BURKHOLDERIALES - Word Related Documents




#
Rank
Similarity
Title + Abs.
Year
PMID
012345
811000.9740Removal of chlortetracycline and antibiotic resistance genes in soil by earthworms (epigeic Eisenia fetida and endogeic Metaphire guillelmi). The impacts of two ecological earthworms on the removal of chlortetracycline (CTC, 0.5 and 15 mg kg(-1)) and antibiotic resistance genes (ARGs) in soil were explored through the soil column experiments. The findings showed that earthworm could significantly accelerate the degradation of CTC and its metabolites (ECTC) in soil (P < 0.05), with epigeic Eisenia fetida promoting degradation rapidly and endogeic Metaphire guillelmi exhibiting a slightly better elimination effect. Earthworms alleviated the abundances of tetR, tetD, tetPB, tetG, tetA, sul1, TnpA, ttgB and intI1 in soil, with the total relative abundances of ARGs decreasing by 35.0-44.2% in earthworm treatments at the 28th day of cultivation. High throughput sequencing results displayed that the structure of soil bacteria community was modified apparently with earthworm added, and some possible CTC degraders, Aeromonas, Flavobacterium and Luteolibacter, were promoted by two kinds of earthworms. Redundancy analysis demonstrated that the reduction of CTC residues, Actinobacteria, Acidobacteria and Gemmatimonadetes owing to earthworm stimulation was responsible for the removal of ARGs and intI1 in soil. Additionally, intI1 declined obviously in earthworm treatments, which could weaken the risk of horizontal transmission of ARGs. Therefore, earthworm could restore the CTC-contaminated soil via enhancing the removal of CTC, its metabolites and ARGs.202133798888
637910.9739Shotgun metagenome guided exploration of anthropogenically driven resistomic hotspots within Lonar soda lake of India. Anthropogenic activities mediated antibiotic resistance genes (ARGs) in the pristine aquatic bodies (lakes) is raising concern worldwide. Long read shotgun sequencing was used to assess taxonomic diversity, distribution of ARGs and metal resistance genes (MRGs) and mobile genetic elements (MGEs) in six sites within hypersaline Lonar soda lake (India) prone to various anthropogenic activities. Proteobacteria and Euryarchaeota were dominant phyla under domain Bacteria and Archaea respectively. Higher abundance of Bacteroidetes was pragmatic at sites 18LN5 and 18LN6. Functional analysis indicated 26 broad-spectrum ARGs types, not reported earlier in this ecosystem. Abundant ARG types identified were multidrug efflux, glycopepetide, bacitracin, tetracycline and aminogylcoside resistance. Sites 18LN1 and 18LN5 depicted 167 and 160 different ARGs subtypes respectively and rpoB2, bcrA, tetA(48), mupA, ompR, patA, vanR and multidrug ABC transporter genes were present in all samples. The rpoB2 gene was dominant in 18LN1, whereas bcrA gene in 18LN2-18LN6 sites. Around 24 MRGs types were detected with higher abundance of arsenic in 18LN1 and copper in 18LN2-18LN6, signifying metal contamination linked to MRGs. The bacterial taxa Pseudomonas, Thioalkalivibrio, Burkholderia, Clostridium, Paenibacillus, Bacillus and Streptomyces were significantly associated with ARGs. This study highlights the resistomic hotspots in the lake for deploying policies for conservation efforts.202032155479
810520.9728Refluxing mature compost to replace bulking agents: A low-cost solution for suppressing antibiotic resistance genes rebound in sewage sludge composting. Antibiotic resistance genes (ARGs) rebounding during composting cooling phase is a critical bottleneck in composting technology that increased ARGs dissemination and application risk of compost products. In this study, mature compost (MR) was used as a substitute for rice husk (RH) to mitigate the rebound of ARGs and mobile genetic elements (MGEs) during the cooling phase of sewage sludge composting, and the relationship among ARGs, MGEs, bacterial community and environmental factors was investigated to explore the key factor influencing ARGs rebound. The results showed that aadD, blaCTX-M02, ermF, ermB, tetX and vanHB significantly increased 4.76-32.41 times, and the MGEs rebounded by 38.60% in the cooling phase of RH composting. Conversely, MR reduced aadD, tetM, ermF and ermB concentrations by 59.49-98.58%, and reduced the total abundance of ARGs in the compost product by 49.32% compared to RH, which significantly