding trials using altitude-adapted native species.These findings underscore the necessity of establishing scientifically grounded approaches for ecological restoration.展开更多
Background Sustainable livestock production is essential for food security and environmental management. Lignocellulosic biomass can be used in animal feed, thereby reducing feed production costs and enhancing sustain...Background Sustainable livestock production is essential for food security and environmental management. Lignocellulosic biomass can be used in animal feed, thereby reducing feed production costs and enhancing sustainability. Expansin-like proteins(ELPs) play essential roles in plant cell wall degradation, yet their functions remain largely underexplored in rumen microbes. The purpose of this study was to investigate the effects of rumen microbial ELPs on lignocellulose degradation.Results This study systematically identified 396 ELPs within the rumen microbiota, uncovering remarkable diversity, particularly among anaerobic fungi. Three representative ELPs from Pecoramyces ruminantium F1(PFLoos_1, PFSWO1_1, PFSWO2_1) were selected for biochemical characterization. While PFSWO2_1 could not be expressed, PFLoos_1 and PFSWO1_1 exhibited significant synergy with cellulases. The CBM10-containing PFSWO1_1 demonstrated superior thermal stability(up to 65 ℃) and substrate affinity, increasing rice straw hydrolysis efficiency by 21.6%(reducing sugar yield) compared to cellulase alone. Structural analyses revealed that CBM10 enabled PFSWO1_1 to preferentially bind complex substrates, whereas the single-domain PFLoos_1 targeted simpler substrates. Notably, ELP pretreatment of corn stover significantly improved fermentation quality(pH and lactic acid) and nutritional value(neutral detergent fiber, acid detergent fiber, and water-soluble carbohydrates).Conclusions These findings indicate that ELPs are abundant in the rumen and play a synergistic role in lignocellulosic biomass conversion.展开更多
Background:The bacterial biofilm poses a significant challenge to traditional antibiotic therapy.There is a great need to develop novel antibiofilm agents combined with biofilm disrupting and bacteria-killing without ...Background:The bacterial biofilm poses a significant challenge to traditional antibiotic therapy.There is a great need to develop novel antibiofilm agents combined with biofilm disrupting and bacteria-killing without the dependence of antibiotic.Methods:Herein,we prepared ultrasound/magnetic field-responsive ferroferric oxide nanoparticles(Fe_(3)O_(4))/glucose oxidase microbubbles(FGMB)to form a cascade catalytic system for effective removing methicillin-resistant Staphylococcus aureus biofilms.FGMB were prepared through interfacial self-assembly of Fe_(3)O_(4) nanoparticles(NPs)and glucose oxidase(GOx)at the gas-liquid interface stabilized by surfactants.Under ultrasound/magnetic field stimulation,FGMB disrupted biofilm architecture through microbubble collapse-induced microjets and magnetically driven displacement.Simultaneously,ultrasound-triggered rupture of FGMB released GOx and Fe_(3)O_(4) NPs.Glucose can be oxidized by GOx to generate gluconic acid and hydrogen peroxide which was subsequently catalyzed into hydroxyl radicals by Fe_(3)O_(4) NPs,enabling chemical eradication of biofilm-embedded bacteria.Results:Optical microscopy images demonstrated that FGMB have spherical structure with average size of approximately 17μm.FGMB showed a 65.4%decrease in methicillin-resistant Staphylococcus aureus biofilm biomass and 1.1 log bacterial inactivation efficiency(91.2%),suggesting effective biofilm elimination.In vitro experimental results also indicate that FGMB have good biocompatibility.Conclusion:This antibiofilm strategy integrated dual modes of physical biofilm disruption with chemical bacteria-killing shows great potential as a versatile,non-resistant strategy for bacterial biofilm elimination.展开更多
