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783100.9818Integration of nanowire-confined electroporation of antibiotic-resistant bacteria and electroactivation of peracetic acid for eliminating intracellular resistance genes. Antimicrobial resistance is one of the most substantial challenges for global public health. To address the inefficient elimination of intracellular resistance genes (i-ARGs) in antibiotic-resistant bacteria (ARB) by peracetic acid (PAA) oxidation, we developed an integration strategy (NW-EP/EA) of nanowire-confined electroporation (NW-EP) of ARB cells and nanowire-confined electroactivation (NW-EA) of PAA with a sequential oxidation-reduction process. The locally enhanced electric field and electrocatalytic activity over NW tips prompted the formation of electroporation pores on ARB cells and the generation of reactive ⋅OH and RO⋅ radicals by PAA electroactivation. The NW-EP/EA with Pd-coated TiO(2)NW cathode with atomic H* evolution exhibited 0.6 -2.8-log higher i-ARG removal than the pristine TiO(2)NW cathode, especially achieving ∼5.0-log i-ARG removal (99.999 %) at 4.0 V and 2.0 mM PAA with ∼4.1-log synergistic effect and ∼10 times lower energy consumption as compared with the individual NW-EP (∼0.32-log and 52.1 %) and PAA (∼0.56-log and 74.4 %). For the sequential oxidation-reduction process, the electrooxidative activation of PAA on TiO(2)NW anode produced H(+) ions, ⋅OH and RO⋅ radicals for enlarging electroporation pores, and the generated H(+) ions promoted the evolution of atomic H* and electroreduction of PAA on subsequent Pd-TiO(2)NW cathode for further facilitating ARB cell damages, i-ARG leakage and degradation. The effective i-ARGs removal and HGT inhibition in tap water suggested the great application potentials of NW-EP/EA in the control of ARGs dissemination risks in drinking water.202540907311
872510.9810CuO nanoparticles facilitate soybean suppression of Fusarium root rot by regulating antioxidant enzymes, isoflavone genes, and rhizosphere microbiome. BACKGROUND: Fusarium root rot is a widespread soil-borne disease severely impacting soybean yield and quality. Compared to traditional fertilizers' biological and environmental toxicity, CuO nanoparticles (NPs) hold promise for disease control in a low dose and high efficiency manner. METHODS: We conducted both greenhouse and field experiments, employing enzymatic assays, elemental analysis, qRT-PCR, and microbial sequencing (16S rRNA, ITS) to explore the potential of CuO NPs for sustainable controlling Fusarium-induced soybean disease. RESULTS: Greenhouse experiments showed that foliar spraying of CuO NPs (10, 100, and 500 mg L(-1)) promoted soybean growth more effectively than EDTA-CuNa(2) at the same dose, though 500 CuO NPs caused mild phytotoxicity. CuO NPs effectively controlled root rot, while EDTA-CuNa(2) worsened the disease severity by 0.85-34.04 %. CuO NPs exhibited more substantial antimicrobial effects, inhibiting F. oxysporum mycelial growth and spore germination by 5.04-17.55 % and 10.24-14.41 %, respectively. 100 mg L(-1) CuO NPs was the optimal concentration for balancing soybean growth and disease resistance. Additionally, CuO NPs boosted antioxidant enzyme activity (CAT, POD, and SOD) in leaves and roots, aiding in ROS clearance during pathogen invasion. Compared to the pathogen control, 100 mg L(-1) CuO NPs upregulated the relative expression of seven isoflavone-related genes (Gm4CL, GmCHS8, GmCHR, GmCHI1a, GmIFS1, GmUGT1, and GmMYB176) by 1.18-4.51 fold, thereby enhancing soybean disease resistance in place of progesterone-receptor (PR) genes. Field trials revealed that CuO NPs' high leaf-to-root translocation modulated soybean rhizosphere microecology. Compared to the pathogen control, 100 mg L(-1) CuO NPs increased nitrogen-fixing bacteria (Rhizobium, Azospirillum, Azotobacter) and restored disease-resistant bacteria (Pseudomonas, Burkholderia) and fungi (Trichoderma, Penicillium) to healthy levels. Furthermore, 100 mg L(-1) CuO NPs increased beneficial bacteria (Pedosphaeraceae, Xanthobacteraceae, SCI84, etc.) and fungi (Trichoderma, Curvularia, Hypocreales, etc.), which negatively correlated with F. oxysporum, while recruiting functional microbes to enhance soybean yield. CONCLUSION: 100 mg L(-1) CuO NPs effectively promoting soybean growth and providing strong resistance against root rot disease by improving antioxidant enzyme activity, regulating the relative expression of isoflavone-related genes, increasing beneficial bacteria and fungi and restoring disease-resistant. Our findings suggest that CuO NPs offer an environmentally sustainable strategy for managing soybean disease, with great potential for green production.202540096759