restrained ARGs rebound. MR promoted secondary high temperature inactivation of potential host bacteria, including Ornithinibacter, Rhizobiales and Caldicoprobacter, which could harbor aadE, blaCTX-M02, and blaVEB. It also reduced the abundance of lignocellulose degrading bacteria of Firmicutes, which were potential hosts of aadD, tetX, ermF and vanHB. Moreover, MR reduced moisture and increased oxidation reduction potential (ORP) that promoted aadE, tetQ, tetW abatement. Furthermore, MR reduced 97.36% of total MGEs including Tn916/1545, IS613, Tp614 and intI3, which alleviated ARGs horizontal transfer. Overall finding proposed mature compost reflux as bulking agent was a simple method to suppress ARGs rebound and horizontal transfer, improve ARGs removal and reduce composting plant cost.202539798649
774330.9720Integrated meta-omics study on rapid tylosin removal mechanism and dynamics of antibiotic resistance genes during aerobic thermophilic fermentation of tylosin mycelial dregs. For efficient treatment of tylosin mycelial dregs (TMDs), rapid tylosin removal mechanism and dynamics of ARGs during TMDs fermentation were investigated using integrated meta-omics (genomics, metaproteomics and metabolomics) and qPCR approaches. The results showed that over 86% of tylosin was degraded on day 7 regardless of the type of bulking agents. The rapid removal of tylosin was mainly attributed to de-mycarose reaction (GH3) and esterase hydrolysis (C7MYQ7) of Saccharomonospora, and catalase-peroxidase oxidation of Bacillus (A0A077JB13). In addition, the moisture content and mobile genetic elements were vital to control the rebound of ARGs. The removal efficiency of antibiotic resistant bacteria (Streptomyces, Pseudomonas, norank_f__Sphingobacteriaceae, and Paenalcaligenes) and Intl1 (98.8%) in fermentation treatment TC21 with corncob as the bulking agent was significantly higher than that in other three treatments (88.3%). Thus, appropriate bulking agents could constrain the abundance of antibiotic resistant bacteria and Intl1, which is crucial to effectively reduce the resistance.202235307520
810740.9718Effects of micron-scale zero valent iron on behaviors of antibiotic resistance genes and pathogens in thermophilic anaerobic digestion of waste activated sludge. This work investigated the metagenomics-based behavior and risk of antibiotic resistance genes (ARGs), and their potential hosts during thermophilic anaerobic digestion (TAD) of waste activated sludge, enhanced by micron-scale zero valent iron (mZVI). Tests were conducted with 0, 25, 100, and 250 mg mZVI/g total solids (TS). Results showed that up to 7.3% and 4.8% decrease in ARGs' abundance and diversity, respectively, were achieved with 100 mg mZVI/g TS. At these conditions, ARGs with health risk in abundance and human pathogenic bacteria (HPB) diversity were also decreased by 8.3% and 3.6%, respectively. Additionally, mZVI reduced abundance of 72 potential pathogenic supercarriers for ARGs with high health risk by 2.5%, 5.0%, and 6.1%, as its dosage increased. Overall, mZVI, especially at 100 mg/g TS, can mitigate antibiotic resistance risk in TAD. These findings are important for better understanding risks of ARGs and their pathogenic hosts in ZVI-enhanced TAD of solid wastes.202336931448
638150.9716Occurrence and distribution of antibiotic resistance genes in Elymus nutans silage from different altitudes on the Qinghai-Tibetan Plateau. INTRODUCTION: Antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB) have attracted more attentions in fermented feed recently. However, little information is available on the occurrence and distribution of ARGs in ensiled forages in the alpine region of the Qinghai-Tibetan plateau (QTP) with an extremely harsh environment. METHODS: The study investigated the distribution and spread mechanism of ARB and ARGs in Elymus nutans silage along 2600 m (low), 3600 m (medium) and 4600 m (high) altitude in the QTP. RESULTS: The major ARG types in Elymus nutans silage were multidrug, aminoglycoside, bacitracin, beta-lactam and polymyxin, while tnpA and IS91 were the dominant mobile genetic elements (MGEs) subtypes in the Elymus nutans silage. The dominant ARGs were mainly carried by Pantoea, Enterobacter, Serratia, and Lelliottia. Although altitudinal gradient had no influence on the diversity or abundance of other ARGs and MGEs in the Elymus nutans silage (p > 0.05), the network co-occurrence patterns among ARGs, MGEs, and bacteria in high-altitude silage were more complex than that in low- and medium-altitude silages. The dominant clinical ARGs in the alpine silage were bacA and acrF, and the abundance of clinical ARGs decreased with prolonged fermentation time. DISCUSSION: This study provides important data on the status of ARGs in ensiled forage from the alpine region of the QTP.202540458713