Post-translational modification of spastin enables precise spatiotemporal control of its microtubule severing activity.However,the detailed mechanism by which spastin turnover is regulated in the context of neurite ou...Post-translational modification of spastin enables precise spatiotemporal control of its microtubule severing activity.However,the detailed mechanism by which spastin turnover is regulated in the context of neurite outgrowth remains unknown.Here,we found that spastin interacted with ubiquitin and was significantly degraded by K48-mediated poly-ubiquitination.Cullin3 facilitated spastin degradation and ubiquitination.RING-box protein 1,but not RING-box protein 2,acted synergistically with Cullin3 protein to regulate spastin degradation.Overexpression of Culin3 or BRX1 markedly suppressed spastin expression,and inhibited spastin-mediated microtubule severing and promotion of neurite outgrowth.Moreover,USP14 interacted directly with spastin to mediate its deubiquitination.USP14 overexpression significantly increased spastin expression and suppressed its ubiquitination and degradation.Although co-expression of spastin and USP14 did not enhance microtubule severing,it did increase neurite length in hippocampal neurons.Taken together,these findings elucidate the intricate regulatory mechanisms of spastin turnover,highlighting the roles of the Cullin-3–Ring E3 ubiquitin ligase complex and USP14 in orchestrating its ubiquitination and degradation.The dynamic interplay between these factors governs spastin stability and function,ultimately influencing microtubule dynamics and neuronal morphology.These insights shed light on potential therapeutic targets for neurodegenerative disorders associated with spastin defects.展开更多
基金supported by the National Natural Science Foundation of China(30870419,40971151)Strategic Priority Research Program Climate Change:Carbon Budget and Related Issues of the Chinese Academy of Sciences(XDA05050204)
文摘We used a litterbag method to investigate litter decomposition and related soil degradative enzyme activities across four seasons in a broad-leaved forest and a coniferous forest on Zijin Mountain in sub-tropical China. Across four seasons, we quantified litter mass losses, soil pH values, and related soil degradative enzyme activities. Litter decomposition rates differed significantly by season. Litter decomposi- tion rates of broadleaf forest leaves were higher than for coniferous for- ests needles across four seasons, and maximal differences in litter de- composition rates between the two litter types were found in spring.
基金This work was supported by the Shanghai Municipal Science and Technology Commission(No.16391902100)the Shanghai Construction Group(No.19JCSF-12)the Ministry of Agriculture,P.R.China and Shanghai Engineering Research Center of Plant Germplasm Resources(No.17DZ2252700).
文摘Rhizospheres can promote self-transmissible plasmid transfer,however,the corresponding mechanism has not received much attention.Plant-microbe remediation is an effective way to promote pollutant biodegradation;however,some pollutants,such as naphthalene,are harmful to plants and result in inefficient plant-microbe remediation.In this study,trans-fer of a TOL-like plasmid,a self-transmissible plasmid loaded with genetic determinants for pollutant degradation,among different bacteria was examined in bulk and rhizosphere soils as well as addition of maize root exudate and its artificial root exudate(ARE).The results showed that the numbers of transconjugants and recipients as well as bacterial metabolic activities,such as xylE mRNA expression levels and catechol 2,3-dioxygenase(C23O)activ-ities of bacteria,remained high in rhizosphere soils,when compared with bulk soils.The number of transconjugants and bacterial metabolic activities increased with the increasing exudate and ARE concentrations,whereas the populations of donor and recipient bacteria were substantially unaltered at all concentrations.All the experiments consistently showed that a certain number of bacteria is required for self-transmissible plasmid transfer,and that the increased plasmid transfer might predominantly be owing to bacterial metabolic activ-ity stimulated by root exudates and ARE.Furthermore,ARE addition increased naphthalene degradation by transconjugants in both culture medium and soil.Thus,the combined action of a wide variety of components in ARE might contribute to the increased plasmid transfer and naphthalene degradation.These findings suggest that ARE could be an effectively al-ternative for plant-microbe remediation of pollutants in environments where plants cannot survive.
