Microorganisms carrying cbbL,pmoA and coxL genes play crucial roles in regulating soil-atmosphere exchanges of carbon trace gases(CO_(2),CH_(4),and CO).However,the geographical distribution patterns of these functiona...Microorganisms carrying cbbL,pmoA and coxL genes play crucial roles in regulating soil-atmosphere exchanges of carbon trace gases(CO_(2),CH_(4),and CO).However,the geographical distribution patterns of these functional genes in agricultural ecosystems and their environmental drivers remain poorly understood.Here,we surveyed agricultural soils across four climate zones(tropical,subtropical,warm temperate,and mid-temperate)in eastern China to quantify the abundances of CO_(2)-assimilating bacteria(cbbL gene),methanotrophs(pmoA gene),and CO-oxidizing bacteria(coxL gene).We found significant ecosystem-specific patterns:the cbbL gene was more abundant in upland soils(averaging 9.46×10^(9)copies g^(–1))than in paddy soils(6.44×10^(9) copies g^(–1)).In contrast,methanotrophs abundance was 1 to 3 orders of magnitude higher in paddy(averaging 1.17×10^(8) copies g^(–1))than in upland(5.78×10^(6)copies g^(–1))soils.The coxL gene maintained similar abundance levels across both soil types(averaging 6.12×10^(8) vs.5.91×10^(8) copies g^(–1)).Structural equation models revealed that spatial factors primarily shaped cbbL and pmoA in uplands,whereas total bacterial abundance was the dominant predictor for all three genes in paddy soils.These results highlight distinct ecological controls on microbial functional groups and provide a predictive framework for how land use and climate change may regulate microbial mediation of carbon gas fluxes across a continental-scale transect in eastern China.展开更多
The effect of antibacterial adhesive on the biological corrosion resistance of mortar in seawater environment was studied by means of scanning electron microscope,thermogravimetric analysis,X-ray diffraction,Fourier t...The effect of antibacterial adhesive on the biological corrosion resistance of mortar in seawater environment was studied by means of scanning electron microscope,thermogravimetric analysis,X-ray diffraction,Fourier transform infrared spectroscopy,and ultra-depth microscope.The results show that the antibacterial adhesive can effectively inhibit the growth of sulfur-oxidizing bacteria in seawater,hinder their metabolism to produce biological sulfate,and reduce the formation of destructive product gypsum.The mineral composition and thermal analysis showed that the peak value of plaster diffraction peak and the mass loss of plaster dehydration in antibacterial adhesive group were significantly lower than those in blank group(without protective coating group).In addition,the electric flux of chloride ions(>400 C)in the blank group of mortar samples was higher than that in the antibacterial adhesive group(<200 C),indicating that the antibacterial adhesive can effectively reduce the permeability of chloride ions in mortar,and thus hinder the Cl-erosion in seawater.展开更多
Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient ...Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient balance within ecosystems,and enhancing ecosystem adaptability and resilience.This cycle is influenced by factors such as the restoration approach and microbial community dynamics.However,the extent to which the restoration approach alters the P cycle in karst ecosystems and the underlying microbial mechanisms remain poorly understood.The P-cycle multifunctionality index (P-cycle MFI) serves as a comprehensive indicator for evaluating soil P cycle function,and it provides insights into changes in the P cycle between different restoration approaches.To investigate the shifts in soil P-cycle MFI and microbial mechanisms between different restoration approaches,we analyzed soil available P (AP),total P (TP),microbial biomass P (MBP),and the activities of acid phosphatase (ACP) and alkaline phosphatase (ALP).These data were used to calculate the P-cycle MFI by averaging the Z-scores between two restoration approaches(artificial restoration of forest (AF) and natural restoration of forest (NF)) and a control (cropland,CP) at six subtropical karst ecosystem sites in China.We also determined the soil organic carbon (SOC),exchangeable calcium (Ca) and magnesium (Mg),pH,bulk density (BD),microbial biomass C (MBC),and microbial biomass nitrogen (MBN),as well as the community structure,relative abundance,diversity indices,and co-occurrence networks of phoD-harboring bacteria.The results showed that the community structure of phoD-harboring bacteria varied significantly among AF,NF,and CP and across different temperature gradients.These bacteria exhibited increasing complexity and tightness in co-occurrence networks from CP to AF and then to NF,along with the ACP and ALP activities,but not the TP and AP contents.The P-cycle MFI values were significantly higher in NF compared to AF and CP,and the variation was significantly explained by restoration approach,temperature,MBC,MBN,SOC,exchangeable Ca,BD,community structure of phoD-harboring bacteria,and exchangeable Mg.Furthermore,natural restoration had a more substantial impact on the P-cycle MFI than temperature by enhancing SOC,microbial biomass,the complexity and co-occurrence network tightness of the phoD-harboring bacterial community structure,and ACP and ALP activities,but it reduced soil BD.The rare genera of phoD-harboring bacteria significantly influenced the variation of soil P-cycle MFI compared to the dominant genera.This study highlights the importance of rare genera of phoD-harboring bacteria in driving soil P-cycle multifunctionality in karst ecosystems,with natural restoration being more effective than artificial methods for enhancing soil organic matter and microbial community complexity.展开更多
Anammox bacteria in constructed wetlands(CWs)play pivotal role in sustainable nitrogen transformation,yet existing studies lack comprehensive analysis of environmental gradients and microbial interactions,both key fac...Anammox bacteria in constructed wetlands(CWs)play pivotal role in sustainable nitrogen transformation,yet existing studies lack comprehensive analysis of environmental gradients and microbial interactions,both key factors in anammox bacteria enrichment.This study investigated the mechanisms driving anammox bacteria enrichment in lab-scale simulated CWs treating high-nitrogen wastewater,focusing on bacterial community re-sponses across wetland layers with various strategies,including continuous up-flow influent,nitrogen loading increase,effluent recirculation,intermittent influent,and anammox bacteria inoculation.Results showed that total relative and absolute abundances of anammox bacteria ranged from 0.77%to 12.50%and from 0.13 to 6.46×10^(7) copies/g,respectively.Dissolved oxygen and pH had significant positive correlations with the absolute abundance of anammox bacteria,while organic matter and nitrate negatively impacted their relative abundance.Permutational multivariate analysis of variance indicated that spatial heterogeneity explained more variation in anammox bacteria abundance(43.44%)compared to operational strategies(8.58%).In terms of microbial interactions,60 dominant species exhibited potential correlations with anammox bacteria,comprising 170 interactions(105 positive and 65 negative),which suggested that anammox bacteria generally foster cooperative relationships with dominant bacteria.Notably,significant interspecies interactions were observed between Candidatus Kuenenia(dominant anammox bacteria in CWs)and species within the genera Chitinivibrio-nia and Anaerolineaceae,suggesting that microbial interactions primarily manifest as indirect facilitative effects rather than direct mutualistic relationships.Given that the Normalized Stochasticity Ratio in CWs were<50%,this study inferred that environmental gradients have greater influence on anammox bacteria than microbial interactions.展开更多
Oxidative potential(OP)can be used as an indicator of the health risks of particulate matter in the air.To study the variation and sources of OP,we conducted an observation of PM_(2.5) in a megacity in southern China ...Oxidative potential(OP)can be used as an indicator of the health risks of particulate matter in the air.To study the variation and sources of OP,we conducted an observation of PM_(2.5) in a megacity in southern China in winter and spring of 2021.The results show that the average concentration of PM_(2.5) decreased by 47%from winter to spring,while volume-normalized and mass-normalized OP(i.e.,OP_(v) and OP_(m))increased by 6%and 69%,respectively.It suggests that the decline of PM_(2.5) may not necessarily decrease the health risks and the intrinsic toxicity of PM_(2.5).Variations of OP_(v) and OP_(m) among different periods were related to the different source contributions and environmental conditions.The positive matrix factorization model was used to identify the major sources of OP_(v).OP_(v) was mainly contributed by biomass burning/industrial emissions(29%),soil/road dust(20%),secondary sulfate(14%),and coal combustion(13%)in winter.Different major sources were resolved to be secondary sulfate(36%),biological sources(21%),and marine vessels(20%)in spring,presenting the substantial contribution of biological sources.The analysis shows strong associations between OP_(v) and both live and dead bacteria,further confirming the important contribution of bioaerosols to the enhancement of OP.This study highlights the importance of understanding OP in ambient PM_(2.5) in terms of public health impact and provides a new insight into the biological contribution to OP.展开更多