811160.9713Effect of alkaline-thermal pretreatment on biodegradable plastics degradation and dissemination of antibiotic resistance genes in co-compost system. Biodegradable plastics (BDPs) are an eco-friendly alternative to traditional plastics in organic waste, but their microbial degradation and impact on antibiotic resistance genes (ARGs) transmission during co-composting remain poorly understood. This study examines how alkaline-thermal pretreatment enhances BDPs degradation and influences the fate of ARGs and mobile genetic elements (MGEs) in co-composting. Pretreatment with 0.1 mol/L NaOH at 100℃ for 40 minutes increased the surface roughness and hydrophilicity of BDPs while reducing their molecular weight and thermal stability. Incorporating pretreated BDPs film (8 g/kg-TS) into the compost reduced the molecular weight of the BDPs by 59.70 % during the maturation stage, facilitating compost heating and prolonging the thermophilic stage. However, incomplete degradation of BDPs releases numerous smaller-sized microplastics, which can act as carriers for microorganisms, facilitating the dissemination of ARGs across environments and posing significant ecological and public health risks. Metagenomic analysis revealed that pretreatment enriched plastic-degrading bacteria, such as Thermobifida fusca, on BDPs surfaces and accelerated microbial plastic degradation during the thermophilic stage, but also increased ARGs abundance. Although pretreatment significantly reduced MGEs abundance (tnpA, IS19), the risk of ARGs dissemination remained. Three plastic-degrading bacteria (Pigmentiphaga sp002188465, Bacillus clausii, and Bacillus altitudinis) were identified as ARGs hosts, underscoring the need to address the risk of horizontal gene transfer of ARGs associated with pretreatment in organic waste management.202539970645
807070.9713Impacts of combined pollution under gradient increasing and gradient decreasing exposure modes on activated sludge: Microbial communities and antibiotic resistance genes. The responses of microbial communities and antibiotic resistance genes (ARGs) to azithromycin and copper combined pollution under gradient increasing (from 0.5 to 10 mg/L) and decreasing exposure (from 10 to 0.5 mg/L) modes were investigated. Nitrification was inhibited more obviously under gradient increasing exposure mode. Responses of archaeal community and function structure were more obvious than bacteria under both exposure modes. The dominant bacterial and archaeal compositions (Hyphomicrobium, Euryarchaeota, etc.) were affected by two exposure modes, except some rare archaea (Methanoregula and Methanosarcina). There were more positive correlations between bacteria and archaea, and Nitrospira was keystone genus. Ammonia-oxidizing archaea (0.37-3.06%) and complete ammonia oxidizers (Nitrospira_ENR4) were enriched, and Nitrososphaera_viennensis was closely related to denitrifying genes (napA/B, nosZ, etc.). 50 ARG subtypes were detected and specific ARG subtypes (aac, ImrA, etc.) proliferated in two exposure modes. Bacteria and archaea were common hosts for 24 ARGs and contributed to their shifts.202234921920
805480.9713Effects of nanoscale zero-valent iron on the performance and the fate of antibiotic resistance genes during thermophilic and mesophilic anaerobic digestion of food waste. The effects of nanoscale zero-valent iron (nZVI) on the performance of food waste anaerobic digestion and the fate of antibiotic resistance genes (ARGs) were investigated in thermophilic (TR) and mesophilic (MR) reactors. Results showed that nZVI enhanced biogas production and facilitated ARGs reduction. The maximum CH(4) production was 212.00 ± 4.77 ml/gVS with 5 g/L of nZVI in MR. The highest ARGs removal ratio was 86.64 ± 0.72% obtained in TR at nZVI of 2 g/L. nZVI corrosion products and their contribution on AD performance were analyzed. The abundance of tetracycline genes reduced significantly in nZVI amended digesters. Firmicutes, Chloroflexi, Proteobacteria and Spirochaetes showed significant positive correlations with various ARGs (p < 0.05) in MR and TR. Redundancy analysis indicated that microbial community was the main factor that influenced the fate of ARGs. nZVI changed microbial communities, with decreasing the abundance bacteria belonging to Firmicutes and resulting in the reduction of ARGs.201931505392
