This study establishes and validates a method for the precise quantification of aquatic microbial loads using microbial diversity absolute quantitative sequencing.By adding synthetic spike-in DNA to water samples from...This study establishes and validates a method for the precise quantification of aquatic microbial loads using microbial diversity absolute quantitative sequencing.By adding synthetic spike-in DNA to water samples from the Dahei River prior to DNA extraction and 16S rRNA gene sequencing,it generates standard curves to convert sequencing data into absolute microbial copy numbers.The method,which is proved highly accurate(R^(2)>0.99),reveals a clear contrast between the river sites:the upstream community has not only a significantly higher total microbial load but also a completely different makeup of species compared to the downstream site.This approach effectively overcomes the limitations of relative abundance analysis,providing a powerful tool for environmental monitoring,and proposes key steps for future standardization to ensure data comparability and integration.展开更多
Background The enteric methane inhibitor 3-nitrooxypropanol(3-NOP)inhibits the key enzyme in ruminal methanogenesis,but whether short-term(ST)and long-term(LT)dietary supplementation has similar effects on rumen micro...Background The enteric methane inhibitor 3-nitrooxypropanol(3-NOP)inhibits the key enzyme in ruminal methanogenesis,but whether short-term(ST)and long-term(LT)dietary supplementation has similar effects on rumen microbiota in beef cattle and how microbes change after 3-NOP withdrawal have not been studied.This study investigated changes in rumen bacteria,archaea,and protozoa after ST and LT dietary supplementation and removal of 3-NOP using metataxonomic analysis.Results A total of 143 rumen samples were collected from two beef cattle studies with 3-NOP supplementation.The ST study(95 samples)used eight ruminally cannulated beef cattle in a 4×4 Latin square design with four 28-d of 3-NOP treatments[mg/kg of dry matter(DM)]:control:0,low:53,med:161,and high:345.The LT study(48 samples)was a completely randomized design with two 3-NOP treatments[control:0,and high:280 mg/kg of DM)fed for 112-d followed by a 16-d withdrawal(without 3-NOP).Bacterial and archaeal communities were significantly affected by 3-NOP supplementation but limited effects on protozoal communities were observed.Under ST supplementation,the relative abundances of Prevotella,Methanobrevibacter(Mbb.)ruminantium,Methanosphaera sp.ISO3-F5,and Entodinium were increased(Q<0.05),whereas those of Mbb.gottschalkii and Epidinium were decreased(Q<0.05)with 3-NOP supplementation.In LT study,relative abundances of Mbb.ruminantium,and Methanosphaera sp.Group5 were increased(Q<0.05),while those of Saccharofermentans and Mbb.gottschalkii were decreased(Q<0.05)with 3-NOP supplementation.Comparison between 3-NOP supplementation and the withdrawal revealed increased relative abundances of Clostridia UCG-014 and Oscillospiraceae NK4A214 group and decreased those of Eubacterium nodatum group and Methanosphaera sp.Group5(P<0.05)after 3-NOP withdrawal.Further comparison of rumen microbiota between control and 3-NOP withdrawal showed significantly higher(P=0.029)relative abundances of Eggerthellaceae DNF00809,p-1088-a5 gut group,and Family XII UCG-001 in control group while no significant differences were detected for archaea and protozoa.Microbial network analysis revealed that microbial interactions differed by both 3-NOP dose and durations.Conclusions Both ST and LT supplementation affected overall rumen microbial profile,with individual microbial groups responded to 3-NOP supplementation differently.After 3-NOP withdrawal,not all microbes showed recovery,indicating that the 3-NOP driven shifts were only partially reversible.These findings provide an understanding of the effects of 3-NOP on rumen microbial communities and their adaptability to methane mitigation strategies.展开更多
Objective Evidence suggests that depleted gut microbialα-diversity is associated with hypertension;however,whether metabolic markers affect this relationship remains unknown.We aimed to determine the potential metabo...Objective Evidence suggests that depleted gut microbialα-diversity is associated with hypertension;however,whether metabolic markers affect this relationship remains unknown.We aimed to determine the potential metabolites mediating the associations ofα-diversity with blood pressure(BP)and BP variability(BPV).Methods Metagenomics and plasma targeted metabolomics were conducted on 523 Chinese participants from the MetaSalt study.The 24-hour,daytime,and nighttime BP and BPV were calculated based on ambulatory BP measurements.Linear mixed models were used to characterize the relationships betweenα-diversity(Shannon and Chao1 index)and BP indices.Mediation analyses were performed to assess the contribution of metabolites to the observed associations.The influence of key metabolites on hypertension was further evaluated in a prospective cohort of 2,169 participants.Results Gut microbial richness(Chao1)was negatively associated with 24-hour systolic BP,daytime systolic BP,daytime diastolic BP,24-hour systolic BPV,and nighttime systolic BPV(P<0.05).Moreover,26 metabolites were strongly associated with richness(Bonferroni P<0.05).Among them,four key metabolites(imidazole propionate,2-hydroxy-3-methylbutyric acid,homovanillic acid,and hydrocinnamic acid)mediated the associations between richness and BP indices(proportions of mediating effects:14.1%–67.4%).These key metabolites were also associated with hypertension in the prospective cohort.For example,each 1-standard deviation unit increase in hydrocinnamic acid significantly reduced the risk of prevalent(OR[95%CI]=0.90[0.82,0.99];P=0.03)and incident hypertension(HR[95%CI]=0.83[0.71,0.96];P=0.01).Conclusion Our results suggest that gut microbial richness correlates with lower BP and BPV,and that certain metabolites mediate these associations.These findings provide novel insights into the pathogenesis and prevention of hypertension.展开更多
Elevation patterns and assembly processes of soil microbial community structures are essential for understanding biogeo-chemical processes in mountain systems.Differences in soil properties caused by elevation gradien...Elevation patterns and assembly processes of soil microbial community structures are essential for understanding biogeo-chemical processes in mountain systems.Differences in soil properties caused by elevation gradients can regulate the spatial distribu-tion and network complexity of the community structure.To explore the variations in soil microbial community structures and their as-sembly mechanisms across different elevations of the Changbai Mountains,as well as their responses to environmental factors,we col-lected microbial samples along an elevational gradient(seven elevations containing four vegetation zones)on the western slope of the Changbai Mountains using the method of metagenomic sequencing.The results showed a significant difference(P<0.05)for the Chao1 index across different elevations,but no significant difference was observed for the Shannon and Simpson indices.With increasing elev-ation,the number of nodes and links in the microbial network gradually decreased.Acidobacteria were highly connected to many nodes.The microbial communities indicated a significant distance-decay relationship(P<0.001)and were affected more by stochastic pro-cesses along the elevation gradient.The results of the Structural Equation Model(SEM)showed that elevation had direct significant ef-fect on carbon(C,P<0.01),nitrogen(N,P<0.01),and phosphorus(P,P<0.05)and weak negative effect on their ecological stoi-chiometry.Elevation was one of the major variables contributing to microbial network topology.The contribution of C and N to micro-bial network complexity was higher than that of P.Our study provides valuable insights into the responses of soil microbial communit-ies to elevation variations.展开更多
Microbial contamination and the resulting corrosion in aircraft fuel system pose a serious threat to flight safety.Revealing the corrosion behavior and mechanism of fuel-degrading microorganisms on tank materials is c...Microbial contamination and the resulting corrosion in aircraft fuel system pose a serious threat to flight safety.Revealing the corrosion behavior and mechanism of fuel-degrading microorganisms on tank materials is crucial for developing effective mitigation strategies.In this study,the corrosion mechanisms of two representative hydrocarbon-degrading bacteria,Alcanivorax dieselolei and Microbacterium oxydans,toward AA7075 aluminum alloy,were systematically investigated.A combination of biofilm characterization,electrochemical testing,and surface/corrosion product characterization was employed.Both strains markedly accelerated the corrosion of AA7075,as evidence by the progressive decrease in polarization resistance and the pronounced rightward shift of the potentiodynamic polarization curves.Moreover,the difference between the pitting potential(E_(pit))and the corrosion potential(E_(corr))(ΔE=E_(pit)‒E_(corr))decreased due to microbial activities,indicating a pronounced tendency toward accelerated pitting corrosion.Corrosion morphology analysis revealed that both microbes promoted localized pitting corrosion.Furthermore,analysis of aviation kerosene composition indicated that both bacteria accelerated the degradation of C8 and C9 alkanes.These findings highlight the multiple threats of microbial contamination,material degradation,and fuel quality deterioration in fuel systems and underscore the need for targeted protection strategies for marine aviation operations.展开更多