786020.9803Enhanced removal of antibiotic-resistant bacteria and resistance genes by three-dimensional electrochemical process using MgFe(2)O(4)-loaded biochar as both particle electrode and catalyst for peroxymonosulfate activation. In this study, MgFe(2)O(4)-loaded biochar (MFBC) was used as a three-dimensional particle electrode to active peroxymonosulfate (EC/MFBC/PMS) for the removal of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs). The results demonstrated that, under the conditions of 1.0 mM PMS concentration, 0.4 g/L material dosage, 5 V voltage intensity, and MFBC preparation temperature of 600 °C, the EC/MFBC600/PMS system achieved complete inactivation of E. coli DH5α within 5 min and the intracellular sul1 was reduced by 81.5 % after 30 min of the treatment. Compared to EC and PMS alone treatments, the conjugation transfer frequency of sul1 rapidly declined by 92.9 % within 2 min. The cell membrane, proteins, lipids, as well as intracellular and extracellular ARGs in E. coli DH5α were severely damaged by free radicals in solution and intracellular reactive oxygen species (ROS). Furthermore, up-regulation was observed in genes associated with oxidative stress, SOS response and cell membrane permeability in E. coli DH5α, however, no significant changes were observed in functional genes related to gene conjugation and transfer mechanisms. This study would contribute to the underlying of PMS activation by three-dimensional particle electrode, and provide novel insights into the mechanism of ARB inactivation and ARGs degradation under PMS advanced oxidation treatment.202439197284
787530.9801Phenacetin enhanced the inorganic nitrogen removal performance of anammox bacteria naturally in-situ enriched system. Among the earliest synthetic antipyretic drugs, phenacetin (PNCT) could be used as the novel partial nitrification (PN) inhibitor to effectively inhibit nitrite-oxidizing bacteria (NOB). In practical application, the rapidly starting of PN could provide stable source of nitrite for anaerobic ammonium oxidation (anammox) process. However, impact of PNCT on anaerobic ammonia oxidizing bacteria (AnAOB) and its underlying mechanisms were not clear. In this research, totally 14 times of PNCT aerobic soaking treatment were performed in the AnAOB naturally enrichment system to improve total inorganic nitrogen removal efficiency (TINRE). After once of PNCT treatment, TINRE rose from 61.89 % to 79.93 %. After 14 times of PNCT treatment, NOB Nitrospira relative abundance decreased from 9.82 % to 0.71 %, though Candidatus Brocadia relative abundance also declined, it might gradually adjust to PNCT by converting the leading oligotype species. The activity and relative abundances of NOB were reduced by PNCT via decreasing the abundances of genes amoA and nxrB, enzymes NxrA and NxrB. Moreover, Candidatus Jettenia and Ca. Brocadia might be the potential host of qacH-01 and they played the crucial role in the shaping profile of antibiotic resistance genes (ARGs). The explosive propagation or transmission of ARGs might not take place after PNCT treatment.202439566627
786140.9800The removal of antibiotic resistant bacteria and genes and inhibition of the horizontal gene transfer by contrastive research on sulfidated nanoscale zerovalent iron activating peroxymonosulfate or peroxydisulfate. Antibiotic resistant bacteria (ARB) and the antibiotic resistance genes (ARGs) dissemination via plasmid-mediated conjugation have attracted considerable attentions. In this research, sulfidated nanoscale zerovalent iron (S-nZVI)/peroxymonosulfate (PMS) and S-nZVI/peroxydisulfate (PDS) process were investigated to inactivate ARB (Escherichia coli DH5α with RP4 plasmid, Pseudomonas. HLS-6 contains sul1 and intI1 on genome DNA sequence). S-nZVI/PMS system showed higher efficiency than