The mechanisms leading to neurological and neurodegenerative diseases are not completely known,and new,more effective,therapeutic treatments are necessary for most neurological pathologies.The treatment of neurologica...The mechanisms leading to neurological and neurodegenerative diseases are not completely known,and new,more effective,therapeutic treatments are necessary for most neurological pathologies.The treatment of neurological and neurodegenerative diseases is complicated due to the blood-brain barrier,which makes it difficult for drugs to access the brain areas in which they must act to improve the pathology.A tool that can help to overcome this difficulty is the use of extracellular vesicles,which can easily cross the blood-brain barrier.The extracellular vesicles are considered a main way of communication between the brain and the rest of the body,with important implications for the physiopathology and therapy of neurological diseases.In recent years,the involvement of microbiota in many neurological pathologies,as well as its possible therapeutic role,has also become evident.A key mediator in the pathologic and beneficial effects of microbiota seems to be the bacterial extracellular vesicles.There is an important communication between the brain and the intestinal microbiota(the gut-brain axis),by which the microbiota influences brain function,impacts on mental health,and plays a role in different neurological and neurodegenerative diseases.The identification of the mechanisms involved in this gut-brain axis is essential to understanding the mechanisms of neurological pathologies and to developing more effective treatments for these diseases.Bacterial extracellular vesicles would play a relevant role in these processes.This review compiles the recent information and evidence on the role of bacterial extracellular vesicles in brain pathologies and on the therapeutic utility of bacterial extracellular vesicles in neurological and neurodegenerative diseases.One advantage of bacterial extracellular vesicles compared to extracellular vesicles derived from other cell types,such as stem cells,is that bacterial extracellular vesicles are generally easier to produce and modify.Bacterial extracellular vesicles may be easily modified to target a specific pathology and/or to enhance its therapeutic efficacy.Although the studies are still scarce,they open a wide field of possibilities for future studies,which will lead to a deeper understanding of the role of microbiota and bacterial extracellular vesicles in neurological pathologies and the underlying mechanisms,as well as to the development of new treatments based on the use of bacterial extracellular vesicles in neurological diseases.展开更多
[Objectives]To assess the effects of endophytic bacteria on the growth,antioxidant responses,and the production of key secondary metabolites in Emilia prenanthoidea DC.[Methods]Three endophytic strains(H1,H2,L1)were i...[Objectives]To assess the effects of endophytic bacteria on the growth,antioxidant responses,and the production of key secondary metabolites in Emilia prenanthoidea DC.[Methods]Three endophytic strains(H1,H2,L1)were inoculated onto tissue-cultured seedlings and cultivated for 20 d under greenhouse conditions.Growth traits,reactive oxygen species(ROS)indicators,antioxidant enzyme activities,and the content of chlorogenic acid and quercetin were analyzed using one-way ANOVA followed by Tukey s test.[Results]Bacterial inoculation significantly enhanced plant performance.Treatment H2 increased plant height by 27%,chlorophyll content by 73%,and fresh weight by 31%.Levels of ROS(O^(-)_(2),H_(2)O_(2))and MDA decreased markedly,whereas the activities of POD and CAT increased.Additionally,the content of chlorogenic acid and quercetin increased by up to 67%and 64%,respectively,with both H2 and L1 treatments showing the most pronounced effects.[Conclusions]Endophytic bacteria markedly improve growth,redox balance,and phenolic accumulation in E.prenanthoidea.Strain H2 represents a promising bioinoculant for improving the medicinal quality of this species.展开更多
BACKGROUND: Sepsis is a life-threatening inflammatory condition in which the invading pathogen avoids the host's defense mechanisms and continuously stimulates and damages host cells. Consequently, many immune res...BACKGROUND: Sepsis is a life-threatening inflammatory condition in which the invading pathogen avoids the host's defense mechanisms and continuously stimulates and damages host cells. Consequently, many immune responses initially triggered for protection become harmful because of the failure to restore homeostasis, resulting in ongoing hyperinflammation and immunosuppression. METHODS: A literature review was conducted to address bacterial sepsis, describe advances in understanding complex immunological reactions, critically assess diagnostic approaches, and emphasize the importance of studying bacterial bottlenecks in the detection and treatment of sepsis.RESULTS: Diagnosing sepsis via a single laboratory test is not feasible;therefore, multiple key biomarkers are typically monitored, with a focus on trends rather than absolute values. The immediate interpretation of sepsis-associated clinical signs and symptoms, along with the use of specific and sensitive laboratory tests, is crucial for the survival of patients in the early stages. However, long-term mortality associated with sepsis is now recognized, and alongside the progression of this condition, there is an in vivo selection of adapted pathogens.CONCLUSION: Bacterial sepsis remains a significant cause of mortality across all ages and societies. While substantial progress has been made in understanding the immunological mechanisms underlying the inflammatory response, there is growing recognition that the ongoing host-pathogen interactions, including the emergence of adapted virulent strains, shape both the acute and long-term outcomes in sepsis. This underscores the urgent need for novel high-throughput diagnostic methods and a shift toward more pre-emptive, rather than reactive, treatment strategies in sepsis care.展开更多
Oryza longistaminata is an African wild rice species with valuable agronomic traits and the donor parent of perennial rice.Endophytic bacteria play an important role in host health,adaptive evolution and stress tolera...Oryza longistaminata is an African wild rice species with valuable agronomic traits and the donor parent of perennial rice.Endophytic bacteria play an important role in host health,adaptive evolution and stress tolerance.However,endophytic bacterial communities in O.longistaminata and their plant growth-promoting(PGP)effects on the perennial rice of O.longistaminata offspring are poorly understood.In this study,the endophytic bacterial diversity,composition and network structures in the root,stem,and leaf tissues of O.longistaminata were characterized using Illumina sequencing of the 16S rRNA gene.The results suggested that O.longistaminata contains a multitude of niches for different endophytic bacteria,among which the root endosphere is more complex and functionally diverse than the stem and leaf endospheres.Tissue-specific biomarkers were identified,including Paludibaculum,Pseudactinotalea and Roseimarinus and others,for roots,Blautia for stems and Lachnospiraceae NK4A136 for leaves.The endophytic bacterial network of O.longistaminata was reassembled for various functions,including degradation/utilization/assimilation,detoxification,generation of precursor metabolites and energy,glycan pathways,macromolecule modification and metabolism.A total of 163 endophytic bacterial strains with PGP traits of potassium release,phosphate solubilization,nitrogen fixation,siderophore activity,indole-3-acetic acid(IAA)production,and 1-aminocyclopropane-1-carboxylate(ACC)deaminase activity were isolated from O.longistaminata.Eleven strains identified as Enterobacter cloacae,Enterobacter ludwigii,Stenotrophomonas maltophilia,Serratia fonticola,and Bacillus velezensis showed stable colonization abilities and PGP effects on perennial rice seedlings.Inoculated plants generally exhibited an enhanced root system and greater photosynthesis,biomass accumulation and nutrient uptake.Interestingly,two strains of E.cloacae have host genotype-dependent effects on perennial rice growth.The results of this study provide insights into the endophytic bacterial ecosystems of O.longistaminata,which can potentially be used as biofertilizers for sustainable perennial rice productivity.展开更多
In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions.Then,th...In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions.Then,the impacts of the biochar(BC),M14+R27(MR),and BC+MR treatments on wheat Cd uptake and the mechanisms involved were investigated at the jointing,heading,and mature stages of wheat plants under field-plot conditions.A hydroponic experiment showed that the MR treatment significantly decreased the above-ground tissue Cd content compared with theM14 or R27 treatment.The BC+MRtreatment reduced the grain Cd content by 51.5%-67.7%and Cd translocation factor at the mature stage of wheat plants and increased the organic matter-bound Cd content by 31%-75%in the rhizosphere soils compared with the BC or MR treatment.Compared with the BC or MR treatment,the relative abundances of the biomarkers associated with Gemmatimonas,Altererythrobacter,Gammaproteobacteria,Xanthomonadaceae,Phenylobacterium,and Nocardioides in the BC+MR-treated rhizosphere microbiome decreased and negatively correlated with the organic matter-bound Cd contents.In the BC+MR-treated root interior microbiome,the relative abundance of the biomarker belonging to Exiguobacterium increased and negatively correlated with the Cd translocation factor,while the relative abundance of the biomarker belonging to Pseudonocardiaceae decreased and positively correlated with the Cd translocation factor.Our findings suggested that the BC+MR treatment reduced Cd availability and Cd transfer through affecting the abundances of these specific biomarkers in the rhizosphere soil and root interior microbiomes,leading to decreased wheat grain Cd uptake in the contaminated soil.展开更多