Background An imbalance in the rumen microbiota caused by high-concentrate diets(HCD)is a significant endogenous trigger of mastitis.However,the underlying mechanisms remain largely unknown.Microbial extracellular ves...Background An imbalance in the rumen microbiota caused by high-concentrate diets(HCD)is a significant endogenous trigger of mastitis.However,the underlying mechanisms remain largely unknown.Microbial extracellular vesicles(mEVs)are critical mediators of microbe-host communication.However,the role of mEVs in rumen microbiota-mediated mastitis has not yet been reported.In this study,we used an HCD-induced rumen microbiota dysbiosis model to investigate the role of mEVs-derived from rumen microbiota in the pathogenesis of mastitis.Results Our results indicate that HCD leads to mastitis and systemic inflammation.Meanwhile,HCD-fed goats exhibited substantial rumen microbiota dysbiosis and the disruption of the rumen barrier.Transplanting rumen microbiota from HCD goats into mice induced both mastitis and systemic inflammation in the recipients.Specifically,HCD increases the production of mEVs carrying microbial DNA,which can translocate across the compromised rumen barrier to the mammary gland,triggering a mammary inflammatory response via activation of the cGAS-STING-NF-κB/NLRP3 pathway.Furthermore,treating mice with mEVs isolated from the rumen fluid of HCD goats directly induced mastitis,whereas depletion of microbial DNA attenuated mEVs-induced mastitis.Conclusion Our findings suggest that HCD induces rumen microbiota dysbiosis and impairs rumen barrier function.This dysfunction leads to an increase in microbial DNA-containing mEVs,which subsequently leak into the mammary gland.Once there,these mEVs activate the cGAS-STING-NF-κB/NLRP3 signaling pathway,ultimately inducing mastitis.This study provides a new perspective on the“rumen microbiota-mammary gland axis”and enhances the understanding of the pathogenesis of mastitis.展开更多
In this work,ofloxacin(OFL),a kind of frequently detected antibiotic in groundwater,was selected to explore its impact(at ng/L-μg/L-level)on denitrification performance in an autotrophic denitrification system driven...In this work,ofloxacin(OFL),a kind of frequently detected antibiotic in groundwater,was selected to explore its impact(at ng/L-μg/L-level)on denitrification performance in an autotrophic denitrification system driven by pyrite/sulfur(FeS2/S0).Results showed that OFL restrained nitrate removal efficiency,and the inhibition degree was positively related to the concentration of OFL.After being exposed to increased OFL(200 ng/L-100μg/L)for 69 days,higher inhibition of electron transport activity(ETSA),enzyme activities of nitrate reductase(NAR),and nitrite reductase(NIR)were acquired.Meanwhile,the extracellular protein(PN)content of sludge samples was remarkably stimulated by OFL to resist the augmented toxicity.OFL contributed to increased microbial diversity and sulfur/sulfide oxidation functional genes in ng/L-level bioreactors,whereas led to a decline inμg/L level experiments.With OFL at concentrations of 200 ng/L and 100μg/L,the whole expression of 10 key denitrification functional genes was depressed,and the higher the OFL concentration,the lower the expression level.However,no significant proliferation of antibiotic resistance genes(ARGs)either in 200 ng/L-OFL or 100μg/L-OFL groups was observed.Two-factor correlation analysis results indicated that Thiobacillus,Anaerolineae,Anaerolineales,and Nitrospirae might be the main hosts of existing ARGs in this system.展开更多
Microplastics (MPs), fluoride (FR), and fungicide mancozeb (MZ) are common contaminants in soil. However, there is no information about the combined impacts of MPs, FR, and MZ on tomato plant growth features in the li...Microplastics (MPs), fluoride (FR), and fungicide mancozeb (MZ) are common contaminants in soil. However, there is no information about the combined impacts of MPs, FR, and MZ on tomato plant growth features in the literature. This study aimed to investigate the effects of combined application of MPs, FR, and MZ (both analytical grade and commercial) on the growth and development of tomato plants and metagenomics of rhizosphere soil. A pot experiment was set up in an artificial greenhouse with two sets of treatments. One set was the combined application of MPs, FR, and analytical grade MZ (B2) and a control without the application of MPs, FR, and MZ (W2), and the other set was the combined application of MPs, FR, and commercial MZ (B3) and a control without the application of MPs, FR, and MZ (W3). No detrimental effects of MPs, FR, and MZ were detected on the growth parameters of tomato plants, including the number of leaves and chlorophyll concentration. However, tomato roots showed knot and nodulation-type structures, and metabolomic profiling revealed that combined exposure to MPs, FR, and MZ profoundly reprogrammed the primary metabolism in tomato roots, with marked alterations in carbohydrate and amino acid pathways. Metagenome whole genome sequencing showed that the B2 and B3 treatments profoundly affected soil microbial community composition, diversity, gene abundances, and functional gene variations compared to W2 and W3. Proteobacteria became the dominating phylum in B2 and B3, causing a significant shift in the microbiome. Its abundance soared to 66.7% in B2 and 75.4% in B3, compared to only 35.9% in W2 and 28.9% in W3. On the other hand, Actinobacteria decreased significantly from 55.6% in W2 and 63.8% in W3 to 18.1% in B2 and 9.6% in B3. This study highlights the microbial shifts due to combined application of MPs, FR, and MZ, providing evidence for understanding their environmental risks.展开更多
Effective vegetation reconstruction plays a vital role in the restoration of desert ecosystems.However,in reconstruction of different vegetation types,the community characteristics,assembly processes,and functions of ...Effective vegetation reconstruction plays a vital role in the restoration of desert ecosystems.However,in reconstruction of different vegetation types,the community characteristics,assembly processes,and functions of different soil microbial taxa under environmental changes are still disputed,which limits the understanding of the sustainability of desert restoration.Hence,we investigated the soil microbial community characteristics and functional attributes of grassland desert(GD),desert steppe(DS),typical steppe(TS),and artificial forest(AF)in the Mu Us Desert,China.Our findings confirmed the geographical conservation of soil microbial composition but highlighted decreased microbial diversity in TS.Meanwhile,the abundance of rare taxa and microbial community stability in TS improved.Heterogeneous and homogeneous selection determined the assembly of rare and abundant bacterial taxa,respectively,with both being significantly influenced by soil moisture.In contrast,fungal communities displayed stochastic processes and exhibited sensitivity to soil nutrient conditions.Furthermore,our investigation revealed a noteworthy augmentation in bacterial metabolic functionality in TS,aligning with improved vegetation restoration and the assemblage of abundant bacterial taxa.However,within nutrient-limited soils(GD,DS,and AF),the assembly dynamics of rare fungal taxa assumed a prominent role in augmenting their metabolic capacity and adaptability to desert ecosystems.These results highlighted the variations in the assembly processes and metabolic functions of soil microorganisms during vegetation reestablishment and provided corresponding theoretical support for anthropogenic revegetation of desert ecosystems.展开更多
Soil nitrogen(N)cycling is one of the most critical biogeochemical cycles,and N cycling-related microorganisms are the primary driving force behind N cycling in natural environments.The large karst sinkholes in China,...Soil nitrogen(N)cycling is one of the most critical biogeochemical cycles,and N cycling-related microorganisms are the primary driving force behind N cycling in natural environments.The large karst sinkholes in China,known as Tiankengs,harbor abundant unique biological resources due to their particular environmental conditions.However,N cycling-related microorganisms in Tiankeng soils and their connection to ecosystem processes remain poorly studied.In this study,we investigated the distribution patterns and genomic diversity of N cycling-related microorganisms both inside and outside the Luohun cave Tiankeng in Guizhou,China,utilizing high-throughput sequencing and other techniques.The results indicated that the diversities and abundances of denitrifying bacteria,ammonia-oxidizing bacteria,and ammonia-oxidizing archaea communities inside the Tiankeng were higher than those outside the Tiankeng;however,the microbial network relationships were more fragile inside the Tiankeng.The most abundant species of denitrifying bacteria,ammonia-oxidizing bacteria,and ammonia-oxidizing archaea inside the Tiankeng were unclassified_p_Proteobacteria(47.8%),unclassified_k_norank(AOB,OTU121,37.3%),and unclassified_g_norank_f_norank_o_norank_c_environmental_samples(55.7%),respectively;outside the Tiankeng,they were unclassified_k_norank_d_bacteria(54.5%),unclassified_k_norank(AOB,OTU121,48.1%),and unclassified_k_norank(AOA,OTU70,49.6%),respectively.Additionally,the N content inside the Tiankeng was significantly lower(P<0.05)under the influence of these N cycling-related microorganisms,whereas the nutrient contents were higher than that outside the Tiankeng.To the best of our knowledge,this is the first report on the crucial microbial distribution patterns driving N cycling in karst Tiankengs and provides new insights into the structure and potential functions of N cycling-related microorganisms in the unique ecological environment of fragile Tiankeng ecosystems.展开更多