S-nZVI/PDS on ARB inactivation. Thus, the optimal condition 28 mg/L S-nZVI coupled with 153.7 mg/L (0.5 mM) PMS was applied to remove both intracellular ARGs (iARGs) and ARB. The oxidative damage of ARB cell was systemically studied by cell viability, intracellular Mg(2+) levels, the changes of extracellular and internal structure, integrity of cell walls and membranes and enzymatic activities. S-nZVI/PMS effectively inactivated ARB (~7.32 log) within 15 min. These effects were greatly higher than those achieved individually. Moreover, removal efficiencies of iARGs sul1, intI1 and tetA were 1.52, 1.79 and 1.56 log, respectively. These results revealed that S-nZVI and PMS have a synergistic effect against ARB and iARGs. The regrowth assays illustrated that the ARB were effectively inactivated. By verifying the inhibitory impacts of S-nZVI/PMS treatment on conjugation transfer, this work highlights a promising alternative technique for inhibiting the horizontal gene transfer.202234482079
775150.9799A novel hypothermic strain, Pseudomonas reactans WL20-3 with high nitrate removal from actual sewage, and its synergistic resistance mechanism for efficient nitrate removal at 4 °C. Nitrate can be well removed by bacteria at 25-30 °C. However, nitrate removal almost ceases at temperatures lower than 5 °C. In this study, a novel hypothermic strain, Pseudomonas reactans WL20-3 exhibited an excellent aerobic nitrate removal ability at 4 °C. It had high capability for the removal of nitrate, total dissolved nitrogen (TDN), and dissolved organic carbon (DOC) at 4 °C, achieving removal efficiencies of 100%, 87.91%, and 97.48%, respectively. The transcriptome analysis revealed all genes involved in the nitrate removal pathway were significantly up-regulated. Additionally, the up-regulation of ABC transporter genes and down-regulation of respiratory chain genes cooperated with the nitrate metabolism pathway to resist low-temperature stress. In actual sewage, inoculated with WL20-3, the nitrate removal efficiency was found to be 70.70%. Overall, these findings demonstrated the impressive capacity of the novel strain WL20-3 to remove nitrate and provided novel insights into the synergistic resistance mechanism of WL20-3 at low temperature.202337369315
774560.9798Iron-modified biochar boosts anaerobic digestion of sulfamethoxazole pharmaceutical wastewater: Performance and microbial mechanism. The accumulation of volatile fatty acids (VFAs) caused by antibiotic inhibition significantly reduces the treatment efficiency of sulfamethoxazole (SMX) wastewater. Few studies have been conducted to study the VFAs gradient metabolism of extracellular respiratory bacteria (ERB) and hydrogenotrophic methanogen (HM) under high-concentration sulfonamide antibiotics (SAs). And the effects of iron-modified biochar on antibiotics are unknown. Here, the iron-modified biochar was added to an anaerobic baffled reactor (ABR) to intensify the anaerobic digestion of SMX pharmaceutical wastewater. The results demonstrated that ERB and HM were developed after adding iron-modified biochar, promoting the degradation of butyric, propionic and acetic acids. The content of VFAs reduced from 1166.0 mg L(-1) to 291.5 mg L(-1). Therefore, chemical oxygen demand (COD) and SMX removal efficiency were improved by 22.76% and 36.51%, and methane production was enhanced by 6.19 times. Furthermore, the antibiotic resistance genes (ARGs) such as sul1, sul2, intl1 in effluent were decreased by 39.31%, 43.33%, 44.11%. AUTHM297 (18.07%), Methanobacterium (16.05%), Geobacter (6.05%) were enriched after enhancement. The net energy after enhancement was 0.7122 kWh m(-3). These results confirmed that ERB and HM were enriched via iron-modified biochar to achieve high efficiency of SMX wastewater treatment.202337030222