Rice-fish coculture(RFC)has aroused extensive concern for its contribution to food security and resource conservation,but whether it can improve soil phosphorus(P)availability and affect microbe-mediated P turnover re...Rice-fish coculture(RFC)has aroused extensive concern for its contribution to food security and resource conservation,but whether it can improve soil phosphorus(P)availability and affect microbe-mediated P turnover remains elusive.Herein,we conducted a microcosm experiment to assess the impacts of RFC combined with(50 mg P kg^(-1)as KH2PO4)and without inorganic P addition on P fractions,P availability,and phoD-harboring bacterial community composition.The results revealed that RFC without P addition significantly improved P availability and phosphatase activity in paddy soil,while soil available P(AP),pH,and microbial biomass P(MBP)contributed to regulating P fractions.Moreover,the phoD-harboring bacterial abundance was linked to phosphatase activity,AP,total carbon(TC),and total P(TP)contents,and the ratios of TC to total nitrogen(TN)and TN to TP.We also found that the keystone taxa of phoD-harboring bacteria contributed to phosphatase production as well as organic P mineralization,thereby improving P availability.Our findings suggest that RFC without P addition is beneficial for promoting the expression of phoD-harboring bacterial functions to improve the capacity of P mineralization.Overall,our study provides insights into the responses of phoD-harboring bacterial functions for P turnover to RFC combined with and without P addition,showing the potential utilization of P resources in agricultural soil and the contribution of phosphatase activity to P acquisition in agriculture ecosystem.展开更多
Diel investigations of water environments are one means to holistically understand the dynamics and functional roles of phytoplankton,bacteria and viruses in these ecosystems.They have the potential to substantially i...Diel investigations of water environments are one means to holistically understand the dynamics and functional roles of phytoplankton,bacteria and viruses in these ecosystems.They have the potential to substantially impact carbon(C),nitrogen(N)and phosphorus(P)biogeochemistry through their respective roles.This study characterizes the phytoplankton,bacteria and virus communities and the elemental composition of various C,N and P nutrients flow over three diel cycles in tropical urban lake.Our results show that ratios of C:N:P fluctuated strongly from the lack of dissolved organic phosphorus(DOP)and PO_(4).Specifically,green algae peaked during day time and exudate dissolved organic matter(DOM)that strongly modulate dissolved organic carbon(DOC):DOP ratio to diel DOP limitation.Multiple linear regression and Stella modelling emphasize the roles of viruses together with Synechococcus as important nutrient recyclers of NH_(4)and PO_(4)in nutrients-limited waters.Respective normalised surface PO_(4)and combined surface and bottom NH_(4)concentration selected both viruses and Synechococcus as important drivers.Process model of N and P biogeochemical cycles can achieve 69%and 57%similar to observed concentration of NH_(4)and PO_(4),respectively.A short latent period of 9 hr was calculated,in addition to the calibrated high infectivity of viruses to Synechococcus.Taken together,the rapid turn-over between Synechococcus and viruses has biogeochemical significance,where the rapid recycling of essential nutrients allows for shortcuts in the N and P cycle,supporting a wide range of microbes.展开更多
Because of the recent widespread usage of antibiotics,the acquisition and dissemination of antibiotic-resistance genes(ARGs)were prevalent in the majority of habitats.Generally,the biological wastewater treatment proc...Because of the recent widespread usage of antibiotics,the acquisition and dissemination of antibiotic-resistance genes(ARGs)were prevalent in the majority of habitats.Generally,the biological wastewater treatment processes used in wastewater treatment plants have a limited efficiencies of antibiotics resistant bacteria(ARB)disinfection and ARGs degradation and even promote the proliferation of ARGs.Problematically,ARB and ARGs in effluent pose potential risks if they are not further treated.Photocatalytic oxidation is considered a promising disinfection technology,where the photocatalytic process generates many free radicals that enhance the interaction between light and deoxyribonucleic acid(DNA)for ARB elimination and subsequent degradation of ARGs.This reviewaims to illustrate the progress of photocatalytic oxidation technology for removing antibiotics resistant(AR)from wastewater in recent years.We discuss the sources and transfer of ARGs in wastewater.The overall removal efficiencies of ultraviolet radiation(UV)/chlorination,UV/ozone,UV/H_(2)O_(2),and UV/sulfate-radical based system for ARB and ARGs,as well as the experimental parameters and removal mechanisms,are systematically discussed.The contribution of photocatalytic materials based on TiO_(2) and g-C_(3)N_(4) to the inactivation of ARB and degradation of ARGs is highlighted,producingmany free radicals to attack ARB and ARGs while effectively limiting the horizontal gene transfer(HGT)in wastewater.Finally,based on the reviewed studies,future research directions are proposed to realize specific photocatalytic oxidation technology applications and overcome current challenges.展开更多
Soil microbial communities are key factors in maintaining ecosystem multifunctionality(EMF).However,the distribution patterns of bacterial diversity and how the different bacterial taxa and their diversity dimensions ...Soil microbial communities are key factors in maintaining ecosystem multifunctionality(EMF).However,the distribution patterns of bacterial diversity and how the different bacterial taxa and their diversity dimensions affect EMF remain largely unknown.Here,we investigated variation in three measures of diversity(alpha diversity,community composition and network complexity)among rare,intermediate,and abundant taxa across a latitudinal gradient spanning five forest plots in Yunnan Province,China and examined their contributions on EMF.We aimed to characterize the diversity distributions of bacterial groups across latitudes and to assess the differences in the mechanisms underlying their contributions to EMF.We found that multifaceted diversity(i.e.,diversity assessed by the three different metrics)of rare,intermediate,and abundant bacteria generally decreased with increasing latitude.More importantly,we found that rare bacterial taxa tended to be more diverse,but they contributed less to EMF than intermediate or abundant bacteria.Among the three dimensions of diversity we assessed,only community composition significantly affected EMF across all locations,while alpha diversity had a negative effect,and network complexity showed no significant impact.Our study further emphasizes the importance of intermediate and abundant bacterial taxa as well as community composition to EMF and provides a theoretical basis for investigating the mechanisms by which belowground microorganisms drive EMF along a latitudinal gradient.展开更多
Bacterial infection is a major threat to global public health,and can cause serious diseases such as bacterial skin infection and foodborne diseases.It is essential to develop a new method to rapidly diagnose clinical...Bacterial infection is a major threat to global public health,and can cause serious diseases such as bacterial skin infection and foodborne diseases.It is essential to develop a new method to rapidly diagnose clinical multiple bacterial infections and monitor food microbial contamination in production sites in real-time.In this work,we developed a 4-mercaptophenylboronic acid gold nanoparticles(4-MPBA-AuNPs)-functionalized hydrogel microneedle(MPBA-H-MN)for bacteria detection in skin interstitial fluid.MPBA-H-MN could conveniently capture and enrich a variety of bacteria within 5 min.Surface enhanced Raman spectroscopy(SERS)detection was then performed and combined with machine learning technology to distinguish and identify a variety of bacteria.Overall,the capture efficiency of this method exceeded 50%.In the concentration range of 1×10_(7) to 1×10^(10) colony-forming units/mL(CFU/mL),the corresponding SERS intensity showed a certain linear relationship with the bacterial concentration.Using random forest(RF)-based machine learning,bacteria were effectively distinguished with an accuracy of 97.87%.In addition,the harmless disposal of used MNs by photothermal ablation was convenient,environmentally friendly,and inexpensive.This technique provided a potential method for rapid and real-time diagnosis of multiple clinical bacterial infections and for monitoring microbial contamination of food in production sites.展开更多