文摘Fungi are the key agents in litter decomposition in forest ecosystems. However, the specific roles of the interactions between different fungal species during litter decomposition process are unclear. To evaluate the interactions, two fungi strains with significantly different morphs were isolated from the soils of Quercus acutissima forest and Pinus massoniana forest, and inoculated in the litter powder of Quercus acutissima leaves and Pinus massoniana needles with grown separately and in coexistence equally through a microcosm experiment. The enzyme activities were determined as a proxy for microbial activities. The results showed that the degradative enzymes involved in litter decomposition showed varying dynamics pattern during the incubation period. The interactions between the two fungi strains are synergism, and benefit to each other according to enzyme activities, suggesting that a fungi strain growth was accelerated by the presence of other fungi strain during litter decomposition process. However, the interactions of the two fungi strains were bilateral antagonism inoculated in the litter powder of Quercus acutissima leaves according to cellobiohydrolase activities. The synergism, despite bilateral antagonism in an exceptional case, may be an important factor controlling the fungal colonization and growth on litter substrate. The results implied that more fungal species may accelerate litter decomposition rates due to their mutual cooperation.
基金Funded partly by the National Natural Science Foundation of China(Nos.51172063,51202056,51372068)Hebei Natural Science Funds for Distinguished Young Scholar(No.B2014209304)+1 种基金Hebei Natural Science Funds for the Joint Research of Iron and Steel(No.B2014209314)Hebei Provincial Foundation for Returned Scholars
文摘We put forward a new approach for the synthesis of Ag@AgCl plasmonic photocatalyst via a hydrothermal-deposition-photoreduction method. The cetylmethylammonium chloride （CTAC） was used alone as both a source of reactants and surfactant. The structure of the prepared photocatalyst was determined by XRD, SEM, EDX and UV-Vis spectroscoscopy. The photocatalytic properties were investigated by degradation of an organic pollutant, Rhodamine B, under visible light irradiation. The results reveal that the experimental conditions have a great effect on the morphology of Ag@AgCl crystals. Ag@AgC1 crystal is cubic and the Ag@AgCl sample which is photoreduced for 40 min exhibits the highest photoactivity, and 80.6 % RhB is degraded after irradiation for 2 hours using this catalyst. The high photocatalytic activity observed is attributed to the surface plasmon resonance effect ofAg nanoparticles.
文摘Steviaside containing plant extracts have been used for degradation of persistent chloroorganic pesticides. Reactions between DDT and Steviaside or sum of extractive substances isolated from ground up part of plant Stevia were studied to give of less toxic DDE. Herein researches on studying interaction sum of polysaccharides of Stevia with DDT in various ratios resulted also. The GC-MS and GLC methods were used for analyzing degradation degree of pesticides and to determine obtained compounds. Treat HCCH by water extract of Stevia basically formed tetrachlorocyclo-hexadiene (HCH) with 86.9% yield and in particularly formed of tri-, tetrachlorobenzenes. The HCH formed in 79.7% on treat pesticide by 80% Steviaside. Degradation of HCCH and DDT by water extract of Stevia in a presence of Ana-basine in a ratio of 2:1:1 occur to degrade of HCCH up to 70-80%, and DDT on 25% - 30%.
基金This work was supported by the National High Technology Research and Development Program of China(863 Program)(Grant Nos.2002AA601170 and 2002A A601150).
文摘The genetic information encoding metabolic pathways for xenobiotic compounds in bacteria often resides on catabolic plasmids.The aim of the present work was to know the location of the genes for degrading 1,2,4-trichlorobenzen.In this paper a 1,2,4-trichlorobenzene-degrading strain THSL-1 was isolated from the soil of Tianjin Chemical Plant using 1,2,4-trichlorobenzene as the sole carbon source.The strain was identified as Pseudomonas stutzeri through morphologic survey and 16S rDNA sequence determination.A plasmid was discovered from strain THSL-1 by using the alkali lysis method.When the plasmid was transformed into E.coli.JM109 by the CaCl2 method,the transformant could grow using 1,2,4-trichlorobenzene as the sole carbon source and had the degradation function of 1,2,4-trichlorobenzene.Therefore,it could be deemed that the plasmid carried the degradative genes of 1,2,4-trichlorobenzene.The average size of the plasmid was finally determined to be 40.2 Kb using selectively three kinds of restricted inscribed enzymes(HindIII,BamHI,and XholI)for single cutting and double cutting the plasmid pTHSL-1,respectively.