787070.9797Hierarchical Bi(2)O(2)CO(3) wrapped with modified graphene oxide for adsorption-enhanced photocatalytic inactivation of antibiotic resistant bacteria and resistance genes. There is growing pressure for wastewater treatment plants to mitigate the discharge of antibiotic resistant bacteria (ARB) and extracellular resistance genes (eARGs), which requires technological innovation. Here, hierarchical Bi(2)O(2)CO(3) microspheres were wrapped with nitrogen-doped, reduced graphene oxide (NRGO) for enhanced inactivation of multidrug-resistant E. coli NDM-1 and degradation of the plasmid-encoded ARG (bla(NDM-1)) in secondary effluent. The NRGO shell enhanced reactive oxygen species (ROS) generation (•OH and H(2)O(2)) by about three-fold, which was ascribed to broadened light absorption region (red-shifted up to 459 nm) and decreased electron-transfer time (from 55.3 to 19.8 ns). Wrapping enhanced E. coli adsorption near photocatalytic sites to minimize ROS scavenging by background constituents, which contributed to the NRGO-wrapped microspheres significantly outperforming commercial TiO(2) photocatalyst. ROS scavenger tests indicated that wrapping also changed the primary inactivation pathway, with photogenerated electron holes and surface-attached hydroxyl radicals becoming the predominant oxidizing species with wrapped microspheres, versus free ROS (e.g., •OH, H(2)O(2) and •O(2)(-)) for bare microspheres. Formation of resistance plasmid-composited microsphere complexes, primary due to the π-π stacking and hydrogen bonding between the shell and nucleotides, also minimized ROS scavenging and kept free plasmid concentrations below 10(2) copies/mL. As proof-of-concept, this work offers promising insight into the utilization of NRGO-wrapped microspheres for mitigating antibiotic resistance propagation in the environment.202032679343
783280.9795Reduction of antibiotics and antibiotic resistance genes in simulated-sunlight-supported counter-diffusion bacteria-Algae biofilms: Interface properties and functional gene responses. A novel bacteria-algae symbiotic counter-diffusion biofilm system integrated within simulated-sunlight (designated UV-MABAR) was engineered to simultaneously address antibiotic residuals and antibiotic resistance genes (ARGs) while maintaining functional microbial consortia under simulated solar irradiation. The non-algal control system (UV-MABR) demonstrated elevated repulsion energy barriers accompanied by significant suppression of ATP synthase (p < 0.01) and DNA repair-related gene clusters, leading to biofilm homeostasis disruption and subsequent sulfamethoxazole (SMX) effluent accumulation peaking at 138.11±2.34 μg/L. In contrast, the UV-MABAR configuration exhibited dynamic quenching of tyrosine-associated fluorescence moieties within extracellular polymeric substances, thereby diminishing complexation potential with SMX aromatic rings and achieving 70.75 %±3.21 % abiotic photodegradation efficiency, which substantially curtailed ARG proliferation pathways, promoting a significant downregulation of sul1 (-1.9 log(2) fold-change) and sul2 (-1.1 log(2) fold-change) expression compared to conventional MABR controls. Besides, algal in UV-MABAR attenuated the irradiation-induced α-helix/(β-sheet + random coil) conformational shift, moderating biofilm matrix compaction. Crucially, algal proliferation up-regulated bacterial recA expression (1.7-fold increase), thereby preserving catabolic gene integrity and preventing endogenous substances release. These protective measures kept effluent concentrations of SMX, NH(4)(+)-N, total nitrogen, and COD in UV-MABAR at 19.84 μg/L, 3.88 mg/L, 12.76 mg/L, and 34.97 mg/L, respectively, during 150 days of operation.202540738088
787490.9794Phenacetin promoted the rapid start-up and stable maintenance of partial nitrification: Responses of nitrifiers and antibiotic resistance genes. Phenacetin (PNCT) belongs to one of the earliest synthetic antipyretics. However, impact of PNCT on nitrifying microorganisms in wastewater treatment plants and its potential microbial mechanism was still unclear. In this study, PN could be initiated within six days by PNCT anaerobic soaking treatment (8 mg/L). In order to improve the stable performance of PN, 21 times of PNCT aerobic soaking treatment every three days was conducted and PN was stabilized for 191 days. After PN was damaged, ten times of PNCT aerobic soaking treatment every three days was conducted and PN was recovered after once soaking, maintained over 88 days. Ammonia oxidizing bacteria might change the dominant oligotype to gradually adjust to PNCT, and the increase of abundance and activity of Nitrosomonas promoted the initiation of PN. For nitrite-oxidizing bacteria (NOB), the increase of Candidatus Nitrotoga and Nitrospira destroyed PN, but PN could be recovered after once aerobic soaking illustrating NOB was not resistant to PNCT. KEGG and COG analysis suggested PNCT might disrupt rTCA cycle of Nitrospira, resulting in the decrease of relative abundance of Nitrospira. Moreover, PNCT did not lead to the sharp increase of absolute abundances of antibiotic resistance genes (ARGs), and the risk of ARGs transmission was negligible.202438744392