Lead(Pb)and zinc(Zn)are widely recognized as common environmental contaminants,contributing to soil degradation and posing risks to environmental health.Combining functional carbon-based materials with microorganisms ...Lead(Pb)and zinc(Zn)are widely recognized as common environmental contaminants,contributing to soil degradation and posing risks to environmental health.Combining functional carbon-based materials with microorganisms has been considered as an effective and environmentally friendly strategy for remediating Pb/Zn-contaminated soil.However,there is still a lack of understanding the connection between heavy metal immobilization and plant responses,which hampers practical applications.Here,a 90-day pot experiment was conducted to investigate the integrated effects of biochar(WS700)and microorganisms including inorganic phosphate-solubilizing bacteria(IPSB)and sulfate reducing bacteria(SRB)on Pb and Zn synchronous immobilization and the physiological responses of Brassica rapa var.chinensis(Brassica).Compared with CK,bacteria-loaded biochar treatment declined the exchangeable Pb and Zn fraction by 94.69%−98.37%and 94.55%−99.52%,while increasing the residual state Pb and Zn by 75.50%−208.58%and 96.71%−110.85%,respectively.Three amendments enhanced Brassica growth by improving total chlorophyll content and superoxide dismutase(SOD)and peroxidase(POD)activities.The bacteria-loaded biochar treatment effectively regulated stomatal conductance and reduced intercellular CO_(2) concentration.Moreover,compared with CK,three amendments reduced MDA content by 28.84%,28.30%and 41.60%,respectively,under the high concentration of Pb and Zn.The findings demonstrated the significant role of bacterial-biochar consortia in immobilizing Pb and Zn and mitigating Pb and Zn-induced stress in plants by regulating photosynthetic characteristics and antioxidant enzyme activities.展开更多
Plate culture counting and strain isolation methods were utilized to assess the species richness and abundance of planktonic and attached bacteria on glass plates in the surface and bottom seawater of Qingdao Middle H...Plate culture counting and strain isolation methods were utilized to assess the species richness and abundance of planktonic and attached bacteria on glass plates in the surface and bottom seawater of Qingdao Middle Harbor over a year,with monthly and quarterly sampling.Both species richness and bacterial numbers exhibited seasonal variations.Specifically,the abundance of attached bacteria and bacterioplankton peaked in June and July,corresponding to higher water temperatures in summer and autumn,while lower abundances were noted in January and December during cooler periods.Throughout the year,the species richness of attached bacteria consistently exceeded that of planktonic bacteria in both shallow and deep waters.Pseudoalteromonas emerged as the most prevalent genus among both planktonic and attached bacteria in surface and bottom seawater samples.Furthermore,the magnitude of changes in species richness and abundance for attached bacteria(0.66×10^(5)-15.85×10^(5)CFU/cm^(2))was greater than that observed for planktonic bacteria(0.58×10^(8)-5.33×10^(8)CFU/L).We propose that the attached bacterial populations,situated in limited microenvironments within the larger seawater ecosystem,exhibit heightened sensitivity to environmental fluctuations,resulting in more rapid shifts in population dynamics and lower ecological stability.The theoretical implications and potential applications of these findings warrant further investigation.展开更多
Salt-tolerant bacteria associated with halophytes enhance plant resistance and adaptation to environmental stress.The purpose of this study was to investigate the diversity and plant-beneficial traits of bacteria asso...Salt-tolerant bacteria associated with halophytes enhance plant resistance and adaptation to environmental stress.The purpose of this study was to investigate the diversity and plant-beneficial traits of bacteria associated with three halophytes in an arid land,Northwest China.The bacterial strains were isolated from the roots,shoots,rhizosphere,and bulk soil of three halophytes,i.e.,Salicornia europaea L.,Kalidium foliatum(Pall.)Moq.,and Suaeda aralocaspica(Bunge)Freitag&Schütze,collected from the saline soils near to the Wujiaqu City,Xinjiang,Northwest China.A total of 567 strains were isolated and identified from these three halophytes belonging to 4 phyla,6 classes,25 orders,36 families,and 66 genera,including 147 potential novel species.A total of 213 strains exhibited one or more plant growthpromoting properties,while 20 strains demonstrated multiple in vitro plant growth-promoting activities,including phosphate solubilization,nitrogen fixation,siderophore production,and production of hydrolytic enzymes such as protease and cellulase.Our findings showed that halophytes in the arid land harbor diverse bacteria with the potential to enhance plant growth and adaptability under challenging environmental conditions.展开更多
Objective: This study assessed the effects of consuming acetic acid bacteria (Gluconacetobacter hansenii GK-1) for 12 weeks on fatigue induced by temporary mental stress. Methods: This randomized, double-blind, placeb...Objective: This study assessed the effects of consuming acetic acid bacteria (Gluconacetobacter hansenii GK-1) for 12 weeks on fatigue induced by temporary mental stress. Methods: This randomized, double-blind, placebo-controlled, parallel-group study included 100 healthy male and female adults aged 20 - 64 years. Participants consumed either the G. hansenii GK-1 supplement (9 × 10⁹ cells/day) or a placebo daily for 12 weeks. The impact of temporary mental stress on fatigue in G. hansenii GK-1 was assessed using a Visual Analog Scale (VAS) before the study began and after 12 weeks of supplementation. Results: Subjective fatigue measured by Visual Analog Scale (VAS) showed a significant decrease in fatigue induced by temporary mental stress after 12 weeks of consumption in the G. hansenii GK-1 group compared with the placebo group. No adverse events were attributed to G. hansenii GK-1. These findings confirm that continuous oral ingestion of G. hansenii GK-1 by healthy Japanese adults reduces feelings of fatigue caused by temporary mental stress.展开更多
Both the broad-spectrum bactericidal properties of disinfectants and the inhibitory effects of antibiotics pose potential threats to the activity,functionality,and probiotic properties of Lactid acid bacteria(LAB).The...Both the broad-spectrum bactericidal properties of disinfectants and the inhibitory effects of antibiotics pose potential threats to the activity,functionality,and probiotic properties of Lactid acid bacteria(LAB).Therefore,it is essential to systematically evaluate the tolerance of lactic acid bacteria to common disinfectants and antibiotics.This study assessed 60 LAB strains isolated from the fermented foods for their tolerance to seven disinfectants and nine antibiotics.The results indicated that,compared to pathogenic bacteria,most LAB exhibited stronger tolerance to disinfectants.Sub-inhibitory concentrations of disinfectants inhibited biofilm formation in most LAB,while sub-inhibitory concentrations of glutaraldehyde tended to promote biofilm formation.This suggests that commonly used disinfectants can eliminate pathogenic bacteria without killing LAB,providing guidance for disinfectant use.LAB were highly sensitive to ampicillin and chloramphenicol,while showing some tolerance to norfloxacin,polymyxin,and sulfamethoxazole.This indicates LAB have a notable antibiotic resistance profile,which includes both natural resistance characteristics and instances of acquired resistance,along with multiple drug resistance and cross-resistance between antibiotics and disinfectants.This study provides an important guidance for disinfection practices in industrial utilizing LAB,such as food and biomedicine,and offers a reference for the use of antibiotics.展开更多
基金financially supported by the National Key R&D Program of China(2023YFD1902802)the Science Fund for Distinguished Young Scholars in Hunan,China(2024JJ2052)+3 种基金the Natural Science Foundation of Fujian Province,China(2022J05263)the Nanping City Science and Technology Plan Project,China(NP2021KTS02)the Talent Introduction Project of Wuyi University,China(YJ202117)the Open Foundation of State Key Laboratory of Microbial Technology in Shandong University,China(M2022-05)。
文摘Microorganisms carrying cbbL,pmoA and coxL genes play crucial roles in regulating soil-atmosphere exchanges of carbon trace gases(CO_(2),CH_(4),and CO).However,the geographical distribution patterns of these functional genes in agricultural ecosystems and their environmental drivers remain poorly understood.Here,we surveyed agricultural soils across four climate zones(tropical,subtropical,warm temperate,and mid-temperate)in eastern China to quantify the abundances of CO_(2)-assimilating bacteria(cbbL gene),methanotrophs(pmoA gene),and CO-oxidizing bacteria(coxL gene).We found significant ecosystem-specific patterns:the cbbL gene was more abundant in upland soils(averaging 9.46×10^(9)copies g^(–1))than in paddy soils(6.44×10^(9) copies g^(–1)).In contrast,methanotrophs abundance was 1 to 3 orders of magnitude higher in paddy(averaging 1.17×10^(8) copies g^(–1))than in upland(5.78×10^(6)copies g^(–1))soils.The coxL gene maintained similar abundance levels across both soil types(averaging 6.12×10^(8) vs.5.91×10^(8) copies g^(–1)).Structural equation models revealed that spatial factors primarily shaped cbbL and pmoA in uplands,whereas total bacterial abundance was the dominant predictor for all three genes in paddy soils.These results highlight distinct ecological controls on microbial functional groups and provide a predictive framework for how land use and climate change may regulate microbial mediation of carbon gas fluxes across a continental-scale transect in eastern China.