This study was conducted at the scientific center of Brazzaville. The objective was to assess the microbial characteristics and enzymes activities in the rhizosphere soil of Cajanus cajan and Milletia lauurentii. Thes...This study was conducted at the scientific center of Brazzaville. The objective was to assess the microbial characteristics and enzymes activities in the rhizosphere soil of Cajanus cajan and Milletia lauurentii. These plants have great importance in food and forestry. Microbial diversity management in the rhizosphere is the key for sustainable crop production or forest durability. DNA metagenomic sequencing was used to analyze the whole bacterial diversity, the microbial biomass was determinate by the fumigation-extraction method and the enzymes by the p-nitrophenol-β-D-glucoside for β-glucosidase, the p-nitrophenyl-N-acetyl-β-D-glucosaminide for β-Glucosaminidase. Dehydrogenase and acid phosphatase were quantified using 2,3,5-tryphenyl tetrazolium chloride and p-nitophenylphosphate respectively. The results show that, in Cajanus cajan culturable bacteria genera were mainly Acidobacterium, Skermanella, Rhodoplanes, Bacillus, Chloroflexus, Steroidobacter, Sphingomonas and Bradyrhizobium while in Milletia laurentii: Rhodoplanes, Bradyrhizobium, Bacillus, Sphingobacterium, Acidobacterium, Mesorhizobium, Nitrospira were the principal genera. In the two rhizosphere soils investigated, the uncultured bacteria exhibited relatively higher abundance, often for the same genera, than culturable bacteria. Metagenomic studies have revealed more bacterial diversity in each compared to when culturable bacteria were taken into account alone. The MBC and MBN were higher in the rhizosphere of Milletia than in rhizosphere of Cajanus. The same trend was observed with the enzyme activities. PCA of culturable and NMDS of unculturable soil bacteria genera shows that factors mainly involved in the carbon cycle such as MBC, members of the microbial community i.e. Acidobacterium, Skermanella, Chloroflexus, sand, C, β-glucosaminidase and dehydrogenase, were strongly correlated with Cajanus cajan. On the other hand, the MBN, Mesorhizobium, Bradyrhizobium, Burkholderia, Nitrospira, Nitratireductor, N, NH4, β-glucosidase and acid phosphatase involved in the N cycling, silt and clay were predominantly founded in the rhizosphere soil of Milletia laurentii. This study showed that metagenomic sequencing could improve the assessment of the microbial diversity structure of the rhizosphere.展开更多
Soil organic carbon(SOC)plays a crucial role in mangrove blue carbon formation,yet the differences in microbemediated underlying SOC sequestration between introduced and native mangroves remain unclear.Here,we compare...Soil organic carbon(SOC)plays a crucial role in mangrove blue carbon formation,yet the differences in microbemediated underlying SOC sequestration between introduced and native mangroves remain unclear.Here,we compared the SOC pool,including recalcitrant organic carbon(ROC)and labile carbon pools,as well as three residual carbon sources(amino sugars,lignin phenols,and lipids)in sediments between mangroves of introduced Sonneratia apetala and native Kandelia obovata,and further connected them with microbial life strategies and C metabolism capability.The results showed that SOC accumulation in S.apetala(SA)sediment was about 30%-50% of that in K.obovata(KO)sediment.ROC was the dominant form of SOC in long-term sequestration(76%-83%),while lignin phenols,amino sugars,and lipids were important sources of ROC.In S.apetala sediments,the ROC content was positively correlated with amino sugars,resulting from the more r-strategist microbes that can rapidly convert plant-derived carbon into microbial biomass,which is subsequently transformed into microbial necromass.In contrast,in K.obovata sediments,ROC content showed a stronger positive correlation with the concentrations of lignin phenols and lipids.More K-strategist fungi in the topsoil of K.obovata increased enzyme activities,while more K-strategist bacteria in the subsoil enhanced carbon utilization capacity,thereby increasing lignin phenols and lipids from plant residues in both soil layers.Meanwhile,higher Ca^(2+)concentrations in K.obovata sediments protected three residual carbons from further microbe decomposition.This study provides valuable insights into the molecular mechanisms of SOC sequestration mediated by microbial life strategies in mangrove ecosystems.展开更多
Mining activities have caused significant land degradation globally,emphasizing the need for effective restoration.Microbial inoculants offer a promising solution for sustainable remediation by enhancing soil nutrient...Mining activities have caused significant land degradation globally,emphasizing the need for effective restoration.Microbial inoculants offer a promising solution for sustainable remediation by enhancing soil nutrients,enzyme activities,and microbial communities to support plant growth.However,the mechanisms by which inoculants influence soil microbes and their relationship with plant growth require further investigation.Metagenomic sequencing was employed for this study,based on a one-year greenhouse experiment,to elucidate the effects of Bacillus thuringiensis NL-11 on the microbial functions of abandoned mine soils.Our findings revealed that the application of microbial inoculants significantly enhanced the soil total carbon(TC),total sulfur(TS),organic carbon(SOC),available phosphorus(AP),ammonium(NH4+),urease,arylsulfatase,phosphatase,β-1,4-glucosidase(BG),β-1,4-N-acetylglucosaminidase(NAG).Moreover,this led to substantial improvements in plant height,as well as aboveground and belowground biomass.Microbial inoculants impacted functional gene structures without altering diversity.The normalized abundance of genes related to the degradation of carbon and nitrogen,methane metabolism,and nitrogen fixation were observed to increase,as well as the functional genes related to phosphorus cycling.Significant correlations were found between nutrient cycling gene abundance and plant biomass.Partial Least Squares Path Model analysis showed that microbial inoculants not only directly influenced plant biomass but also indirectly affected the plant biomass through C cycle modifications.This study highlights the role of microbial inoculants in promoting plant growth and soil restoration by improving soil properties and enhancing normalized abundance of nutrient cycling gene,making them essential for the recovery of abandoned mine sites.展开更多
Carbon emissions from wastewater treatment contribute to global warming and have received widespread attention.It is necessary to seek low-carbon wastewater treatment technologies.Microbial fuel cells(MFC)and osmotic ...Carbon emissions from wastewater treatment contribute to global warming and have received widespread attention.It is necessary to seek low-carbon wastewater treatment technologies.Microbial fuel cells(MFC)and osmotic microbial fuel cells(Os MFC)are low-carbon technologies that enable both wastewater treatment and energy recovery.In this study,MFC and Os MFC were used to treat sulfamethoxazole(SMX)wastewater,and direct carbon emissions during operation was calculated.The highest SMX removal rate can reach about 40%.Simultaneously,the CH_(4)emission factor was significantly reduced to<6 g CO_(2)/kg of chemical oxygen demand.The accumulation of SMX-degrading bacteria competed with methanogens for carbon source utilization,leading to a significant decrease in the relative abundance of methanogens.It is hoped that this study can provide a sustainable approach to antibiotic wastewater treatment and promote the development of low-carbon wastewater treatment technologies.展开更多
Understanding the elevational patterns of soil microbial carbon(C)metabolic potentials is instrumental for predicting changes in soil organic C(SOC)stocks in the face of climate change.However,such patterns remain unc...Understanding the elevational patterns of soil microbial carbon(C)metabolic potentials is instrumental for predicting changes in soil organic C(SOC)stocks in the face of climate change.However,such patterns remain uncertain in arid mountain ecosystems,where climosequences are quite different from other ecosystems.To address this gap,this study investigated the distribution determinants of microbial communities,C cycling-related genes,and SOC fractions along an elevational gradient(1707–3548 m),with a mean annual precipitation(MAP)range of 38 to 344 mm,on the north slope of the central part of the Kunlun Mountains,China using a metagenomic approach.The results showed that elevation significantly influenced the α-diversity(Shannon index)and composition of microbial communities as well as the C cycling-related genes.The α-diversities of microbial taxa and C cycling-related genes linearly increased with the increase in MAP along the elevational gradient.The elevational patterns of the genes encoding glycoside hydrolases and glycosyl transferases(GTs)were mainly driven by soil electrical conductivity(EC),mean annual temperature(MAT),MAP,and plant diversity.Furthermore,mineral-associated organic C(MAOC),particulate organic C(POC),and their sum generally increased with elevation.However,the MAOC/POC ratio followed a unimodal pattern,suggesting greater stability of the SOC pool in the mid-elevation regions.This unimodal pattern was likely influenced by the abundances of Actinobacteria and the genes encoding GTs and carbohydrate esterases and the threshold effects of soil EC and MAT.In summary,our findings indicate that the distribution patterns of microbial communities and C cycling-related genes along the elevational gradient in an arid ecosystem are distinct from those in the regions with higher MAP,facilitating the prediction of climate change effects on SOC metabolism under more arid conditions.Soil salinity,plant diversity,precipitation,and temperature are the main regulatory factors of microbial C metabolism processes,and they potentially play a central role in mediating SOC pool stability.展开更多