774490.9712Dynamics and removal mechanisms of antibiotic and antibiotic resistance genes during the fermentation process of spectinomycin mycelial dregs: An integrated meta-omics study. Antibiotic mycelial dregs (AMDs) have been listed as industrial hazardous wastes. With the aim of reducing the environmental risk, the integrated-omics and qPCR approaches were used to reveal the dynamics and removal mechanisms of antibiotic and antibiotic resistance genes (ARGs) during the fermentation of different spectinomycin mycelial dregs (SMDs). The results showed that the removal efficiency of antibiotic in the fermentation of high moisture SMDs reached up to 98%. The high abundance of aadA1 gene encoded by Streptomyces, Lactobacillus, and Pseudomonas was associated with the efficient degradation of spectinomycin, and the inactivating enzymes secreted by degradative bacteria were identified. Furthermore, the dominant microbiota was impacted by moisture content significantly under high temperature environments. In the fermentation of low moisture SMDs, Saccharopolyspora was the dominant microbiota which secreted S8 endopeptidase, M14, M15, S10, S13 carboxypeptidases, M1, M28, S15 aminopeptidases, and antioxidant enzymes, while in the fermentation of high moisture SMDs, Bacillus and Cerasibacillus were dominant genera which mainly secreted S8 endopeptidase and antioxidant enzymes. The abundance of ARGs and mobile genetic elements decreased significantly at thermophilic phase, with maximum drops of 93.7% and 99.9%, respectively. Maintaining moisture content below 30% at the end phase could prevent the transmission of ARGs effectively.202234396972
6387100.9711Insights into the Evolutionary and Ecological Roles of Bathyarchaeia in Arsenic Detoxification. Arsenic (As) is a prevalent toxic element, posing significant risks to organisms, including microbes. While microbial arsenic detoxification has been extensively studied in bacteria, archaeal mechanisms remain understudied. Here, we investigated arsenic resistance genes in Bathyarchaeia, one of the most abundant archaeal lineages on Earth. Comprehensive genomic analysis of 318 Bathyarchaeia representatives revealed a widespread distribution of arsenic resistance genes, with 60% of genomes harboring genes for arsenate reduction (arsR1 and arsC2), arsenite methylation (arsM), and arsenic transport (acr3, arsP, and arsB). Phylogenetic analysis revealed that these genes are widely distributed across 14 archaeal phyla, including Asgardarchaeota, Thermoproteota, and Thermoplasmatota, with close evolutionary relationships among these archaeal lineages. In situ investigation of sediment columns and laboratory microcosm experiments demonstrated a strong positive correlation between Bathyarchaeia abundance and arsenic concentrations, suggesting their adaptation to arsenic-rich environments. Molecular dating analysis placed the emergence of Bathyarchaeia at approximately 3.01 billion years ago, with the evolution of their arsenic resistance mechanisms closely tracking major geological events, including the Great Oxidation Event (2.4-2.1 Gya), Huronian Glaciation (2.29-2.25 Gya), and Cryogenian Glaciation (∼700 Mya). Our findings highlight the critical role of Archaea in the arsenic cycle and provide insights into the evolutionary history of arsenic resistance associated with paleogeochemical changes in Bathyarchaeia.202540921195