基金Funded by the National Natural Science Foundation of China(Nos.52278269,52278268,52178264)Tianjin Outstanding Young Scholars Science Fund Project(No.22JCJQJC00020)Key Project of Tianjin Natural Science Foundation(No.23JCZDJC00430)。
文摘The effect of antibacterial adhesive on the biological corrosion resistance of mortar in seawater environment was studied by means of scanning electron microscope,thermogravimetric analysis,X-ray diffraction,Fourier transform infrared spectroscopy,and ultra-depth microscope.The results show that the antibacterial adhesive can effectively inhibit the growth of sulfur-oxidizing bacteria in seawater,hinder their metabolism to produce biological sulfate,and reduce the formation of destructive product gypsum.The mineral composition and thermal analysis showed that the peak value of plaster diffraction peak and the mass loss of plaster dehydration in antibacterial adhesive group were significantly lower than those in blank group(without protective coating group).In addition,the electric flux of chloride ions(>400 C)in the blank group of mortar samples was higher than that in the antibacterial adhesive group(<200 C),indicating that the antibacterial adhesive can effectively reduce the permeability of chloride ions in mortar,and thus hinder the Cl-erosion in seawater.
基金supported by the National Key Research and Development Program of China (2022YFF1300705)the Key Research and Development Project of Guangxi,China (Guike AB24010051)+1 种基金the National Natural Science Foundation of China (42261011,32271730 and U20A2011)the Central Public Welfare Research Institutes,Chinese Academy of Geological Sciences (2023020)。
文摘Phosphorus (P) is an essential nutrient element that is critical for plant growth and ecosystem functionality.The soil P cycle plays multiple roles,such as sustaining plant growth and productivity,regulating nutrient balance within ecosystems,and enhancing ecosystem adaptability and resilience.This cycle is influenced by factors such as the restoration approach and microbial community dynamics.However,the extent to which the restoration approach alters the P cycle in karst ecosystems and the underlying microbial mechanisms remain poorly understood.The P-cycle multifunctionality index (P-cycle MFI) serves as a comprehensive indicator for evaluating soil P cycle function,and it provides insights into changes in the P cycle between different restoration approaches.To investigate the shifts in soil P-cycle MFI and microbial mechanisms between different restoration approaches,we analyzed soil available P (AP),total P (TP),microbial biomass P (MBP),and the activities of acid phosphatase (ACP) and alkaline phosphatase (ALP).These data were used to calculate the P-cycle MFI by averaging the Z-scores between two restoration approaches(artificial restoration of forest (AF) and natural restoration of forest (NF)) and a control (cropland,CP) at six subtropical karst ecosystem sites in China.We also determined the soil organic carbon (SOC),exchangeable calcium (Ca) and magnesium (Mg),pH,bulk density (BD),microbial biomass C (MBC),and microbial biomass nitrogen (MBN),as well as the community structure,relative abundance,diversity indices,and co-occurrence networks of phoD-harboring bacteria.The results showed that the community structure of phoD-harboring bacteria varied significantly among AF,NF,and CP and across different temperature gradients.These bacteria exhibited increasing complexity and tightness in co-occurrence networks from CP to AF and then to NF,along with the ACP and ALP activities,but not the TP and AP contents.The P-cycle MFI values were significantly higher in NF compared to AF and CP,and the variation was significantly explained by restoration approach,temperature,MBC,MBN,SOC,exchangeable Ca,BD,community structure of phoD-harboring bacteria,and exchangeable Mg.Furthermore,natural restoration had a more substantial impact on the P-cycle MFI than temperature by enhancing SOC,microbial biomass,the complexity and co-occurrence network tightness of the phoD-harboring bacterial community structure,and ACP and ALP activities,but it reduced soil BD.The rare genera of phoD-harboring bacteria significantly influenced the variation of soil P-cycle MFI compared to the dominant genera.This study highlights the importance of rare genera of phoD-harboring bacteria in driving soil P-cycle multifunctionality in karst ecosystems,with natural restoration being more effective than artificial methods for enhancing soil organic matter and microbial community complexity.
基金supported by Natural Science Foundation of Xiamen,China(No.3502Z20227232)the STS Project of Fujian-CAS(No.2023T3018)Bureau of International Cooperation,Chinese Academy of Sciences(No.322GJHZ2022035MI).
文摘Anammox bacteria in constructed wetlands(CWs)play pivotal role in sustainable nitrogen transformation,yet existing studies lack comprehensive analysis of environmental gradients and microbial interactions,both key factors in anammox bacteria enrichment.This study investigated the mechanisms driving anammox bacteria enrichment in lab-scale simulated CWs treating high-nitrogen wastewater,focusing on bacterial community re-sponses across wetland layers with various strategies,including continuous up-flow influent,nitrogen loading increase,effluent recirculation,intermittent influent,and anammox bacteria inoculation.Results showed that total relative and absolute abundances of anammox bacteria ranged from 0.77%to 12.50%and from 0.13 to 6.46×10^(7) copies/g,respectively.Dissolved oxygen and pH had significant positive correlations with the absolute abundance of anammox bacteria,while organic matter and nitrate negatively impacted their relative abundance.Permutational multivariate analysis of variance indicated that spatial heterogeneity explained more variation in anammox bacteria abundance(43.44%)compared to operational strategies(8.58%).In terms of microbial interactions,60 dominant species exhibited potential correlations with anammox bacteria,comprising 170 interactions(105 positive and 65 negative),which suggested that anammox bacteria generally foster cooperative relationships with dominant bacteria.Notably,significant interspecies interactions were observed between Candidatus Kuenenia(dominant anammox bacteria in CWs)and species within the genera Chitinivibrio-nia and Anaerolineaceae,suggesting that microbial interactions primarily manifest as indirect facilitative effects rather than direct mutualistic relationships.Given that the Normalized Stochasticity Ratio in CWs were<50%,this study inferred that environmental gradients have greater influence on anammox bacteria than microbial interactions.
基金supported by the National Natural Science Foundation of China(No.41975156)and the Fundamental Research Funds for the Central Universities.
文摘Oxidative potential(OP)can be used as an indicator of the health risks of particulate matter in the air.To study the variation and sources of OP,we conducted an observation of PM_(2.5) in a megacity in southern China in winter and spring of 2021.The results show that the average concentration of PM_(2.5) decreased by 47%from winter to spring,while volume-normalized and mass-normalized OP(i.e.,OP_(v) and OP_(m))increased by 6%and 69%,respectively.It suggests that the decline of PM_(2.5) may not necessarily decrease the health risks and the intrinsic toxicity of PM_(2.5).Variations of OP_(v) and OP_(m) among different periods were related to the different source contributions and environmental conditions.The positive matrix factorization model was used to identify the major sources of OP_(v).OP_(v) was mainly contributed by biomass burning/industrial emissions(29%),soil/road dust(20%),secondary sulfate(14%),and coal combustion(13%)in winter.Different major sources were resolved to be secondary sulfate(36%),biological sources(21%),and marine vessels(20%)in spring,presenting the substantial contribution of biological sources.The analysis shows strong associations between OP_(v) and both live and dead bacteria,further confirming the important contribution of bioaerosols to the enhancement of OP.This study highlights the importance of understanding OP in ambient PM_(2.5) in terms of public health impact and provides a new insight into the biological contribution to OP.