基金the National Natural Science Foundation of China(21776109)the Foundation of State Key Laboratory of Coal Combustion(FSKLCCB1805).
文摘A degradative solvent extraction(DSE)method was proposed to upgrade low-rank coals(LRC)for their cascaded utilizations in a highly-dispersed medium.The derived products exhibited well improved properties in comparison to the raw LRCs.Previously,the LRCs were pre-dried to eliminate the potential impact of the varied water content of raw LRCs,but in light of the abundant water in fresh coals,the hydrolyzing effect of water on coals under heating,and the energy cost to pre-dry the LRCs,it is consequently essential to clarify the effect of water so as to verify the necessity of pre-drying process.In this study,the roles of inherent water and extra-added water were respectively investigated,using dried,raw and wet coals from two typical LRCs.The results show that increasing the moisture content of raw LRCs contributed to the extraction ability of DSE method without noticeably changing the elemental composition,chemical structure and thermal decomposition behavior of extractable products,thus pre-drying of LRCs before DSE treatment was proven unnecessary.Additionally,the roles of the inherent water were concluded as:1)leading to the formation of stable covalent bond during drying process;and 2)acting as H donor to promote extraction ability,while the added water can only function as H donor.Since excessive water will increase the pressure during DSE treatment and lead to the waste water treatment,the LRCs with a water content between 10%and 30%were consequently recommended for the practical application of DSE treatment.
文摘The escalating pace of industrialization has significantly intensified water pollution challenges,for instance,the persistent organic pollutants like methyl orange(MO).Conventional remediation techniques,such as adsorption and biological degradation,are often hampered by low efficiency and the risk of secondary pollution.Photocatalysis emerges as a promising sustainable alternative;however,the benchmark material titanium dioxide(TiO_(2))suffers from its intrinsic limitations,notably its wide bandgap energy(≥3.4 eV)restricting its activity to the region of the ultraviolet light and its rapid recombination of photogenerated charge carriers.To overcome these constraints,this research focused on synthesizing novel TiO_(2)/Sn_(3)O_(4) heterojunction composite photocatalysts via a solvothermal approach.Comprehensive characterization techniques confirmed the successful formation of the composite,which revealed that ultrathin Sn3O4 nanosheets uniformly coated TiO_(2) nanospheres.This unique architecture effectively reduced the overall crystallinity and introduced the beneficial oxygen vacancies.Under visible-light irradiation(λ≥420 nm),the optimized TiO_(2)/Sn3O4 composite exhibited the exceptional photocatalytic performance,which achieved 96%degradation of MO within just 60 minutes.The calculated apparent kinetic rate constant(0.103 min^(-1))was remarkably(5.15 times)higher than that of pristine TiO_(2).ESR experiments identified that hydroxyl radicals(·OH)was the predominant active species driving the degradation.Furthermore,cyclic degradation tests demonstrated its excellent material stability,with the composite retaining 85%of its initial efficiency after four consecutive reuse cycles.This work underscored the synergistic effects within the TiO_(2)/Sn_(3)O_(4) heterojunction,which significantly enhanced the visible-light absorption,charge separation,and photocatalytic activity,which provided the valuable insights for designing efficient,stable catalysts for the advanced environmental remediation applications.
基金CHN analysis(LECO,CHN628)for measuring mass fractions of Soluble and Residue was supported by Yukio Enda,Junko Kutsuna in Akita Industrial Technology Center.Appendix A.Supplementary data。
文摘A degradative solvent extraction method for upgrading low-rank coal was performed at 200-350◦C for 90 min to obtain a substance dissolved in the solvent at room temperature(Soluble).Because the resulting mixture exhibited a high carbon content without ash,it could be readily used as a fuel.Furthermore,deep eutectic solvents(DESs)have attracted attention for improving the Soluble yield and decreasing the oxygen content in Soluble.DES is known to cleave oxygen-containing functional groups in biomass and is considered effective for deoxidizing low-rank coal.Herein,DES was prepared by mixing choline chloride,FeCl3⋅6H2O,and Adaro subbituminous coal(AD)and then added to 1-methylnaphthalene(1-MN)in a non-polar solvent,followed by degradative solvent extraction in the range of 200-350◦C.The effects of reaction temperature and added DES amount on the product yield and the composition were evaluated.As the reaction temperature and amount of DES added increased,the Soluble yield and carbon content increased.It was also found that the thermal decomposition temperature and oxygen content decreased with the increasing DES amounts.This decrease indicates that DES promotes the deoxygenation and decomposition of AD and increases the soluble yield of the fuel source.