7867100.9793The removal of antibiotic resistant bacteria and antibiotic resistance genes by sulfidated nanoscale zero-valent iron activating periodate: Efficacy and mechanism. Antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) have drawn much more attention due to their high risk on human health and ecosystem. In this study, the performance of sulfidated nanoscale zero-valent iron (S-nZVI)/periodate (PI) system toward ARB inactivation and ARGs removal was systematically investigated. The S-nZVI/PI system could realize the complete inactivation of 1 × 10(8) CFU/mL kanamycin, ampicillin, and tetracycline-resistant E. coli HB101 within 40 min, meanwhile, possessed the ability to remove the intracellular ARGs (iARGs) (including aphA, tetA, and tnpA) carried by E. coli HB101. Specifically, the removal of aphA, tetA, and tnpA by S-nZVI/PI system after 40 min reaction was 0.31, 0.47, and 0.39 log(10)copies/mL, respectively. The reactive species attributed to the E. coli HB101 inactivation were HO(•) and O(2)(•-), which could cause the destruction of E. coli HB101 morphology and enzyme system (such as superoxide dismutase and catalase), the loss of intracellular substances, and the damage of iARGs. Moreover, the influence of the dosage of PI and S-nZVI, the initial concentration of E. coli HB101, as well as the co-existing substance (such as HCO(3)(-), NO(3)(-), and humic acid (HA)) on the inactivation of E. coli HB101 and its corresponding iARGs removal was also conducted. It was found that the high dosage of PI and S-nZVI and the low concentration of E. coli HB101 could enhance the disinfection performance of S-nZVI/PI system. The presence of HCO(3)(-), NO(3)(-), and HA in S-nZVI/PI system showed inhibiting role on the inactivation of E. coli HB101 and its corresponding iARGs removal. Overall, this study demonstrates the superiority of S-nZVI/PI system toward ARB inactivation and ARGs removal.202337544470
7988110.9793Electrokinetic treatment at the thermophilic stage achieves more effective control of heavy metal resistance in swine manure composting. Excessive heavy metals (HMs) and metal resistance genes (MRGs) in manure pose significant environmental and human health risks. Our previous work proved enhanced control of antibiotic resistance and quality of swine manure composting with electrokinetic technology (EK). As a continuous study, EK treatments were further employed at typical stages of composting. The humification level increased significantly in EK treatments applied at the thermophilic stage (EK1) and throughout the whole composting period (EK2). The immobilization efficiency of heavy metals increased by 3.02 %-20.90 % for EK1, and 3.86 %-20.56 % for EK2, compared with the EK treatment applied at maturity stage (EK3). EK1 showed the highest ability to remove MRGs (29.38 %-87.13 %), while the abundance of potential host bacteria increased in EK2, raising potential transmission risk of MRGs. Furthermore, there was an elevated presence of bacteria associated with membrane transport as a response mechanism to HMs stress in EK1. Considering economic factors and environmental effects, EK treatment during the thermophilic stage was more effective in compost maturation, HMs passivation, as well as control of HMs resistance. This study provides an effective method to address HMs-related contamination with highly efficient maturation in swine manure composting.202540543370