基金funded by the Ministerio de Ciencia e Innovación Spain(PID2020-113388RB-I00,AEI/10.13039/501100011033)Consellería de Innovación,Universidades,Ciencia y Sociedad Digital,Generalitat Valenciana(CIPROM/2021/082)+2 种基金co-funded with European Regional Development Funds(ERDF)(PID2020-113388RB-I00,and CIPROM/2021/082)PID2022-136874OB-C33 from MCIN/AEI/10.13039/501100011033by the European Union NextGenerationEU/PRTR(to VF).
文摘The mechanisms leading to neurological and neurodegenerative diseases are not completely known,and new,more effective,therapeutic treatments are necessary for most neurological pathologies.The treatment of neurological and neurodegenerative diseases is complicated due to the blood-brain barrier,which makes it difficult for drugs to access the brain areas in which they must act to improve the pathology.A tool that can help to overcome this difficulty is the use of extracellular vesicles,which can easily cross the blood-brain barrier.The extracellular vesicles are considered a main way of communication between the brain and the rest of the body,with important implications for the physiopathology and therapy of neurological diseases.In recent years,the involvement of microbiota in many neurological pathologies,as well as its possible therapeutic role,has also become evident.A key mediator in the pathologic and beneficial effects of microbiota seems to be the bacterial extracellular vesicles.There is an important communication between the brain and the intestinal microbiota(the gut-brain axis),by which the microbiota influences brain function,impacts on mental health,and plays a role in different neurological and neurodegenerative diseases.The identification of the mechanisms involved in this gut-brain axis is essential to understanding the mechanisms of neurological pathologies and to developing more effective treatments for these diseases.Bacterial extracellular vesicles would play a relevant role in these processes.This review compiles the recent information and evidence on the role of bacterial extracellular vesicles in brain pathologies and on the therapeutic utility of bacterial extracellular vesicles in neurological and neurodegenerative diseases.One advantage of bacterial extracellular vesicles compared to extracellular vesicles derived from other cell types,such as stem cells,is that bacterial extracellular vesicles are generally easier to produce and modify.Bacterial extracellular vesicles may be easily modified to target a specific pathology and/or to enhance its therapeutic efficacy.Although the studies are still scarce,they open a wide field of possibilities for future studies,which will lead to a deeper understanding of the role of microbiota and bacterial extracellular vesicles in neurological pathologies and the underlying mechanisms,as well as to the development of new treatments based on the use of bacterial extracellular vesicles in neurological diseases.
文摘[Objectives]To assess the effects of endophytic bacteria on the growth,antioxidant responses,and the production of key secondary metabolites in Emilia prenanthoidea DC.[Methods]Three endophytic strains(H1,H2,L1)were inoculated onto tissue-cultured seedlings and cultivated for 20 d under greenhouse conditions.Growth traits,reactive oxygen species(ROS)indicators,antioxidant enzyme activities,and the content of chlorogenic acid and quercetin were analyzed using one-way ANOVA followed by Tukey s test.[Results]Bacterial inoculation significantly enhanced plant performance.Treatment H2 increased plant height by 27%,chlorophyll content by 73%,and fresh weight by 31%.Levels of ROS(O^(-)_(2),H_(2)O_(2))and MDA decreased markedly,whereas the activities of POD and CAT increased.Additionally,the content of chlorogenic acid and quercetin increased by up to 67%and 64%,respectively,with both H2 and L1 treatments showing the most pronounced effects.[Conclusions]Endophytic bacteria markedly improve growth,redox balance,and phenolic accumulation in E.prenanthoidea.Strain H2 represents a promising bioinoculant for improving the medicinal quality of this species.
基金funded by the Deanship of Scientific Research (DSR) at King Abdulaziz UniversityJeddah+1 种基金Saudi Arabiaunder grant number G-150-248-1443。
文摘BACKGROUND: Sepsis is a life-threatening inflammatory condition in which the invading pathogen avoids the host's defense mechanisms and continuously stimulates and damages host cells. Consequently, many immune responses initially triggered for protection become harmful because of the failure to restore homeostasis, resulting in ongoing hyperinflammation and immunosuppression. METHODS: A literature review was conducted to address bacterial sepsis, describe advances in understanding complex immunological reactions, critically assess diagnostic approaches, and emphasize the importance of studying bacterial bottlenecks in the detection and treatment of sepsis.RESULTS: Diagnosing sepsis via a single laboratory test is not feasible;therefore, multiple key biomarkers are typically monitored, with a focus on trends rather than absolute values. The immediate interpretation of sepsis-associated clinical signs and symptoms, along with the use of specific and sensitive laboratory tests, is crucial for the survival of patients in the early stages. However, long-term mortality associated with sepsis is now recognized, and alongside the progression of this condition, there is an in vivo selection of adapted pathogens.CONCLUSION: Bacterial sepsis remains a significant cause of mortality across all ages and societies. While substantial progress has been made in understanding the immunological mechanisms underlying the inflammatory response, there is growing recognition that the ongoing host-pathogen interactions, including the emergence of adapted virulent strains, shape both the acute and long-term outcomes in sepsis. This underscores the urgent need for novel high-throughput diagnostic methods and a shift toward more pre-emptive, rather than reactive, treatment strategies in sepsis care.
基金supported by funding from the National Natural Science Foundation of China(32060593 and 32060474)the Yunnan Provincial Science and Technology Department+4 种基金China(202101AT070021 and 202101AS070001)the Yunnan Provincial Department of Education Science Research Fund ProjectChina(2023J0006)the Graduate Innovation Project of Yunnan UniversityChina(KC-22223012 and ZC-22222760)。
文摘Oryza longistaminata is an African wild rice species with valuable agronomic traits and the donor parent of perennial rice.Endophytic bacteria play an important role in host health,adaptive evolution and stress tolerance.However,endophytic bacterial communities in O.longistaminata and their plant growth-promoting(PGP)effects on the perennial rice of O.longistaminata offspring are poorly understood.In this study,the endophytic bacterial diversity,composition and network structures in the root,stem,and leaf tissues of O.longistaminata were characterized using Illumina sequencing of the 16S rRNA gene.The results suggested that O.longistaminata contains a multitude of niches for different endophytic bacteria,among which the root endosphere is more complex and functionally diverse than the stem and leaf endospheres.Tissue-specific biomarkers were identified,including Paludibaculum,Pseudactinotalea and Roseimarinus and others,for roots,Blautia for stems and Lachnospiraceae NK4A136 for leaves.The endophytic bacterial network of O.longistaminata was reassembled for various functions,including degradation/utilization/assimilation,detoxification,generation of precursor metabolites and energy,glycan pathways,macromolecule modification and metabolism.A total of 163 endophytic bacterial strains with PGP traits of potassium release,phosphate solubilization,nitrogen fixation,siderophore activity,indole-3-acetic acid(IAA)production,and 1-aminocyclopropane-1-carboxylate(ACC)deaminase activity were isolated from O.longistaminata.Eleven strains identified as Enterobacter cloacae,Enterobacter ludwigii,Stenotrophomonas maltophilia,Serratia fonticola,and Bacillus velezensis showed stable colonization abilities and PGP effects on perennial rice seedlings.Inoculated plants generally exhibited an enhanced root system and greater photosynthesis,biomass accumulation and nutrient uptake.Interestingly,two strains of E.cloacae have host genotype-dependent effects on perennial rice growth.The results of this study provide insights into the endophytic bacterial ecosystems of O.longistaminata,which can potentially be used as biofertilizers for sustainable perennial rice productivity.
基金supported by the National Natural Science Foundation of China(No.41977199).