Evaluating petroleum contamination risk and implementing remedial measures in agricultural soil rely on indicators such as soil metal(loid)s and microbiome alterations.However,the response of these indicators to petro...Evaluating petroleum contamination risk and implementing remedial measures in agricultural soil rely on indicators such as soil metal(loid)s and microbiome alterations.However,the response of these indicators to petroleum contamination remains under-investigated.The present study investigated the soil physicochemical features,metal(loid)s,microbial communities and networks,and phospholipid fatty acids(PLFAs)community structures in soil samples collected from long-(LC)and short-term(SC)petroleum-contaminated oil fields.The results showed that petroleum contamination increased the levels of soil total petroleum hydrocarbon,carbon,nitrogen,sulfur,phosphorus,calcium,copper,manganese,lead,and zinc,and decreased soil pH,microbial biomass,bacterial and fungal diversity.Petroleum led to a rise in the abundances of soil Proteobacteria,Ascomycota,Oleibacter,and Fusarium.Network analyses showed that the number of network links(Control vs.SC,LC=1181 vs.700,1021),nodes(Control vs.SC,LC=90 vs.71,83)and average degree(Control vs.SC,LC=26.244 vs.19.718,24.602)recovered as the duration of contamination increased.Petroleum contamination also reduced the concentration of soil PLFAs,especially bacterial.These results demonstrate that brief exposure to high levels of petroleum contamination alters the physicochemical characteristics of the soil as well as the composition of soil metal(loid)s andmicroorganisms,leading to a less diverse soilmicrobial network that is more susceptible to damage.Future research should focus on the culturable microbiome of soil under petroleum contamination to provide a theoretical basis for further remediation.展开更多
Over half of century,sanitary landfill was and is still the most economical treatment strategy for solid waste disposal,but the environmental risks associated with the leachate have brought attention of scientists for...Over half of century,sanitary landfill was and is still the most economical treatment strategy for solid waste disposal,but the environmental risks associated with the leachate have brought attention of scientists for its proper treatment to avoid surface and ground water deterioration.Most of the treatment technologies are energy-negative and cost intensive processes,which are unable to meet current environmental regulations.There are continuous demands of alternatives concomitant with positive energy and high effluent quality.Microbial fuel cells(MFCs)were launched in the last two decades as a potential treatment technology with bioelectricity generation accompanied with simultaneous carbon and nutrient removal.This study reviews capability and mechanisms of carbon,nitrogen and phosphorous removal from landfill leachate through MFC technology,as well as summarizes and discusses the recent advances of standalone and hybrid MFCs performances in landfill leachate(LFL)treatment.Recent improvements and synergetic effect of hybrid MFC technology upon the increasing of power densities,organic and nutrient removal,and future challenges were discussed in details.展开更多
Arsenic(As)methylation in soils affects the environmental behavior of As,excessive accumulation of dimethylarsenate(DMA)in rice plants leads to straighthead disease and a serious drop in crop yield.Understanding the m...Arsenic(As)methylation in soils affects the environmental behavior of As,excessive accumulation of dimethylarsenate(DMA)in rice plants leads to straighthead disease and a serious drop in crop yield.Understanding the mobility and transformation of methylated arsenic in redox-changing paddy fields is crucial for food security.Here,soils including unarsenic contaminated(N-As),low-arsenic(L-As),medium-arsenic(M-As),and high-arsenic(H-As)soils were incubated under continuous anoxic,continuous oxic,and consecutive anoxic/oxic treatments respectively,to profile arsenic methylating process and microbial species involved in the As cycle.Under anoxic-oxic(A-O)treatment,methylated arsenic was significantly increased once oxygen was introduced into the incubation system.The methylated arsenic concentrations were up to 2-24 times higher than those in anoxic(A),oxic(O),and oxic-anoxic(O-A)treatments,under which arsenic was methylated slightly and then decreased in all four As concentration soils.In fact,the most plentiful arsenite S-adenosylmethionine methyltransferase genes(arsM)contributed to the increase in As methylation.Proteobacteria(40.8%-62.4%),Firmicutes(3.5%-15.7%),and Desulfobacterota(5.3%-13.3%)were the major microorganisms related to this process.These microbial increasedmarkedly and played more important roles after oxygen was introduced,indicating that they were potential keystone microbial groups for As methylation in the alternating anoxic(flooding)and oxic(drainage)environment.The novel findings provided newinsights into the reoxidation-driven arsenic methylation processes and the model could be used for further risk estimation in periodically flooded paddy fields.展开更多
BACKGROUND Irritable bowel syndrome with predominant constipation(IBS-C)is a chronic gastrointestinal disorder that significantly impacts the quality of life of patients and currently lacks a definitive treatment.The ...BACKGROUND Irritable bowel syndrome with predominant constipation(IBS-C)is a chronic gastrointestinal disorder that significantly impacts the quality of life of patients and currently lacks a definitive treatment.The use of electroacupuncture(EA)has demonstrated clinical efficacy in treating IBS-C and the gut-brain axis modulation,though its mechanisms remain unclear.AIM To investigate gut-brain-microbiota axis alteration and EA-associated microbial changes in IBS-C patients and treatment responders.METHODS This study consisted of two phases.The first phase was a cross-sectional study recruiting sixteen IBS-C patients and 16 healthy controls.Baseline fecal samples were collected to assess gut microbiota profiles between the two groups.The second phase was an observational longitudinal study in which the 16 IBS-C patients underwent nine EA sessions over one month.Gut microbiota profiles and clinical outcomes were assessed post-treatment course and at a one-month follow-up.RESULTS IBS-C patients exhibited significant gut dysbiosis,as indicated by altered beta diversity compared to healthy controls.EA significantly improved clinical outcomes and gut dysbiosis,with sustained therapeutic effects and normalization of neurotransmitter-related metabolic pathways observed at one-month follow-up.Notably,the gut bacterium Senegalimassilia was positively associated with symptom improvement,suggesting its potential as a predictive biomarker of EA responsiveness.CONCLUSION These findings support the integration of EA into IBS-C management and highlight Senegalimassilia as a candidate microbial biomarker for treatment response.展开更多
Bioelectrochemical regulation has been proved to enhance the traditional anaerobic digestion(AD)of organic wastes.However,few investigations have explored whether it is possible to enhance the production of biomethane...Bioelectrochemical regulation has been proved to enhance the traditional anaerobic digestion(AD)of organic wastes.However,few investigations have explored whether it is possible to enhance the production of biomethane from raw corn stover(CS).A single-chamber microbial electrolysis cell(MEC)was incorporated with an AD to form a new system(MEC-AD)with aiming at more efficient bioconversion of CS to biomethane.The performance and microbiological characteristics of MEC-AD was investigated,and compared with conventional AD,which were inoculated with original inoculum(UAD)and electrically domesticated inoculum(EAD),respectively.The results showed that MEC-AD achieved the highest CH_(4)yield of 239.13 ml·g^(-1)volatile solids(VS),which was 29.28%and 12.44%higher than those of UAD and EAD,respectively.MEC-AD also achieved higher substance conversion rates of 73.24%VS,91.16%cellulose,and 77.24%hemicellulose,respectively.The community characteristics of microorganisms revealed that the relative abundance and interactions of functional microorganisms in MEC-AD were obviously different from UAD and EAD.In MEC-AD,Electroactive bacteria(Sedimentibacter)with electrotrophic methanogens(Methanosarcina and Methanosaeta)in anodic biofilms established electrotrophic methanogenesis through direct interspecies electron transfer(DIET).The process of methanotrophic methanogenesis was facilitated by the interactions between fermentative acid-producing bacteria(FABs),syntrophic organic acid oxidation bacteria(SOBs),and methylotrophic methanogens(Methyl-HMs)in MEC-AD suspensions.Efficient synergistic interactions between these functional microorganisms improved the performance of MEC-AD in converting CS to produce biomethane.The study could provide an effective means for achieving higher AD biomethane production from raw CS.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.32160172)the Key Science-Technology Project of Inner Mongolia(2023KYPT0010)+1 种基金the Natural Science Foundation of Inner Mongolia Autonomous Region of China(Grant No.2025QN03006)the 2023 Inner Mongolia Public Institution High-level Talent Introduction Scientific Research Support Project.