7750120.9792Efficient removal of enrofloxacin in swine wastewater using eukaryotic-bacterial symbiotic membraneless bioelectrochemical system. A eukaryotic-bacterial symbiotic membraneless bioelectrochemical system (EBES) reactor with eukaryotic-bacteria symbiotic cathode was developed to treat swine wastewater containing enrofloxacin (ENR), which had high performance at ENR tolerance and operational stability. With ENR concentrations shifting from 2 to 50 mg/L, the removal efficiencies of ENR, chemical oxygen demand (COD) and NH(4)(+)-N always were higher than 95 %, and the maximum power output (≥343 mW/m(3)) could be achieved. At 20 mg/L ENR, the removal efficiencies of ENR, COD and NH(4)(+)-N respectively reached to 99.4 ± 0.1 %, 98.5 % ± 0.1 %, and 96.3 % ± 0.5 %, corresponding to the open circuit voltage and maximum power density (P(max)) of EBES were 851 mV and 455 mW/m(3). The community analyses showed that bacteria (Comamonas, Rhodobacter, Rhodococcus, and Vermiphilaceae et al.), algae (Chlorella) and fungi (Rozellomycota, Trebouxiophyceae, Exophiala, and Aspergillus et al.) at genus level were the dominate populations in the EBES, and their abundance increased with ENR concentration, suggesting they played key roles to remove ENR and another nutrient element. The low relative abundances (1.9 ×10(-7) to 1.1 ×10(-5) copies/g) of aac (6')-ib-cr, qnrA, qnrD, qnrS, and gyrA in effluent revealed that the present EBES reactor had superior capabilities in controlling antibiotic-resistance genes and antibiotic-resistant bacteria. Our trial experiments provided a novel way for antibiotic livestock wastewater treatment.202539938376
7866130.9791Inactivation of sulfonamide antibiotic resistant bacteria and control of intracellular antibiotic resistance transmission risk by sulfide-modified nanoscale zero-valent iron. The inactivation of a gram-negative sulfonamide antibiotic resistant bacteria (ARB) HLS.6 and removal of intracellular antibiotic resistance gene (ARG, sul1) and class I integrase gene (intI1) by nanoscale zero-valent iron (nZVI) and sulfide-modified nZVI (S-nZVI) with different S/Fe molar ratios were investigated in this study. The S-nZVI with high sulfur content (S/Fe = 0.05, 0.1, 0.2) was superior to nZVI and the treatment effect was best when S/Fe was 0.1. The ARB (2 × 10(7) CFU/mL) could be completely inactivated by 1.12 g/L of S-nZVI (S/Fe = 0.1) within 15 min, and the removal rates of intracellular sul1 and intI1 reached up to 4.39 log and 4.67 log at 60 min, respectively. Quenching experiments and flow cytometry proved that reactive oxygen species and adsorption were involved in the ARB inactivation and target genes removal. Bacterial death and live staining experiments and transmission electron microscopy showed that the ARB cell structure and intracellular DNA were severely damaged after S-nZVI treatment. This study provided a potential alternative method for controlling the antibiotic resistance in aquatic environment.202032585519
7836140.9790Efficient Degradation of Intracellular Antibiotic Resistance Genes by Photosensitized Erythrosine-Produced (1)O(2). Intracellular antibiotic resistance genes (iARGs) constitute the important part of wastewater ARGs and need to be efficiently removed. However, due to the dual protection of intracellular DNA by bacterial membranes and the cytoplasm, present disinfection technologies are largely inefficient in iARG degradation. Herein, we for the first time found that erythrosine (ERY, an edible dye) could efficiently degrade iARGs by producing abundant (1)O(2) under visible light. Seven log antibiotic-resistant bacteria were inactivated within only 1.5 min, and 6 log iARGs were completely degraded within 40 min by photosensitized ERY (5.0 mg/L). A linear relationship was established between ARG degradation rate constants and (1)O(2) concentrations in the ERY photosensitizing system. Surprisingly, a 3.2-fold faster degradation of iARGs than extracellular ARGs was observed, which was attributed to the unique indirect oxidation of iARGs induced by (1)O(2). Furthermore, ERY photosensitizing was effective for iARG degradation in real wastewater and other photosensitizers (including Rose Bengal and Phloxine B) of high (1)O(2) yields could also achieve efficient iARG degradation. The findings increase our knowledge of the iARG degradation preference by (1)O(2) and provide a new strategy of developing technologies with high (1)O(2) yield, like ERY photosensitizing, for efficient iARG removal.202337531556