文摘In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions.Then,the impacts of the biochar(BC),M14+R27(MR),and BC+MR treatments on wheat Cd uptake and the mechanisms involved were investigated at the jointing,heading,and mature stages of wheat plants under field-plot conditions.A hydroponic experiment showed that the MR treatment significantly decreased the above-ground tissue Cd content compared with theM14 or R27 treatment.The BC+MRtreatment reduced the grain Cd content by 51.5%-67.7%and Cd translocation factor at the mature stage of wheat plants and increased the organic matter-bound Cd content by 31%-75%in the rhizosphere soils compared with the BC or MR treatment.Compared with the BC or MR treatment,the relative abundances of the biomarkers associated with Gemmatimonas,Altererythrobacter,Gammaproteobacteria,Xanthomonadaceae,Phenylobacterium,and Nocardioides in the BC+MR-treated rhizosphere microbiome decreased and negatively correlated with the organic matter-bound Cd contents.In the BC+MR-treated root interior microbiome,the relative abundance of the biomarker belonging to Exiguobacterium increased and negatively correlated with the Cd translocation factor,while the relative abundance of the biomarker belonging to Pseudonocardiaceae decreased and positively correlated with the Cd translocation factor.Our findings suggested that the BC+MR treatment reduced Cd availability and Cd transfer through affecting the abundances of these specific biomarkers in the rhizosphere soil and root interior microbiomes,leading to decreased wheat grain Cd uptake in the contaminated soil.
基金supported by the Key-Area Research and Development Program of Guangdong Province,China(No.2021B0202030002)the Science and Technology Planning Project of Guangdong Province,China(No.2019B030301007)+2 种基金the Guangdong Provincial Special Project of Rural Revitalization Strategy,China(No.(2021)12)the Joint Team Project of Guangdong Laboratory for Lingnan Modern Agriculture,China(No.NT2021010)the Innovation Team Construction Project of Modern Agricultural Industry Technology Systems of Guangdong Province,China(No.2022KJ105).
文摘Rice-fish coculture(RFC)has aroused extensive concern for its contribution to food security and resource conservation,but whether it can improve soil phosphorus(P)availability and affect microbe-mediated P turnover remains elusive.Herein,we conducted a microcosm experiment to assess the impacts of RFC combined with(50 mg P kg^(-1)as KH2PO4)and without inorganic P addition on P fractions,P availability,and phoD-harboring bacterial community composition.The results revealed that RFC without P addition significantly improved P availability and phosphatase activity in paddy soil,while soil available P(AP),pH,and microbial biomass P(MBP)contributed to regulating P fractions.Moreover,the phoD-harboring bacterial abundance was linked to phosphatase activity,AP,total carbon(TC),and total P(TP)contents,and the ratios of TC to total nitrogen(TN)and TN to TP.We also found that the keystone taxa of phoD-harboring bacteria contributed to phosphatase production as well as organic P mineralization,thereby improving P availability.Our findings suggest that RFC without P addition is beneficial for promoting the expression of phoD-harboring bacterial functions to improve the capacity of P mineralization.Overall,our study provides insights into the responses of phoD-harboring bacterial functions for P turnover to RFC combined with and without P addition,showing the potential utilization of P resources in agricultural soil and the contribution of phosphatase activity to P acquisition in agriculture ecosystem.
文摘Diel investigations of water environments are one means to holistically understand the dynamics and functional roles of phytoplankton,bacteria and viruses in these ecosystems.They have the potential to substantially impact carbon(C),nitrogen(N)and phosphorus(P)biogeochemistry through their respective roles.This study characterizes the phytoplankton,bacteria and virus communities and the elemental composition of various C,N and P nutrients flow over three diel cycles in tropical urban lake.Our results show that ratios of C:N:P fluctuated strongly from the lack of dissolved organic phosphorus(DOP)and PO_(4).Specifically,green algae peaked during day time and exudate dissolved organic matter(DOM)that strongly modulate dissolved organic carbon(DOC):DOP ratio to diel DOP limitation.Multiple linear regression and Stella modelling emphasize the roles of viruses together with Synechococcus as important nutrient recyclers of NH_(4)and PO_(4)in nutrients-limited waters.Respective normalised surface PO_(4)and combined surface and bottom NH_(4)concentration selected both viruses and Synechococcus as important drivers.Process model of N and P biogeochemical cycles can achieve 69%and 57%similar to observed concentration of NH_(4)and PO_(4),respectively.A short latent period of 9 hr was calculated,in addition to the calibrated high infectivity of viruses to Synechococcus.Taken together,the rapid turn-over between Synechococcus and viruses has biogeochemical significance,where the rapid recycling of essential nutrients allows for shortcuts in the N and P cycle,supporting a wide range of microbes.
基金supported by the National Natural Science Foundation of China (Nos.52100182 and 52300204)the the Science and Technology Innovation Program of Hunan Province (No.2023RC3122).
文摘Because of the recent widespread usage of antibiotics,the acquisition and dissemination of antibiotic-resistance genes(ARGs)were prevalent in the majority of habitats.Generally,the biological wastewater treatment processes used in wastewater treatment plants have a limited efficiencies of antibiotics resistant bacteria(ARB)disinfection and ARGs degradation and even promote the proliferation of ARGs.Problematically,ARB and ARGs in effluent pose potential risks if they are not further treated.Photocatalytic oxidation is considered a promising disinfection technology,where the photocatalytic process generates many free radicals that enhance the interaction between light and deoxyribonucleic acid(DNA)for ARB elimination and subsequent degradation of ARGs.This reviewaims to illustrate the progress of photocatalytic oxidation technology for removing antibiotics resistant(AR)from wastewater in recent years.We discuss the sources and transfer of ARGs in wastewater.The overall removal efficiencies of ultraviolet radiation(UV)/chlorination,UV/ozone,UV/H_(2)O_(2),and UV/sulfate-radical based system for ARB and ARGs,as well as the experimental parameters and removal mechanisms,are systematically discussed.The contribution of photocatalytic materials based on TiO_(2) and g-C_(3)N_(4) to the inactivation of ARB and degradation of ARGs is highlighted,producingmany free radicals to attack ARB and ARGs while effectively limiting the horizontal gene transfer(HGT)in wastewater.Finally,based on the reviewed studies,future research directions are proposed to realize specific photocatalytic oxidation technology applications and overcome current challenges.
基金supported by the Fundamental Research Funds of Chinese Academy of Forestry(Nos.CAFYBB2022SY037,CAFYBB2021ZA002 and CAFYBB2022QC002)the Basic Research Foundation of Yunnan Province(Grant No.202201AT070264).
文摘Soil microbial communities are key factors in maintaining ecosystem multifunctionality(EMF).However,the distribution patterns of bacterial diversity and how the different bacterial taxa and their diversity dimensions affect EMF remain largely unknown.Here,we investigated variation in three measures of diversity(alpha diversity,community composition and network complexity)among rare,intermediate,and abundant taxa across a latitudinal gradient spanning five forest plots in Yunnan Province,China and examined their contributions on EMF.We aimed to characterize the diversity distributions of bacterial groups across latitudes and to assess the differences in the mechanisms underlying their contributions to EMF.We found that multifaceted diversity(i.e.,diversity assessed by the three different metrics)of rare,intermediate,and abundant bacteria generally decreased with increasing latitude.More importantly,we found that rare bacterial taxa tended to be more diverse,but they contributed less to EMF than intermediate or abundant bacteria.Among the three dimensions of diversity we assessed,only community composition significantly affected EMF across all locations,while alpha diversity had a negative effect,and network complexity showed no significant impact.Our study further emphasizes the importance of intermediate and abundant bacterial taxa as well as community composition to EMF and provides a theoretical basis for investigating the mechanisms by which belowground microorganisms drive EMF along a latitudinal gradient.
基金supported by the National Natural Science Foundation of China(Grant Nos.:82204340,82173954,and 82073815)the Natural Science Foundation of Jiangsu Province,China(Grant No.:BK20221048)+1 种基金the Jiangsu Funding Program for Excellent Postdoctoral Talent,China(Grant No.:2022ZB295)Key Laboratory Project of Quality Control of Chinese Herbal Medicines and Decoction Pieces,Gansu Institute for Drug Control,China(Grant No.:2024GSMPA-KL02).