基金supported by the Bingtuan Industrial Technology Research Institute,Bingtuan New materials Research Institute innovation platform project,Research initiation project of Shihezi University(No.RCZK202330)the Science and Technology Program-Regional Innovation Guidance Program(No.2023ZD080)Tianchi Talent Project(No.CZ002735).
文摘The microbial degradation of aromatic organic pollutants is incomplete due to their metabolic characteristics,which can easily produce certain highly toxic intermediates.Therefore,this article designs a dual template molec-ularly imprinted sensor(DTMIP/Fe-Mn@C)for iron manganese metal nanomaterials,prepared Fe-Mn@C com-posite materials by a one pot method were coated on the surface of glassy carbon electrodes and covered with molecularly imprinted membranes through electropolymerization and elution methods,achieving real-time de-tection of specific intermediate products 2-methylbutyric acid(2-MBA)and 3-methylbutyric acid(3-MBA)de-graded by azo dyes.In order to determine the detection sensitivity and intensity range of the sensor,optimization experiments were conducted on various parameters that affect the detection performance,such as the type of func-tional monomer and its composition ratio with the template molecule,detection time window,environmental pH value,etc.Finally,o-Phenylenediamine was determined as the functional monomer,with a molar ratio of 1:1:6 to the template molecules 2-MBA and 3-MBA.Electrochemical testing was conducted in a neutral environment with an incubation time of 5 min and pH=7.The results indicate that the sensor has a relatively wide detection range,high sensitivity,obvious recognition features,and excellent stability for 2-MBA and 3-MBA.This new dual template molecularly imprinted sensor can quickly and accurately determine the safety of highly toxic interme-diates in the degradation process of aromatic organic pollutants,providing a theoretical basis and application potential for trace detection and real-time monitoring.
基金supported by the Youth Talent Project of China Nuclear Power Engineering Co.,Ltd.(KY24045).
文摘While nuclear energy represents a low-carbon and high-efficiency energy source that plays a vital role in the global energy mix,the limitations of spent fuel reprocessing technology pose a major challenge to its sustainable development.The PUREX(plutonium uranium redox extraction)process is currently the dominant nuclear fuel reprocessing technology in the world.However,the key extractant in this process is tributyl phosphate(TBP),which degrades under intense radiation,high temperatures,and strong acidity.This leads to the production of dibutyl phosphate,monobutyl phosphate,and other degradation byproducts,which may reduce the extraction efficiency and trigger third-phase formation and equipment corrosion.This paper systematically reviews the degradation mechanisms of TBP and its diluents,the analytical technique suitable for characterizing degradation products,and the impact of degradation products on the post-treatment process.Additionally,optimization strategies employed for suppressing third-phase formation are discussed.This study offers a theoretical foundation and technical insights in optimizing the PUREX process and ensuring the safe operation of the post-treatment process.
基金financially supported by the National Key Research and Development Program of China(2022YFF1102500)the Key Research and Development Projects in Hubei Province,China(2021BCA113).