7828150.9790Simultaneous elimination of antibiotic-resistant bacteria and antibiotic resistance genes by different Fe-N co-doped biochars activating peroxymonosulfate: The key role of pyridine-N and Fe-N sites. The coexistence of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB) in the environment poses a potential threat to public health. In our study, we have developed a novel advanced oxidation process for simultaneously removing ARGs and ARB by two types of iron and nitrogen-doped biochar derived from rice straw (FeN-RBC) and sludge (FeN-SBC). All viable ARB (approximately 10(8) CFU mL(-1)) was inactivated in the FeN-RBC/ peroxymonosulfate (PMS) system within 40 min and did not regrow after 48 h even in real water samples. Flow cytometry identified 96.7 % of dead cells in the FeN-RBC/PMS system, which verified the complete inactivation of ARB. Thorough disinfection of ARB was associated with the disruption of cell membranes and intracellular enzymes related to the antioxidant system. Whereas live bacteria (approximately 200 CFU mL(-1)) remained after FeN-SBC/PMS treatment. Intracellular and extracellular ARGs (tetA and tetB) were efficiently degraded in the FeN-RBC/PMS system. The production of active species, primarily •OH, SO(4)(•-) and Fe (IV), as well as electron transfer, were essential to the effective disinfection of FeN-RBC/PMS. In comparison with FeN-SBC, the better catalytic performance of FeN-RBC was mainly ascribed to its higher amount of pyridine-N and Fe(0), and more reactive active sites (such as CO group and Fe-N sites). Density functional theory calculations indicated the greater adsorption energy and Bader charge, more stable Fe-O bond, more easily broken OO bond in FeN-RBC/PMS, which demonstrated the stronger electron transfer capacity between FeN-RBC and PMS. To encapsulate, our study provided an efficient and dependable method for the simultaneous elimination of ARGs and ARB in water.202438669989
6083160.9790Bioactivity and genome analysis of Bacillus amyloliquefaciens GL18 isolated from the rhizosphere of Kobresia myosuroides in an alpine meadow. The unique eco-environment of the Qinghai-Tibet Plateau breeds abundant microbial resources. In this research, Bacillus amyloliquefaciens GL18, isolated from the rhizosphere of Kobresia myosuroides from an alpine meadow, and the antagonistic activity, bacteriostatic hydrolase activity, and low temperature, salt, and drought resistance of it were determined and analysed. The seedlings of Avena sativa were root-irrigated using bacteria suspensions (cell concentration 1 × 10(7) cfu/mL) of GL18, and the growth-promoting effect of GL18 on it was determined under cold, salt and drought stress, respectively. The whole genome of GL18 was sequenced, and its functional genes were analysed. GL18 presented significant antagonistic activity to Fusarium graminearum, Fusarium acuminatum, Fusarium oxysporum and Aspergillus niger (inhibition zone diameter > 17 mm). Transparent zones formed on four hydrolase detection media, indicating that GL18 secreted cellulase, protease, pectinase and β-1,3-glucanase. GL18 tolerated conditions of 10 °C, 11% NaCl and 15% PEG-6000, presenting cold, salt and drought resistance. GL18 improved the cold, salt and drought tolerance of A. sativa and it showed significant growth effects under different stress. The total length of the GL18 genome was 3,915,550 bp, and the number of coding DNA sequence was 3726. Compared with the clusters of orthologous groups of proteins, gene ontology and kyoto encyclopedia of genes and genomes databases, 3088, 2869 and 2357 functional genes were annotated, respectively. GL18 contained gene clusters related to antibacterial substances, functional genes related to the synthesis of plant growth-promoting substances, and encoding genes related to stress resistance. This study identified an excellent Bacillus strain and provided a theoretical basis for improving stress resistance and promoting the growth of herbages under abiotic stress.202438189906