文摘This study establishes and validates a method for the precise quantification of aquatic microbial loads using microbial diversity absolute quantitative sequencing.By adding synthetic spike-in DNA to water samples from the Dahei River prior to DNA extraction and 16S rRNA gene sequencing,it generates standard curves to convert sequencing data into absolute microbial copy numbers.The method,which is proved highly accurate(R^(2)>0.99),reveals a clear contrast between the river sites:the upstream community has not only a significantly higher total microbial load but also a completely different makeup of species compared to the downstream site.This approach effectively overcomes the limitations of relative abundance analysis,providing a powerful tool for environmental monitoring,and proposes key steps for future standardization to ensure data comparability and integration.
基金funded by the Beef Cattle Research Council Cluster(FDE.18.21C)Natural Sciences and Engineering Research Council of Canada(NSERC)Discovery,NSERC Canadian Research Chair(Tier 1)program+2 种基金NSERC Alliance program(ALLRP 588541‐23)Foundation for Food&Agriculture Research Greener Cattle Initiative(Award ID 22‐000373)DSM Nutritional Products,Kaiseraugst,Switzerland。
文摘Background The enteric methane inhibitor 3-nitrooxypropanol(3-NOP)inhibits the key enzyme in ruminal methanogenesis,but whether short-term(ST)and long-term(LT)dietary supplementation has similar effects on rumen microbiota in beef cattle and how microbes change after 3-NOP withdrawal have not been studied.This study investigated changes in rumen bacteria,archaea,and protozoa after ST and LT dietary supplementation and removal of 3-NOP using metataxonomic analysis.Results A total of 143 rumen samples were collected from two beef cattle studies with 3-NOP supplementation.The ST study(95 samples)used eight ruminally cannulated beef cattle in a 4×4 Latin square design with four 28-d of 3-NOP treatments[mg/kg of dry matter(DM)]:control:0,low:53,med:161,and high:345.The LT study(48 samples)was a completely randomized design with two 3-NOP treatments[control:0,and high:280 mg/kg of DM)fed for 112-d followed by a 16-d withdrawal(without 3-NOP).Bacterial and archaeal communities were significantly affected by 3-NOP supplementation but limited effects on protozoal communities were observed.Under ST supplementation,the relative abundances of Prevotella,Methanobrevibacter(Mbb.)ruminantium,Methanosphaera sp.ISO3-F5,and Entodinium were increased(Q<0.05),whereas those of Mbb.gottschalkii and Epidinium were decreased(Q<0.05)with 3-NOP supplementation.In LT study,relative abundances of Mbb.ruminantium,and Methanosphaera sp.Group5 were increased(Q<0.05),while those of Saccharofermentans and Mbb.gottschalkii were decreased(Q<0.05)with 3-NOP supplementation.Comparison between 3-NOP supplementation and the withdrawal revealed increased relative abundances of Clostridia UCG-014 and Oscillospiraceae NK4A214 group and decreased those of Eubacterium nodatum group and Methanosphaera sp.Group5(P<0.05)after 3-NOP withdrawal.Further comparison of rumen microbiota between control and 3-NOP withdrawal showed significantly higher(P=0.029)relative abundances of Eggerthellaceae DNF00809,p-1088-a5 gut group,and Family XII UCG-001 in control group while no significant differences were detected for archaea and protozoa.Microbial network analysis revealed that microbial interactions differed by both 3-NOP dose and durations.Conclusions Both ST and LT supplementation affected overall rumen microbial profile,with individual microbial groups responded to 3-NOP supplementation differently.After 3-NOP withdrawal,not all microbes showed recovery,indicating that the 3-NOP driven shifts were only partially reversible.These findings provide an understanding of the effects of 3-NOP on rumen microbial communities and their adaptability to methane mitigation strategies.
基金supported by the National Science and Technology Major Program for Noncommunicable Chronic Diseases(2023ZD0503500)the National Natural Science Foundation of China(82030102,12126602,91857118)+1 种基金the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(2021-I2M-1-010,2019-I2M-2-003)the National High Level Hospital Clinical Research Funding(2022-GSP-GG-1,2022-GSP-GG-2)。
文摘Objective Evidence suggests that depleted gut microbialα-diversity is associated with hypertension;however,whether metabolic markers affect this relationship remains unknown.We aimed to determine the potential metabolites mediating the associations ofα-diversity with blood pressure(BP)and BP variability(BPV).Methods Metagenomics and plasma targeted metabolomics were conducted on 523 Chinese participants from the MetaSalt study.The 24-hour,daytime,and nighttime BP and BPV were calculated based on ambulatory BP measurements.Linear mixed models were used to characterize the relationships betweenα-diversity(Shannon and Chao1 index)and BP indices.Mediation analyses were performed to assess the contribution of metabolites to the observed associations.The influence of key metabolites on hypertension was further evaluated in a prospective cohort of 2,169 participants.Results Gut microbial richness(Chao1)was negatively associated with 24-hour systolic BP,daytime systolic BP,daytime diastolic BP,24-hour systolic BPV,and nighttime systolic BPV(P<0.05).Moreover,26 metabolites were strongly associated with richness(Bonferroni P<0.05).Among them,four key metabolites(imidazole propionate,2-hydroxy-3-methylbutyric acid,homovanillic acid,and hydrocinnamic acid)mediated the associations between richness and BP indices(proportions of mediating effects:14.1%–67.4%).These key metabolites were also associated with hypertension in the prospective cohort.For example,each 1-standard deviation unit increase in hydrocinnamic acid significantly reduced the risk of prevalent(OR[95%CI]=0.90[0.82,0.99];P=0.03)and incident hypertension(HR[95%CI]=0.83[0.71,0.96];P=0.01).Conclusion Our results suggest that gut microbial richness correlates with lower BP and BPV,and that certain metabolites mediate these associations.These findings provide novel insights into the pathogenesis and prevention of hypertension.
基金Under the auspices of the National Natural Science Foundation of China(No.42430511,U20A2083)the National Key Research and Development Program of China(No.2022YFF1300900)the Science and Technology Development Program of Jilin Province(No.20210509037RQ,20230101348JC)。
文摘Elevation patterns and assembly processes of soil microbial community structures are essential for understanding biogeo-chemical processes in mountain systems.Differences in soil properties caused by elevation gradients can regulate the spatial distribu-tion and network complexity of the community structure.To explore the variations in soil microbial community structures and their as-sembly mechanisms across different elevations of the Changbai Mountains,as well as their responses to environmental factors,we col-lected microbial samples along an elevational gradient(seven elevations containing four vegetation zones)on the western slope of the Changbai Mountains using the method of metagenomic sequencing.The results showed a significant difference(P<0.05)for the Chao1 index across different elevations,but no significant difference was observed for the Shannon and Simpson indices.With increasing elev-ation,the number of nodes and links in the microbial network gradually decreased.Acidobacteria were highly connected to many nodes.The microbial communities indicated a significant distance-decay relationship(P<0.001)and were affected more by stochastic pro-cesses along the elevation gradient.The results of the Structural Equation Model(SEM)showed that elevation had direct significant ef-fect on carbon(C,P<0.01),nitrogen(N,P<0.01),and phosphorus(P,P<0.05)and weak negative effect on their ecological stoi-chiometry.Elevation was one of the major variables contributing to microbial network topology.The contribution of C and N to micro-bial network complexity was higher than that of P.Our study provides valuable insights into the responses of soil microbial communit-ies to elevation variations.
基金supported by the National Natural Science Foundation of China(No.52371056)the Liaoning Provincial Youth Science Fund Project,China(Category B,No.2025JH6/101000010)the Guangdong Basic and Applied Basic Research Foundation,China(No.2024A1515240055).
文摘Microbial contamination and the resulting corrosion in aircraft fuel system pose a serious threat to flight safety.Revealing the corrosion behavior and mechanism of fuel-degrading microorganisms on tank materials is crucial for developing effective mitigation strategies.In this study,the corrosion mechanisms of two representative hydrocarbon-degrading bacteria,Alcanivorax dieselolei and Microbacterium oxydans,toward AA7075 aluminum alloy,were systematically investigated.A combination of biofilm characterization,electrochemical testing,and surface/corrosion product characterization was employed.Both strains markedly accelerated the corrosion of AA7075,as evidence by the progressive decrease in polarization resistance and the pronounced rightward shift of the potentiodynamic polarization curves.Moreover,the difference between the pitting potential(E_(pit))and the corrosion potential(E_(corr))(ΔE=E_(pit)‒E_(corr))decreased due to microbial activities,indicating a pronounced tendency toward accelerated pitting corrosion.Corrosion morphology analysis revealed that both microbes promoted localized pitting corrosion.Furthermore,analysis of aviation kerosene composition indicated that both bacteria accelerated the degradation of C8 and C9 alkanes.These findings highlight the multiple threats of microbial contamination,material degradation,and fuel quality deterioration in fuel systems and underscore the need for targeted protection strategies for marine aviation operations.