文摘Zearalenone(ZEN),a mycotoxin present in cereals,poses significant health risks to animals and humans due to its estrogenic effects.Numerous studies on the enzymatic detoxification of ZEN have predominantly focused on reducing the parent toxin to assess the enzyme’s efficacy,yet there is limited research on the identification and toxicity evaluation of the enzymatic degradation products.This study investigated the enzymatic degradation mechanisms of ZEN using commercial peroxidase(POD)and laccase(LC),with a focus on identifying degradation products and assessing their hepatotoxicity effects.Molecular docking and dynamics simulations elucidated the binding mechanisms between these enzymes and ZEN,revealing strong interactions that facilitate efficient detoxification.Subsequent analysis employing ultra-high performance liquid chromatography-high resolution mass spectrometry(UHPLC-HRMS)successfully identified crucial degradation products.Hepatic toxicity of the enzymatic degradation products was comprehensively assessed in HepaRG liver cells through systematic measurements of cell viability,oxidative stress,apoptosis,mitochondrial membrane potential,and molecular metabolic profiles.Our findings demonstrate that both POD and LC exhibit significant efficacy in mitigating hepatocyte toxicity induced by ZEN,thereby highlighting their potential utility in enhancing food safety.This research provides essential data for safety evaluation regarding enzymatic detoxification of ZEN while offering theoretical and technical resources for risk assessment related to mycotoxin enzymatic detoxification.
基金financially supported by the National Natural Science Foundation of China (No.52100076)the Fundamental Research Funds for the Central Universities (No.2023MS064)。
文摘The escalating global issues of water scarcity and pollution emphasize the critical need for the rapid development of efficient and eco-friendly water treatment technologies.Photoelectrocatalytic technology has emerged as a promising solution for effectively degrading refractory organic pollutants in water under light conditions.This review delves into the advancements made in the field,focusing on strategies to enhance the generation of active species by modulating the micro-interface of the photoanode.Strategies,such as morphological control,element doping,introduction of surface oxygen vacancies,and construction of heterostructures,significantly improve the separation efficiency of photogenerated charges and the generation of active species,thereby boosting the efficiency of photoelectrocatalytic performance.Furthermore,the review explores the potential applications of photoelectrocatalytic technology in organic pollutant degradation in solutions.It also outlines the current challenges and future development directions.Despite its remarkable laboratory success,practical implementation of photoelectrocatalytic technology encounters obstacles related to stability,cost-effectiveness,and operational efficiency.Future investigations need to focus on optimizing the performance of photoelectrocatalytic materials and exploring strategies for upscaling their application in real water treatment scenarios.
基金supported by the Agriculture Research System of China of MOF and MARA[grant number CARS-14-1-29]“Double First-Class”Project for Undergraduate-Cultivating Quality Enhancement Key Programme in Food Science and Engineering at Henan University of Technology[grant number HN-HautFood IAEM-025].
文摘Roasting constitutes a critical stage in sesame oil production,where the thermal degradation of pectic polysaccharide initiates fundamental chemical transformations including caramelization,Maillard processes,lipid oxidation and Strecker degradation.This study systematically examines the structural,chemical and oil antioxidant capacity of sesame hull-derived pectic polysaccharides(URA and URB)under 160–220℃,and their impacts on sesame oil oxidative stability.The results demonstrate temperature-dependent molecular restructuring of URA and URB with molecular weights increasing proportionally and reduced total yields by 42.73%until 220℃.Furfural and organic acids were identified as primary pyrolysis products,accompanied by volatile aromatic compounds including furans,benzenes,and phenols.Sesame oil with the mixture of URA and URB(HSO-URA/B)exhibited optimal thermal antioxidant performance,demonstrating improved sesame oil oxidative stability as evidenced by peroxide value(0.07–0.81 g/100 g)and oxidative stability index(22.6 h).This work provides a scientific foundation for optimizing sesame oil quality while transforming hull byproducts into valueadded food ingredients.