7883170.9789Anammox biofilm system under the stress of Hg(II): Nitrogen removal performance, microbial community dynamic and resistance genes expression. The existence of heavy metals in wastewater has obtained more attention due to its high toxicity and non-degradability. In this study, we investigated the changes of anaerobic ammonium oxidation (Anammox) system under long-term invasion of Hg(Ⅱ). The results indicated that the total nitrogen removal efficiency (TNRE) dropped to around 55 % as Hg(Ⅱ) concentration went up to 20 mg L(-1). But the functional bacteria rapidly developed some resistant abilities and maintained a stable TNRE of 65 % till the end of test. The maximum relative expression fold change of merA, merB, merD and merR were 468.8476, 23.7383, 5.0321 and 15.2514 times, respectively. The high positive correlation between the expression abundance of metal resistance genes and the concentrations of Hg(Ⅱ) revealed the resistant mechanisms of microorganisms to heavy metals. Moreover, the protective strategy based on extracellular polymeric substances also contributed to the stability of Anammox system.202032315795
7863180.9788Mechanisms on the removal of gram-negative/positive antibiotic resistant bacteria and inhibition of horizontal gene transfer by ferrate coupled with peroxydisulfate or peroxymonosulfate. The existence of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) has been a global public environment and health issue. Due to the different cell structures, gram-positive/negative ARB exhibit various inactivation mechanisms in water disinfection. In this study, a gram-negative ARB Escherichia coli DH5α (E. coli DH5α) was used as a horizontal gene transfer (HGT) donor, while a gram-positive ARB Bacillus as a recipient. To develop an efficient and engineering applicable method in water disinfection, ARB and ARGs removal efficiency of Fe(VI) coupled peroxydisulfate (PDS) or peroxymonosulfate (PMS) was compared, wherein hydroxylamine (HA) was added as a reducing agent. The results indicated that Fe(VI)/PMS/HA showed higher disinfection efficiency than Fe(VI)/PDS/HA. When the concentration of each Fe(VI), PMS, HA was 0.48 mM, 5.15 log E. coli DH5α and 3.57 log Bacillus lost cultivability, while the proportion of recovered cells was 0.0017 % and 0.0566 %, respectively, and HGT was blocked. Intracellular tetA was reduced by 2.49 log. Fe(IV) and/or Fe(V) were proved to be the decisive reactive species. Due to the superiority of low cost as well as high efficiency and practicality, Fe(VI)/PMS/HA has significant application potential in ARB, ARGs removal and HGT inhibition, offering a new insight for wastewater treatment.202438615644
3546190.9787Mitigation of tetracycline resistance genes in silage through targeted lactic acid bacteria inoculation. The dissemination of antibiotic resistance genes (ARGs) in silage ecosystems poses a critical challenge to ecological stability and public health security. This investigation focuses on tetracycline resistance genes (TRGs), the most prevalent subtype of ARGs in silage, employing a targeted selection strategy for lactic acid bacteria (LAB) inoculants. From 226 isolated LAB strains, four candidates (LP1-3: Lactiplantibacillus plantarum; LC1: Lacticaseibacillus paracasei) demonstrating superior growth kinetics (OD(600) > 1.6 within 24 h) and rapid acidification capacity (pH < 3.9 within 24 h) were selected. Strains LP3 and LC1 exhibited minimal intrinsic TRGs content. These four strains reduced (p < 0.001) pH, ammonia-N concentration, and coliform bacterial counts of stylo silage. Metagenomic analysis revealed that strains LP1-3 promoted Lactiplantibacillus dominance (0.709-0.975 vs. 0.379-0.509 in the control), while LC1 enhanced Lacticaseibacillus abundance (0.449-0.612 vs. 0.002-0.013 in the control). Ensiling process downregulated 367 and upregulated 227 ARGs. Inoculation with the four LAB strains further enhanced the suppression of ARGs. Among the top 30 TRGs, 22 were reduced by strains LP1-3 and 20 by LC1. Quantitative PCR results showed that strains LP1-3 decreased (p < 0.05) the contents of tetA and tetG during 30 days fermentation. Among the TRGs increased, tetA(60), tetB(58), tet(T) were positively correlated with Lactiplantibacillus spp., tetA(58), tetB(60), tetA(46), tetB(46), tet(43) were significantly correlated with Lacticaseibacillus spp. (R > 0.4, p < 0.001). In conclusion, the fermentation process induced substantial ARGs profile modifications, LAB-mediated microbiome engineering enables TRGs suppression, providing a scientific foundation for precision silage management strategies targeting antimicrobial resistance mitigation.202541038354