7746110.9711Phosphate-modified calamus-based biochar filler enhanced constructed wetland mitigating antibiotic resistance risks: insight from metagenomics. In this study, an innovative phosphate-modified calamus-biochar (PBC) filler with high antibiotic adsorption capacity was developed to enhance constructed wetlands (CWs) wastewater treatment. Results showed that the erythromycin (ERY) and sulfamethoxazole (SMX) removal efficiency of PBC-CW was 86.5 % and 84.0 %, which was 2-fold higher than those of the blank group. Metagenomic analysis found that the ERY and SMX would significantly promote the increase in abundance of antibiotic resistance genes (ARGs), mobile genetic elements (MGEs) and virulence factor genes (VFGs). Compared to blank group, the abundances of ARGs, MGEs and VFGs were reduced by 67.2 %, 33.3 % and 11.1 % in PBC-CW. Among them, the abundance of sulfonamide and MLS, which were key genes to resistance to SMX and ERY, respectively, were reduced by 71.8 % and 63.1 % in PBC-CW. Moreover, these persistent ARG subtypes, detected simultaneously in all the samples, reduced the total abundance by 44.8 %. In addition, microbial community analysis found that the sum abundance of Arenimonas, Chryseobacterium and Hydrogenophaga, which were suggested as potential antibiotic-resistant bacteria (ARB) via correlation analysis, were significantly decreased from 1.54 % in blank group to 0.23 % in PBC group. Moreover, Chryseobacterium and Hydrogenophaga were positively correlated with VFGs, they could be pathogens with resistance genes. Therefore, PBC-CW could effectively reduce the abundance of ARGs and pathogenic microorganisms, thereby improving water security.202540845656
7167120.9711Occurrence and distribution of antibiotic pollution and antibiotic resistance genes in seagrass meadow sediments based on metagenomics. Seagrass meadows are one of the most important coastal ecosystems that provide essential ecological and economic services. The contamination levels of antibiotic and antibiotic resistance genes (ARGs) in coastal ecosystems are severely elevated owing to anthropogenic disturbances, such as terrestrial input, aquaculture effluent, and sewage discharge. However, few studies have focused on the occurrence and distribution of antibiotics and their corresponding ARGs in this habitat. Thus, we investigated the antibiotic and ARGs profiles, microbial communities, and ARG-carrying host bacteria in typical seagrass meadow sediments collected from Swan Lake, Caofeidian shoal harbor, Qingdao Bay, and Sishili Bay in the Bohai Sea and northern Yellow Sea. The total concentrations of 30 detected antibiotics ranged from 99.35 to 478.02 μg/kg, tetracyclines were more prevalent than other antibiotics. Metagenomic analyses showed that 342 ARG subtypes associated with 22 ARG types were identified in the seagrass meadow sediments. Multidrug resistance genes and RanA were the most dominant ARG types and subtypes, respectively. Co-occurrence network analysis revealed that Halioglobus, Zeaxanthinibacter, and Aureitalea may be potential hosts at the genus level, and the relative abundances of these bacteria were higher in Sishili Bay than those in other areas. This study provided important insights into the pollution status of antibiotics and ARGs in typical seagrass meadow sediments. Effective management should be performed to control the potential ecological health risks in seagrass meadow ecosystems.202438782270
7983130.9710Insights into the associations of copper and zinc with nitrogen metabolism during manure composting with shrimp shell powder. The application of shrimp shell powder (SSP) in manure composting can promote the maturation of compost and reduce the associated environmental risk. This study investigated the response of adding SSP at different levels (CK: 0, L: 5%, M: 10%, and H: 15%) on heavy metal resistance genes (MRGs), nitrogen functional genes, enzymes, and microorganisms. SSP inhibited nitrification and denitrification via decreasing the abundances of functional genes and key enzymes related to Cu, Zn, and MRGs. The nitrate reductase and nitrous-oxide reductase in the denitrification pathway were lower under H. Phylogenetic trees indicated that Burkholderiales sp. had strong relationships with OTU396 and OTU333, with important roles in the nitrogen cycle and plant growth. Redundancy analysis and structural equation modeling showed the complex response between heavy metal and nitrogen that bio-Cu and bio-Zn had positive significantly relationships with nirK-type and amoA-type bacteria, and amoA-type bacteria might be hotspot of cueO.202234861387