文摘Bacterial infection is a major threat to global public health,and can cause serious diseases such as bacterial skin infection and foodborne diseases.It is essential to develop a new method to rapidly diagnose clinical multiple bacterial infections and monitor food microbial contamination in production sites in real-time.In this work,we developed a 4-mercaptophenylboronic acid gold nanoparticles(4-MPBA-AuNPs)-functionalized hydrogel microneedle(MPBA-H-MN)for bacteria detection in skin interstitial fluid.MPBA-H-MN could conveniently capture and enrich a variety of bacteria within 5 min.Surface enhanced Raman spectroscopy(SERS)detection was then performed and combined with machine learning technology to distinguish and identify a variety of bacteria.Overall,the capture efficiency of this method exceeded 50%.In the concentration range of 1×10_(7) to 1×10^(10) colony-forming units/mL(CFU/mL),the corresponding SERS intensity showed a certain linear relationship with the bacterial concentration.Using random forest(RF)-based machine learning,bacteria were effectively distinguished with an accuracy of 97.87%.In addition,the harmless disposal of used MNs by photothermal ablation was convenient,environmentally friendly,and inexpensive.This technique provided a potential method for rapid and real-time diagnosis of multiple clinical bacterial infections and for monitoring microbial contamination of food in production sites.
基金Projects(2019NY-200,2020ZDLNY06-06,2020ZDLNY07-10)supported by the Key Research and Development Program of Shaanxi Province,ChinaProject(2019YFC1803604)supported by the National Key Research and Development Program of China。
文摘Lead(Pb)and zinc(Zn)are widely recognized as common environmental contaminants,contributing to soil degradation and posing risks to environmental health.Combining functional carbon-based materials with microorganisms has been considered as an effective and environmentally friendly strategy for remediating Pb/Zn-contaminated soil.However,there is still a lack of understanding the connection between heavy metal immobilization and plant responses,which hampers practical applications.Here,a 90-day pot experiment was conducted to investigate the integrated effects of biochar(WS700)and microorganisms including inorganic phosphate-solubilizing bacteria(IPSB)and sulfate reducing bacteria(SRB)on Pb and Zn synchronous immobilization and the physiological responses of Brassica rapa var.chinensis(Brassica).Compared with CK,bacteria-loaded biochar treatment declined the exchangeable Pb and Zn fraction by 94.69%−98.37%and 94.55%−99.52%,while increasing the residual state Pb and Zn by 75.50%−208.58%and 96.71%−110.85%,respectively.Three amendments enhanced Brassica growth by improving total chlorophyll content and superoxide dismutase(SOD)and peroxidase(POD)activities.The bacteria-loaded biochar treatment effectively regulated stomatal conductance and reduced intercellular CO_(2) concentration.Moreover,compared with CK,three amendments reduced MDA content by 28.84%,28.30%and 41.60%,respectively,under the high concentration of Pb and Zn.The findings demonstrated the significant role of bacterial-biochar consortia in immobilizing Pb and Zn and mitigating Pb and Zn-induced stress in plants by regulating photosynthetic characteristics and antioxidant enzyme activities.
基金The National Natural Science Foundation of China under contract Nos 42206126 and 42076044the Natural Science Foundation of Shandong Province under contract No.ZR2021QD099.
文摘Plate culture counting and strain isolation methods were utilized to assess the species richness and abundance of planktonic and attached bacteria on glass plates in the surface and bottom seawater of Qingdao Middle Harbor over a year,with monthly and quarterly sampling.Both species richness and bacterial numbers exhibited seasonal variations.Specifically,the abundance of attached bacteria and bacterioplankton peaked in June and July,corresponding to higher water temperatures in summer and autumn,while lower abundances were noted in January and December during cooler periods.Throughout the year,the species richness of attached bacteria consistently exceeded that of planktonic bacteria in both shallow and deep waters.Pseudoalteromonas emerged as the most prevalent genus among both planktonic and attached bacteria in surface and bottom seawater samples.Furthermore,the magnitude of changes in species richness and abundance for attached bacteria(0.66×10^(5)-15.85×10^(5)CFU/cm^(2))was greater than that observed for planktonic bacteria(0.58×10^(8)-5.33×10^(8)CFU/L).We propose that the attached bacterial populations,situated in limited microenvironments within the larger seawater ecosystem,exhibit heightened sensitivity to environmental fluctuations,resulting in more rapid shifts in population dynamics and lower ecological stability.The theoretical implications and potential applications of these findings warrant further investigation.
基金funded by the Key Research and Development Project of Xinjiang Uygur Autonomous Region (2024B02015-3)the Regional Coordinated Innovation Project (Shanghai Cooperation Organization Science and Technology Partnership Program) of Xinjiang Uygur Autonomous Region (2025E01024)
文摘Salt-tolerant bacteria associated with halophytes enhance plant resistance and adaptation to environmental stress.The purpose of this study was to investigate the diversity and plant-beneficial traits of bacteria associated with three halophytes in an arid land,Northwest China.The bacterial strains were isolated from the roots,shoots,rhizosphere,and bulk soil of three halophytes,i.e.,Salicornia europaea L.,Kalidium foliatum(Pall.)Moq.,and Suaeda aralocaspica(Bunge)Freitag&Schütze,collected from the saline soils near to the Wujiaqu City,Xinjiang,Northwest China.A total of 567 strains were isolated and identified from these three halophytes belonging to 4 phyla,6 classes,25 orders,36 families,and 66 genera,including 147 potential novel species.A total of 213 strains exhibited one or more plant growthpromoting properties,while 20 strains demonstrated multiple in vitro plant growth-promoting activities,including phosphate solubilization,nitrogen fixation,siderophore production,and production of hydrolytic enzymes such as protease and cellulase.Our findings showed that halophytes in the arid land harbor diverse bacteria with the potential to enhance plant growth and adaptability under challenging environmental conditions.
文摘Objective: This study assessed the effects of consuming acetic acid bacteria (Gluconacetobacter hansenii GK-1) for 12 weeks on fatigue induced by temporary mental stress. Methods: This randomized, double-blind, placebo-controlled, parallel-group study included 100 healthy male and female adults aged 20 - 64 years. Participants consumed either the G. hansenii GK-1 supplement (9 × 10⁹ cells/day) or a placebo daily for 12 weeks. The impact of temporary mental stress on fatigue in G. hansenii GK-1 was assessed using a Visual Analog Scale (VAS) before the study began and after 12 weeks of supplementation. Results: Subjective fatigue measured by Visual Analog Scale (VAS) showed a significant decrease in fatigue induced by temporary mental stress after 12 weeks of consumption in the G. hansenii GK-1 group compared with the placebo group. No adverse events were attributed to G. hansenii GK-1. These findings confirm that continuous oral ingestion of G. hansenii GK-1 by healthy Japanese adults reduces feelings of fatigue caused by temporary mental stress.
基金supported by the National Science Foundation of China (32001663)。
文摘Both the broad-spectrum bactericidal properties of disinfectants and the inhibitory effects of antibiotics pose potential threats to the activity,functionality,and probiotic properties of Lactid acid bacteria(LAB).Therefore,it is essential to systematically evaluate the tolerance of lactic acid bacteria to common disinfectants and antibiotics.This study assessed 60 LAB strains isolated from the fermented foods for their tolerance to seven disinfectants and nine antibiotics.The results indicated that,compared to pathogenic bacteria,most LAB exhibited stronger tolerance to disinfectants.Sub-inhibitory concentrations of disinfectants inhibited biofilm formation in most LAB,while sub-inhibitory concentrations of glutaraldehyde tended to promote biofilm formation.This suggests that commonly used disinfectants can eliminate pathogenic bacteria without killing LAB,providing guidance for disinfectant use.LAB were highly sensitive to ampicillin and chloramphenicol,while showing some tolerance to norfloxacin,polymyxin,and sulfamethoxazole.This indicates LAB have a notable antibiotic resistance profile,which includes both natural resistance characteristics and instances of acquired resistance,along with multiple drug resistance and cross-resistance between antibiotics and disinfectants.This study provides an important guidance for disinfection practices in industrial utilizing LAB,such as food and biomedicine,and offers a reference for the use of antibiotics.