基金supported by the National Natural Science Foundation of China(32330105 and 32301247)National Key R&D Program of China(2023YFD1801100)。
文摘Background An imbalance in the rumen microbiota caused by high-concentrate diets(HCD)is a significant endogenous trigger of mastitis.However,the underlying mechanisms remain largely unknown.Microbial extracellular vesicles(mEVs)are critical mediators of microbe-host communication.However,the role of mEVs in rumen microbiota-mediated mastitis has not yet been reported.In this study,we used an HCD-induced rumen microbiota dysbiosis model to investigate the role of mEVs-derived from rumen microbiota in the pathogenesis of mastitis.Results Our results indicate that HCD leads to mastitis and systemic inflammation.Meanwhile,HCD-fed goats exhibited substantial rumen microbiota dysbiosis and the disruption of the rumen barrier.Transplanting rumen microbiota from HCD goats into mice induced both mastitis and systemic inflammation in the recipients.Specifically,HCD increases the production of mEVs carrying microbial DNA,which can translocate across the compromised rumen barrier to the mammary gland,triggering a mammary inflammatory response via activation of the cGAS-STING-NF-κB/NLRP3 pathway.Furthermore,treating mice with mEVs isolated from the rumen fluid of HCD goats directly induced mastitis,whereas depletion of microbial DNA attenuated mEVs-induced mastitis.Conclusion Our findings suggest that HCD induces rumen microbiota dysbiosis and impairs rumen barrier function.This dysfunction leads to an increase in microbial DNA-containing mEVs,which subsequently leak into the mammary gland.Once there,these mEVs activate the cGAS-STING-NF-κB/NLRP3 signaling pathway,ultimately inducing mastitis.This study provides a new perspective on the“rumen microbiota-mammary gland axis”and enhances the understanding of the pathogenesis of mastitis.
基金supported by the National Natural Science Foundation of China(No.42377083)the Natural Science Foundation of Sichuan Province,China(No.2025 ZNSFSC0433).
文摘In this work,ofloxacin(OFL),a kind of frequently detected antibiotic in groundwater,was selected to explore its impact(at ng/L-μg/L-level)on denitrification performance in an autotrophic denitrification system driven by pyrite/sulfur(FeS2/S0).Results showed that OFL restrained nitrate removal efficiency,and the inhibition degree was positively related to the concentration of OFL.After being exposed to increased OFL(200 ng/L-100μg/L)for 69 days,higher inhibition of electron transport activity(ETSA),enzyme activities of nitrate reductase(NAR),and nitrite reductase(NIR)were acquired.Meanwhile,the extracellular protein(PN)content of sludge samples was remarkably stimulated by OFL to resist the augmented toxicity.OFL contributed to increased microbial diversity and sulfur/sulfide oxidation functional genes in ng/L-level bioreactors,whereas led to a decline inμg/L level experiments.With OFL at concentrations of 200 ng/L and 100μg/L,the whole expression of 10 key denitrification functional genes was depressed,and the higher the OFL concentration,the lower the expression level.However,no significant proliferation of antibiotic resistance genes(ARGs)either in 200 ng/L-OFL or 100μg/L-OFL groups was observed.Two-factor correlation analysis results indicated that Thiobacillus,Anaerolineae,Anaerolineales,and Nitrospirae might be the main hosts of existing ARGs in this system.
基金the Department of Science and Technology(DST)-India for providing a departmental grant to the Department of Biochemistry,Central University of Punjab,Bathinda,India,in the form of a DST-Fund for Improvement of S&T Infrastructure(FIST)grant。
文摘Microplastics (MPs), fluoride (FR), and fungicide mancozeb (MZ) are common contaminants in soil. However, there is no information about the combined impacts of MPs, FR, and MZ on tomato plant growth features in the literature. This study aimed to investigate the effects of combined application of MPs, FR, and MZ (both analytical grade and commercial) on the growth and development of tomato plants and metagenomics of rhizosphere soil. A pot experiment was set up in an artificial greenhouse with two sets of treatments. One set was the combined application of MPs, FR, and analytical grade MZ (B2) and a control without the application of MPs, FR, and MZ (W2), and the other set was the combined application of MPs, FR, and commercial MZ (B3) and a control without the application of MPs, FR, and MZ (W3). No detrimental effects of MPs, FR, and MZ were detected on the growth parameters of tomato plants, including the number of leaves and chlorophyll concentration. However, tomato roots showed knot and nodulation-type structures, and metabolomic profiling revealed that combined exposure to MPs, FR, and MZ profoundly reprogrammed the primary metabolism in tomato roots, with marked alterations in carbohydrate and amino acid pathways. Metagenome whole genome sequencing showed that the B2 and B3 treatments profoundly affected soil microbial community composition, diversity, gene abundances, and functional gene variations compared to W2 and W3. Proteobacteria became the dominating phylum in B2 and B3, causing a significant shift in the microbiome. Its abundance soared to 66.7% in B2 and 75.4% in B3, compared to only 35.9% in W2 and 28.9% in W3. On the other hand, Actinobacteria decreased significantly from 55.6% in W2 and 63.8% in W3 to 18.1% in B2 and 9.6% in B3. This study highlights the microbial shifts due to combined application of MPs, FR, and MZ, providing evidence for understanding their environmental risks.
基金supported by the National Natural Science Foundation of China(No.42007428)the National Forage Industry Technology System Program of China(No.CARS34)+1 种基金the Key Research and Development Program of Shaanxi,China(No.2022SF-285)Shaanxi Province Forestry Science and Technology Innovation Program,China(No.SXLK2022-02-14)。
文摘Effective vegetation reconstruction plays a vital role in the restoration of desert ecosystems.However,in reconstruction of different vegetation types,the community characteristics,assembly processes,and functions of different soil microbial taxa under environmental changes are still disputed,which limits the understanding of the sustainability of desert restoration.Hence,we investigated the soil microbial community characteristics and functional attributes of grassland desert(GD),desert steppe(DS),typical steppe(TS),and artificial forest(AF)in the Mu Us Desert,China.Our findings confirmed the geographical conservation of soil microbial composition but highlighted decreased microbial diversity in TS.Meanwhile,the abundance of rare taxa and microbial community stability in TS improved.Heterogeneous and homogeneous selection determined the assembly of rare and abundant bacterial taxa,respectively,with both being significantly influenced by soil moisture.In contrast,fungal communities displayed stochastic processes and exhibited sensitivity to soil nutrient conditions.Furthermore,our investigation revealed a noteworthy augmentation in bacterial metabolic functionality in TS,aligning with improved vegetation restoration and the assemblage of abundant bacterial taxa.However,within nutrient-limited soils(GD,DS,and AF),the assembly dynamics of rare fungal taxa assumed a prominent role in augmenting their metabolic capacity and adaptability to desert ecosystems.These results highlighted the variations in the assembly processes and metabolic functions of soil microorganisms during vegetation reestablishment and provided corresponding theoretical support for anthropogenic revegetation of desert ecosystems.
基金supported by the National Natural Science Foundation of China(No.31860023)the Light of West China Program of Chinese Academic of Sciences(No.[2019]90)+1 种基金the Basic Research Fund of Guangxi Academy of Sciences,China(No.CQZ-D-1904)the Fundamental Research Fund of the Guangxi Institute of Botany,China(Guizhiye Nos.24010 and 24012).
文摘Soil nitrogen(N)cycling is one of the most critical biogeochemical cycles,and N cycling-related microorganisms are the primary driving force behind N cycling in natural environments.The large karst sinkholes in China,known as Tiankengs,harbor abundant unique biological resources due to their particular environmental conditions.However,N cycling-related microorganisms in Tiankeng soils and their connection to ecosystem processes remain poorly studied.In this study,we investigated the distribution patterns and genomic diversity of N cycling-related microorganisms both inside and outside the Luohun cave Tiankeng in Guizhou,China,utilizing high-throughput sequencing and other techniques.The results indicated that the diversities and abundances of denitrifying bacteria,ammonia-oxidizing bacteria,and ammonia-oxidizing archaea communities inside the Tiankeng were higher than those outside the Tiankeng;however,the microbial network relationships were more fragile inside the Tiankeng.The most abundant species of denitrifying bacteria,ammonia-oxidizing bacteria,and ammonia-oxidizing archaea inside the Tiankeng were unclassified_p_Proteobacteria(47.8%),unclassified_k_norank(AOB,OTU121,37.3%),and unclassified_g_norank_f_norank_o_norank_c_environmental_samples(55.7%),respectively;outside the Tiankeng,they were unclassified_k_norank_d_bacteria(54.5%),unclassified_k_norank(AOB,OTU121,48.1%),and unclassified_k_norank(AOA,OTU70,49.6%),respectively.Additionally,the N content inside the Tiankeng was significantly lower(P<0.05)under the influence of these N cycling-related microorganisms,whereas the nutrient contents were higher than that outside the Tiankeng.To the best of our knowledge,this is the first report on the crucial microbial distribution patterns driving N cycling in karst Tiankengs and provides new insights into the structure and potential functions of N cycling-related microorganisms in the unique ecological environment of fragile Tiankeng ecosystems.