基金Project supported by the National Natural Science Foundation of China(Nos.12172149,12172151,and 12202378)the MOE Key Laboratory of Fututer Intelligent Manufacturing Technologies for High-End Equipment of China(No.FIMFYUST-2025B07)+1 种基金the Guangzhou Municipal Bureau of Science and Technology of China(No.SL2023A04J01461)the Ministry of Science and Technology of China(No.G20221990122)。
文摘This study focuses on a new and high-efficiency approach in a unified sense of accurately simulating strength-degrading effects for geomaterials,including non-symmetric hardening-to-softening effects in tension and compression as well as non-symmetric tensile and compressive stiffness-degrading effects during unloading.It is intended to bypass both modeling and numerical complexities involved in existing approaches.To this goal,new elastoplastic equations are established with new numerical techniques.With a decoupling technique of treating tension-compression asymmetry,the foregoing complex effects are automatically incorporated as inherent response features of the new elastoplastic equations,thus bypassing usual modeling complexities.A new numerical technique of renormalizing piecewise spline functions is introduced to resolve the central yet tough issue of obtaining accurate and unified expressions for the tensile and compressive strength functions,thus bypassing usual numerical complexities and uncertainties in treating numerous unknown parameters and multiple ad hoc criteria.As such,the new approach is not only of wide applicability for various geomaterials but also of high computational efficiency with no more than three adjustable parameters.Toward validating the efficacy of the new approach,numerical examples for granite,salt rock,and sandstone-concrete combined body as well as plain concrete,high-performance concrete,and ultrahigh-performance concrete are presented by comparing model predictions with multiple data sets for strength-degrading effects in tension and compression.
基金supported by the National Key Research and Development Program of China(2025YFE0103800,2023YFE0102600,2024YFE0214200).
文摘Livestock farming is a critical pillar of Tajikistan’s national economy and livelihood security.However,significant economic challenges in the country have led to the degradation of grassland ecosystems.This degradation has not only reduced the productivity of grassland ecosystems but also severely impacted their ecological functions.A particularly concerning consequence is the threat to biodiversity,as the survival and persistence of endemic,rare,and endangered plant species are at serious risk,thereby diminishing the value of species’genetic resources.Based on the data from multiple sources such as literature reviews,field observations,and national statistics,this study employed a systematic literature review and meta-analysis to investigate the current status,causes of degradation,and restoration measures for grassland ecosystems in Tajikistan.The results revealed that Tajikistan’s grassland ecosystems support exceptionally high plant species diversity,comprising over 4500 vascular plant species,including nearly 1500 endemic and sub-endemic taxa that constitute a unique genetic reservoir.These ecosystems are experiencing severe degradation,characterized by significantly reduced vegetation cover and declining species richness.Palatable forage species are increasingly being displaced by unpalatable,thorny,and poisonous species.The primary drivers of degradation include excessive grazing pressure,which disrupts plant reproductive cycles and regeneration capacity,habitat fragmentation due to urbanization and infrastructure development,and uncontrolled exploitation of medicinal and edible plants.Climate change,particularly rising temperatures and altered precipitation patterns,further exacerbates these anthropogenic pressures.Ecological restoration experiments suggested that both ecosystem productivity and plant species diversity are significantly enhanced by systematic reseeding trials using altitude-adapted native species.These findings underscore the necessity of establishing scientifically grounded approaches for ecological restoration.
基金funded by the National Natural Science Foundation of China(grant nos.32372905)。
文摘Background Sustainable livestock production is essential for food security and environmental management. Lignocellulosic biomass can be used in animal feed, thereby reducing feed production costs and enhancing sustainability. Expansin-like proteins(ELPs) play essential roles in plant cell wall degradation, yet their functions remain largely underexplored in rumen microbes. The purpose of this study was to investigate the effects of rumen microbial ELPs on lignocellulose degradation.Results This study systematically identified 396 ELPs within the rumen microbiota, uncovering remarkable diversity, particularly among anaerobic fungi. Three representative ELPs from Pecoramyces ruminantium F1(PFLoos_1, PFSWO1_1, PFSWO2_1) were selected for biochemical characterization. While PFSWO2_1 could not be expressed, PFLoos_1 and PFSWO1_1 exhibited significant synergy with cellulases. The CBM10-containing PFSWO1_1 demonstrated superior thermal stability(up to 65 ℃) and substrate affinity, increasing rice straw hydrolysis efficiency by 21.6%(reducing sugar yield) compared to cellulase alone. Structural analyses revealed that CBM10 enabled PFSWO1_1 to preferentially bind complex substrates, whereas the single-domain PFLoos_1 targeted simpler substrates. Notably, ELP pretreatment of corn stover significantly improved fermentation quality(pH and lactic acid) and nutritional value(neutral detergent fiber, acid detergent fiber, and water-soluble carbohydrates).Conclusions These findings indicate that ELPs are abundant in the rumen and play a synergistic role in lignocellulosic biomass conversion.