6940140.9710Higher spreading risk of antibacterial biocide and heavy metal resistance genes than antibiotic resistance genes in aerobic granular sludge. Metagenomic approach was applied to simultaneously reveal the antibiotic resistance genes (ARGs) and antibacterial biocide & metal resistance genes (BMRGs), and the corresponding microbial hosts with high mobility during aerobic granular sludge (AGS) formation process. The results showed that the relative abundance of BMRGs was 88-123 times that of ARGs. AGS process was easier to enrich BMRGs, leading to a greater risk of drug resistance caused by BMRGs than that by ARGs. The enrichments of ARGs and BMRGs in AGS were closely related to several enhanced microbial metabolisms (i.e., cell motility, transposase and ATP-binding cassette transporters) and their corresponding regulatory genes. Several enhanced KEGG Orthologs (KO) functions, such as K01995, K01996, K01997 and K02002, might cause a positive impact on the spread of ARGs and BMRGs, and the main contributors were the largely enriched glycogens accumulating organisms. The first dominant ARGs (adeF) was carried by lots of microbial hosts, which might be enriched and propagated mainly through horizontal gene transfer. Candidatus Competibacter denitrificans simultaneously harbored ARG (cmx) and Cu related RGs (corR). Many enriched bacteria contained simultaneously multiple BMRGs (copR and corR) and mobile genetic elements (integrons and plasmids), granting them high mobility capabilities and contributing to the spread of BMRGs. This study might provide deeper understandings of the proliferation and mobility of ARGs and BMRGs, importantly, highlighted the status of BMRGs, which laid the foundation for the controlling widespread of resistance genes in AGS.202235489476
7136150.9710Insights into the effects of haze pollution on airborne bacterial communities and antibiotic resistance genes in fine particulate matter. Fine particulate matter (PM(2.5)) is a key component of haze pollution and poses a substantial threat to human health. However, airborne bacteria and antibiotic-resistance genes (ARGs), which are important biological components of PM(2.5), have received less attention. In this study, we investigated the combined effects of haze on airborne bacteria and ARGs in PM(2.5). Overall, during haze days, high concentrations of airborne bacteria (haze: 4782.24 ± 2689.85 cells/m(3); non-haze: 2866.00 ± 1753.95 cells/m(3)) were observed with unique bacterial community structures. At the genus level, Microvirga, Arthrobacter, and JG30-KF-CM45 were identified as the bacterial biomarkers of haze days. Neutral processes contributed more to the establishment of airborne bacterial communities on haze days (R(2) = 0.724) than that on non-hazy days (R(2) = 0.338). The pathogenicity of bacterial communities per unit volume of air was significantly higher during haze days (169.36 ± 8.36 cell/m(3)) than that during non-haze days (112.66 ± 5.92 cell/m(3)) (p < 0.05). Redundancy analysis indicated that relatively stable atmospheric conditions and high concentrations of water-soluble ions (Na(+), Mg(2+), Ca(2+), and F(-)), metals (Cd, As, Mn, and Cr), and carbonaceous fractions (elemental carbon) in PM(2.5) play critical roles in shaping the bacterial community during haze days. On haze days, airborne ARGs exhibited unique distribution characteristics and network structures with dominant bacteria. This study highlighted the impact of haze days on airborne bacteria and ARGs on PM(2.5) and provides a reference for managing the risks of bioaerosols.202540409396
8010160.9709Co-occurrence pattern of ARGs and N-functional genes in the aerobic composting system with initial elevated temperature. Animal manure is known to harbor antibiotic resistance genes (ARGs). Aerobic composting is a prevalent cost-effective and sustainable method to treat animal waste. However, the effect of initially elevated temperature on antibiotic resistome during the composting process is unclear. In this study composting was subjected to initial external heating (EHC) for a period of 5 days compared to conventional composting (CC). After composting ARGs abundance was significantly reduced by 2.43 log in EHC and 1.95 log in CC. Mobile genetic elements (MGEs) also exhibited a reduction of 1.95 log in EHC and 1.49 log in CC. However, during the cooling phase, the genes resisting macrolide lincosamide and streptogramin B (MLSB) rebounded by 0.04 log in CC. The potential human pathogenic bacteria Pseudomonas (41.5-61.5%) and Actinobacteria (98.4-98.8%) were significantly reduced in both treatments and the bulk of targeted antibiotics were eliminated by 80.74% in EHC and 68.98% in CC. ARGs and N-functional genes (NFGs), mainly denitrification genes, were carried by the same microbial species, such as Corynebacterium sp. and Bacillus sp., of the dominant phylum. Redundancy analysis (RDA) revealed that CC microbial communities played a key role in the enrichment of ARGs while in EHC the variation of ARGs was attributed to the composting temperature. The number of high-risk ARGs was also lower in EHC (4) compared with CC (6) on day 30. These results provide insight into the effects of an initially enhanced temperature on ARGs removal and the relationship between ARGs and NFGs during the composting process.202337229868