文摘This study was conducted at the scientific center of Brazzaville. The objective was to assess the microbial characteristics and enzymes activities in the rhizosphere soil of Cajanus cajan and Milletia lauurentii. These plants have great importance in food and forestry. Microbial diversity management in the rhizosphere is the key for sustainable crop production or forest durability. DNA metagenomic sequencing was used to analyze the whole bacterial diversity, the microbial biomass was determinate by the fumigation-extraction method and the enzymes by the p-nitrophenol-β-D-glucoside for β-glucosidase, the p-nitrophenyl-N-acetyl-β-D-glucosaminide for β-Glucosaminidase. Dehydrogenase and acid phosphatase were quantified using 2,3,5-tryphenyl tetrazolium chloride and p-nitophenylphosphate respectively. The results show that, in Cajanus cajan culturable bacteria genera were mainly Acidobacterium, Skermanella, Rhodoplanes, Bacillus, Chloroflexus, Steroidobacter, Sphingomonas and Bradyrhizobium while in Milletia laurentii: Rhodoplanes, Bradyrhizobium, Bacillus, Sphingobacterium, Acidobacterium, Mesorhizobium, Nitrospira were the principal genera. In the two rhizosphere soils investigated, the uncultured bacteria exhibited relatively higher abundance, often for the same genera, than culturable bacteria. Metagenomic studies have revealed more bacterial diversity in each compared to when culturable bacteria were taken into account alone. The MBC and MBN were higher in the rhizosphere of Milletia than in rhizosphere of Cajanus. The same trend was observed with the enzyme activities. PCA of culturable and NMDS of unculturable soil bacteria genera shows that factors mainly involved in the carbon cycle such as MBC, members of the microbial community i.e. Acidobacterium, Skermanella, Chloroflexus, sand, C, β-glucosaminidase and dehydrogenase, were strongly correlated with Cajanus cajan. On the other hand, the MBN, Mesorhizobium, Bradyrhizobium, Burkholderia, Nitrospira, Nitratireductor, N, NH4, β-glucosidase and acid phosphatase involved in the N cycling, silt and clay were predominantly founded in the rhizosphere soil of Milletia laurentii. This study showed that metagenomic sequencing could improve the assessment of the microbial diversity structure of the rhizosphere.
基金supported by grants from the National Natural Science Foundation of China(Nos.42076117 and 32160051)the Guangdong Basic and Applied Basic Research Foundation(Nos.2023A1515012772,2024A1515011721,and 2024A1515012249).
文摘Soil organic carbon(SOC)plays a crucial role in mangrove blue carbon formation,yet the differences in microbemediated underlying SOC sequestration between introduced and native mangroves remain unclear.Here,we compared the SOC pool,including recalcitrant organic carbon(ROC)and labile carbon pools,as well as three residual carbon sources(amino sugars,lignin phenols,and lipids)in sediments between mangroves of introduced Sonneratia apetala and native Kandelia obovata,and further connected them with microbial life strategies and C metabolism capability.The results showed that SOC accumulation in S.apetala(SA)sediment was about 30%-50% of that in K.obovata(KO)sediment.ROC was the dominant form of SOC in long-term sequestration(76%-83%),while lignin phenols,amino sugars,and lipids were important sources of ROC.In S.apetala sediments,the ROC content was positively correlated with amino sugars,resulting from the more r-strategist microbes that can rapidly convert plant-derived carbon into microbial biomass,which is subsequently transformed into microbial necromass.In contrast,in K.obovata sediments,ROC content showed a stronger positive correlation with the concentrations of lignin phenols and lipids.More K-strategist fungi in the topsoil of K.obovata increased enzyme activities,while more K-strategist bacteria in the subsoil enhanced carbon utilization capacity,thereby increasing lignin phenols and lipids from plant residues in both soil layers.Meanwhile,higher Ca^(2+)concentrations in K.obovata sediments protected three residual carbons from further microbe decomposition.This study provides valuable insights into the molecular mechanisms of SOC sequestration mediated by microbial life strategies in mangrove ecosystems.
基金supported by the Jiangsu Science and Technology Plan Project(No.BE2022420)the Innovation and Promotion of Forestry Science and Technology Program of Jiangsu Province(No.LYKJ[2021]30)+2 种基金the Scientific Research Project of Baishanzu National Park(No.2021ZDLY01)the Ningxia key research and development plan(No.2021BEG02010)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
文摘Mining activities have caused significant land degradation globally,emphasizing the need for effective restoration.Microbial inoculants offer a promising solution for sustainable remediation by enhancing soil nutrients,enzyme activities,and microbial communities to support plant growth.However,the mechanisms by which inoculants influence soil microbes and their relationship with plant growth require further investigation.Metagenomic sequencing was employed for this study,based on a one-year greenhouse experiment,to elucidate the effects of Bacillus thuringiensis NL-11 on the microbial functions of abandoned mine soils.Our findings revealed that the application of microbial inoculants significantly enhanced the soil total carbon(TC),total sulfur(TS),organic carbon(SOC),available phosphorus(AP),ammonium(NH4+),urease,arylsulfatase,phosphatase,β-1,4-glucosidase(BG),β-1,4-N-acetylglucosaminidase(NAG).Moreover,this led to substantial improvements in plant height,as well as aboveground and belowground biomass.Microbial inoculants impacted functional gene structures without altering diversity.The normalized abundance of genes related to the degradation of carbon and nitrogen,methane metabolism,and nitrogen fixation were observed to increase,as well as the functional genes related to phosphorus cycling.Significant correlations were found between nutrient cycling gene abundance and plant biomass.Partial Least Squares Path Model analysis showed that microbial inoculants not only directly influenced plant biomass but also indirectly affected the plant biomass through C cycle modifications.This study highlights the role of microbial inoculants in promoting plant growth and soil restoration by improving soil properties and enhancing normalized abundance of nutrient cycling gene,making them essential for the recovery of abandoned mine sites.
基金the Fundamental Research Funds for Central Public Research Institutes of China(No.2022YSKY14)the Fundamental Research Funds for the Central Publicinterest Scientific Institution(No.2023YSKY-07)。
文摘Carbon emissions from wastewater treatment contribute to global warming and have received widespread attention.It is necessary to seek low-carbon wastewater treatment technologies.Microbial fuel cells(MFC)and osmotic microbial fuel cells(Os MFC)are low-carbon technologies that enable both wastewater treatment and energy recovery.In this study,MFC and Os MFC were used to treat sulfamethoxazole(SMX)wastewater,and direct carbon emissions during operation was calculated.The highest SMX removal rate can reach about 40%.Simultaneously,the CH_(4)emission factor was significantly reduced to<6 g CO_(2)/kg of chemical oxygen demand.The accumulation of SMX-degrading bacteria competed with methanogens for carbon source utilization,leading to a significant decrease in the relative abundance of methanogens.It is hoped that this study can provide a sustainable approach to antibiotic wastewater treatment and promote the development of low-carbon wastewater treatment technologies.
基金sponsored by the Natural Science Foundation of Xinjiang Uygur Autonomous Region,China(No.2022D01B213)the Key Scientific and Technological Research Projects in the Xinjiang Production and Construction Corps,China(No.2023AB017-02)+1 种基金the West Light Foundation for Young Scholar of Chinese Academy of Sciences(No.2021-XBQNXZ-018)the National Key Research and Development Program of China(No.2022YFF1302504)。
文摘Understanding the elevational patterns of soil microbial carbon(C)metabolic potentials is instrumental for predicting changes in soil organic C(SOC)stocks in the face of climate change.However,such patterns remain uncertain in arid mountain ecosystems,where climosequences are quite different from other ecosystems.To address this gap,this study investigated the distribution determinants of microbial communities,C cycling-related genes,and SOC fractions along an elevational gradient(1707–3548 m),with a mean annual precipitation(MAP)range of 38 to 344 mm,on the north slope of the central part of the Kunlun Mountains,China using a metagenomic approach.The results showed that elevation significantly influenced the α-diversity(Shannon index)and composition of microbial communities as well as the C cycling-related genes.The α-diversities of microbial taxa and C cycling-related genes linearly increased with the increase in MAP along the elevational gradient.The elevational patterns of the genes encoding glycoside hydrolases and glycosyl transferases(GTs)were mainly driven by soil electrical conductivity(EC),mean annual temperature(MAT),MAP,and plant diversity.Furthermore,mineral-associated organic C(MAOC),particulate organic C(POC),and their sum generally increased with elevation.However,the MAOC/POC ratio followed a unimodal pattern,suggesting greater stability of the SOC pool in the mid-elevation regions.This unimodal pattern was likely influenced by the abundances of Actinobacteria and the genes encoding GTs and carbohydrate esterases and the threshold effects of soil EC and MAT.In summary,our findings indicate that the distribution patterns of microbial communities and C cycling-related genes along the elevational gradient in an arid ecosystem are distinct from those in the regions with higher MAP,facilitating the prediction of climate change effects on SOC metabolism under more arid conditions.Soil salinity,plant diversity,precipitation,and temperature are the main regulatory factors of microbial C metabolism processes,and they potentially play a central role in mediating SOC pool stability.