基金supported by the National Natural Science Foundation of China(22375101)the Natural Science of Colleges and Universities in Jiangsu Province(24KJB430027).
文摘Background:The bacterial biofilm poses a significant challenge to traditional antibiotic therapy.There is a great need to develop novel antibiofilm agents combined with biofilm disrupting and bacteria-killing without the dependence of antibiotic.Methods:Herein,we prepared ultrasound/magnetic field-responsive ferroferric oxide nanoparticles(Fe_(3)O_(4))/glucose oxidase microbubbles(FGMB)to form a cascade catalytic system for effective removing methicillin-resistant Staphylococcus aureus biofilms.FGMB were prepared through interfacial self-assembly of Fe_(3)O_(4) nanoparticles(NPs)and glucose oxidase(GOx)at the gas-liquid interface stabilized by surfactants.Under ultrasound/magnetic field stimulation,FGMB disrupted biofilm architecture through microbubble collapse-induced microjets and magnetically driven displacement.Simultaneously,ultrasound-triggered rupture of FGMB released GOx and Fe_(3)O_(4) NPs.Glucose can be oxidized by GOx to generate gluconic acid and hydrogen peroxide which was subsequently catalyzed into hydroxyl radicals by Fe_(3)O_(4) NPs,enabling chemical eradication of biofilm-embedded bacteria.Results:Optical microscopy images demonstrated that FGMB have spherical structure with average size of approximately 17μm.FGMB showed a 65.4%decrease in methicillin-resistant Staphylococcus aureus biofilm biomass and 1.1 log bacterial inactivation efficiency(91.2%),suggesting effective biofilm elimination.In vitro experimental results also indicate that FGMB have good biocompatibility.Conclusion:This antibiofilm strategy integrated dual modes of physical biofilm disruption with chemical bacteria-killing shows great potential as a versatile,non-resistant strategy for bacterial biofilm elimination.
基金supported by the National Natural Science Foundation of China,No.32071033(to MT)Basic and Applied Basic Research Foundation of Guangdong Province,Nos.2023A1515010140(to MT),2022A1515140169(to MT),2022A1515111096(to ZC)+3 种基金Science and Technology Project of Guangzhou,Nos.202201010015(to YL),2023A03J0790(to TJ)Basic and Applied Basic Research Foundation of Guangzhou,No.2023A04J1285(to ZC)Medical Research Foundation of Guangdong Province,No.A2023147(to ZC)Health Science and Technology Project of Guangzhou,No.20221A011039(to TJ)。
文摘Post-translational modification of spastin enables precise spatiotemporal control of its microtubule severing activity.However,the detailed mechanism by which spastin turnover is regulated in the context of neurite outgrowth remains unknown.Here,we found that spastin interacted with ubiquitin and was significantly degraded by K48-mediated poly-ubiquitination.Cullin3 facilitated spastin degradation and ubiquitination.RING-box protein 1,but not RING-box protein 2,acted synergistically with Cullin3 protein to regulate spastin degradation.Overexpression of Culin3 or BRX1 markedly suppressed spastin expression,and inhibited spastin-mediated microtubule severing and promotion of neurite outgrowth.Moreover,USP14 interacted directly with spastin to mediate its deubiquitination.USP14 overexpression significantly increased spastin expression and suppressed its ubiquitination and degradation.Although co-expression of spastin and USP14 did not enhance microtubule severing,it did increase neurite length in hippocampal neurons.Taken together,these findings elucidate the intricate regulatory mechanisms of spastin turnover,highlighting the roles of the Cullin-3–Ring E3 ubiquitin ligase complex and USP14 in orchestrating its ubiquitination and degradation.The dynamic interplay between these factors governs spastin stability and function,ultimately influencing microtubule dynamics and neuronal morphology.These insights shed light on potential therapeutic targets for neurodegenerative disorders associated with spastin defects.