基金supported by Guangxi Key Research and Development Program(No.AB24010136)the Pre-project from Guangxi Bureau of Geology and Mineral Exploration and Development(No.2024051)Guangxi Geochemistry and Environmental Restoration and Management Research Talent Highland.
文摘Evaluating petroleum contamination risk and implementing remedial measures in agricultural soil rely on indicators such as soil metal(loid)s and microbiome alterations.However,the response of these indicators to petroleum contamination remains under-investigated.The present study investigated the soil physicochemical features,metal(loid)s,microbial communities and networks,and phospholipid fatty acids(PLFAs)community structures in soil samples collected from long-(LC)and short-term(SC)petroleum-contaminated oil fields.The results showed that petroleum contamination increased the levels of soil total petroleum hydrocarbon,carbon,nitrogen,sulfur,phosphorus,calcium,copper,manganese,lead,and zinc,and decreased soil pH,microbial biomass,bacterial and fungal diversity.Petroleum led to a rise in the abundances of soil Proteobacteria,Ascomycota,Oleibacter,and Fusarium.Network analyses showed that the number of network links(Control vs.SC,LC=1181 vs.700,1021),nodes(Control vs.SC,LC=90 vs.71,83)and average degree(Control vs.SC,LC=26.244 vs.19.718,24.602)recovered as the duration of contamination increased.Petroleum contamination also reduced the concentration of soil PLFAs,especially bacterial.These results demonstrate that brief exposure to high levels of petroleum contamination alters the physicochemical characteristics of the soil as well as the composition of soil metal(loid)s andmicroorganisms,leading to a less diverse soilmicrobial network that is more susceptible to damage.Future research should focus on the culturable microbiome of soil under petroleum contamination to provide a theoretical basis for further remediation.
基金supported by the National Key Research and Development Program of China (No. 2018YFD1100604)the China Scholarship Council grant (CSC No. 2018GBJ008465)。
文摘Over half of century,sanitary landfill was and is still the most economical treatment strategy for solid waste disposal,but the environmental risks associated with the leachate have brought attention of scientists for its proper treatment to avoid surface and ground water deterioration.Most of the treatment technologies are energy-negative and cost intensive processes,which are unable to meet current environmental regulations.There are continuous demands of alternatives concomitant with positive energy and high effluent quality.Microbial fuel cells(MFCs)were launched in the last two decades as a potential treatment technology with bioelectricity generation accompanied with simultaneous carbon and nutrient removal.This study reviews capability and mechanisms of carbon,nitrogen and phosphorous removal from landfill leachate through MFC technology,as well as summarizes and discusses the recent advances of standalone and hybrid MFCs performances in landfill leachate(LFL)treatment.Recent improvements and synergetic effect of hybrid MFC technology upon the increasing of power densities,organic and nutrient removal,and future challenges were discussed in details.
基金supported by the Shandong Province Natural Science Foundation of Major Basic Research Program (No.ZR2020ZD34)the Key Projects of the National Natural Science Foundation of China (No.42230706)+3 种基金the National Natural Science Foundation of China (No.42307164)the China Postdoctoral Science Foundation (Nos.2023TQ0191 and 2023M732060)the Shandong Postdoctoral Science Foundation (No.SDBX2023041)and the Qingdao Postdoctoral Science Foundation (No.QDBSH20230202052).
文摘Arsenic(As)methylation in soils affects the environmental behavior of As,excessive accumulation of dimethylarsenate(DMA)in rice plants leads to straighthead disease and a serious drop in crop yield.Understanding the mobility and transformation of methylated arsenic in redox-changing paddy fields is crucial for food security.Here,soils including unarsenic contaminated(N-As),low-arsenic(L-As),medium-arsenic(M-As),and high-arsenic(H-As)soils were incubated under continuous anoxic,continuous oxic,and consecutive anoxic/oxic treatments respectively,to profile arsenic methylating process and microbial species involved in the As cycle.Under anoxic-oxic(A-O)treatment,methylated arsenic was significantly increased once oxygen was introduced into the incubation system.The methylated arsenic concentrations were up to 2-24 times higher than those in anoxic(A),oxic(O),and oxic-anoxic(O-A)treatments,under which arsenic was methylated slightly and then decreased in all four As concentration soils.In fact,the most plentiful arsenite S-adenosylmethionine methyltransferase genes(arsM)contributed to the increase in As methylation.Proteobacteria(40.8%-62.4%),Firmicutes(3.5%-15.7%),and Desulfobacterota(5.3%-13.3%)were the major microorganisms related to this process.These microbial increasedmarkedly and played more important roles after oxygen was introduced,indicating that they were potential keystone microbial groups for As methylation in the alternating anoxic(flooding)and oxic(drainage)environment.The novel findings provided newinsights into the reoxidation-driven arsenic methylation processes and the model could be used for further risk estimation in periodically flooded paddy fields.
文摘BACKGROUND Irritable bowel syndrome with predominant constipation(IBS-C)is a chronic gastrointestinal disorder that significantly impacts the quality of life of patients and currently lacks a definitive treatment.The use of electroacupuncture(EA)has demonstrated clinical efficacy in treating IBS-C and the gut-brain axis modulation,though its mechanisms remain unclear.AIM To investigate gut-brain-microbiota axis alteration and EA-associated microbial changes in IBS-C patients and treatment responders.METHODS This study consisted of two phases.The first phase was a cross-sectional study recruiting sixteen IBS-C patients and 16 healthy controls.Baseline fecal samples were collected to assess gut microbiota profiles between the two groups.The second phase was an observational longitudinal study in which the 16 IBS-C patients underwent nine EA sessions over one month.Gut microbiota profiles and clinical outcomes were assessed post-treatment course and at a one-month follow-up.RESULTS IBS-C patients exhibited significant gut dysbiosis,as indicated by altered beta diversity compared to healthy controls.EA significantly improved clinical outcomes and gut dysbiosis,with sustained therapeutic effects and normalization of neurotransmitter-related metabolic pathways observed at one-month follow-up.Notably,the gut bacterium Senegalimassilia was positively associated with symptom improvement,suggesting its potential as a predictive biomarker of EA responsiveness.CONCLUSION These findings support the integration of EA into IBS-C management and highlight Senegalimassilia as a candidate microbial biomarker for treatment response.
基金supports from the Fundamental Research Funds for the Central Universities(NO.JD2402).
文摘Bioelectrochemical regulation has been proved to enhance the traditional anaerobic digestion(AD)of organic wastes.However,few investigations have explored whether it is possible to enhance the production of biomethane from raw corn stover(CS).A single-chamber microbial electrolysis cell(MEC)was incorporated with an AD to form a new system(MEC-AD)with aiming at more efficient bioconversion of CS to biomethane.The performance and microbiological characteristics of MEC-AD was investigated,and compared with conventional AD,which were inoculated with original inoculum(UAD)and electrically domesticated inoculum(EAD),respectively.The results showed that MEC-AD achieved the highest CH_(4)yield of 239.13 ml·g^(-1)volatile solids(VS),which was 29.28%and 12.44%higher than those of UAD and EAD,respectively.MEC-AD also achieved higher substance conversion rates of 73.24%VS,91.16%cellulose,and 77.24%hemicellulose,respectively.The community characteristics of microorganisms revealed that the relative abundance and interactions of functional microorganisms in MEC-AD were obviously different from UAD and EAD.In MEC-AD,Electroactive bacteria(Sedimentibacter)with electrotrophic methanogens(Methanosarcina and Methanosaeta)in anodic biofilms established electrotrophic methanogenesis through direct interspecies electron transfer(DIET).The process of methanotrophic methanogenesis was facilitated by the interactions between fermentative acid-producing bacteria(FABs),syntrophic organic acid oxidation bacteria(SOBs),and methylotrophic methanogens(Methyl-HMs)in MEC-AD suspensions.Efficient synergistic interactions between these functional microorganisms improved the performance of MEC-AD in converting CS to produce biomethane.The study could provide an effective means for achieving higher AD biomethane production from raw CS.