7941170.9709Microplastics accelerate nitrification, shape the microbial community, and alter antibiotic resistance during the nitrifying process. Microplastics (MPs) and antibiotic resistance genes (ARGs) are both emerging pollutants that are frequently detected in wastewater treatment plants. In this study, the effects of various MPs, including polyethylene (PE), polyvinyl chloride (PVC), and biodegradable polylactic acid (PLA), on nitrification performance, dominant microbial communities, and antibiotic resistance during nitrification were investigated. The results revealed that the addition of MPs increased the specific ammonia oxidation rate and specific nitrate production rate by 15.2 % - 15.5 % and 8.0 % - 11.6 %, respectively, via enrichment of nitrifying microorganisms, Nitrospira and Nitrosomonas. Moreover, ARGs were selectively enriched in nitrifying sludge and microplastic biofilms under stress from different MPs. Compared with PE-MPs (23.9 %) and PVC-MPs (21.4 %), exposure to PLA-MPs significantly increased intI1 abundance by 51.6 %. The results of the variance decomposition analysis implied that MPs and the microbial community play important roles in the behavior of ARGs. Network analysis indicated that Nitrosomonas and potentially pathogenic bacteria emerged as possible hosts, harboring ARGs and intI1 genes in the nitrifying sludge and microplastic biofilms. Critically, PLA-MPs were found to enrich both ARGs and potential pathogenic bacteria during nitrification, which should be considered in their promotion of application processes due to their biodegradability.202539740624
8050180.9709Effects of antibiotics on corncob supported solid-phase denitrification: Denitrification and antibiotics removal performance, mechanism, and antibiotic resistance genes. Solid-phase denitrification (SPD) has been used in wastewater treatment plant effluent to enhance nitrate removal, and antibiotics co-existing in the effluent is a common environmental problem. In this study, it was systematically investigated the effect of single trace sulfamethoxazole (SMX)/trimethoprim (TMP) and their mixture on microbial denitrification performance, the antibiotics removal, and antibiotics resistance genes (ARGs) in corncob supported SPD system. The average denitrification rate was improved by 46.90% or 61.09% with single 50 µg/L SMX or TMP, while there was no significant inhibition with mixed SMX and TMP. The abundance of dominant denitrifiers (Comamonadaceae family and Azospia) and fermentation bacteria (Ancalomicrobium) were consistent with the denitrification performance of different antibiotics groups. Single SMX and TMP achieved relatively higher denitrification gene and enzyme abundance. Mixed SMX and TMP improved the denitrification gene copies, but they reduced the key denitrification enzymes except for EC 1.7.7.2. Additionally, the removal efficiency of TMP (56.70% ± 3.18%) was higher than that of SMX (25.44% ± 2.62%) in single antibiotic group, and the existence of other antibiotics (i.e. SMX or TMP) had no significant impact on the TMP or SMX removal performance. Biodegradation was the main removal mechanism of SMX and TMP, while sludge and corncob adsorption contributed a little to their removal. SMX had the risk of sulfanilamide resistance genes (SRGs) dissemination. Furthermore, network analysis indicated that Niveibacterium and Bradyrhizobium were the potential hosts of SRGs, which promoted the horizontal transmission of ARGs.202337032040
7164190.9708Anthropogenic pressures amplify high-risk antibiotic resistome via co-selection among biocide resistance, virulence, and antibiotic resistance genes in the Ganjiang River basin: Drivers diverge in densely versus sparsely populated reaches. As the largest river in the Poyang Lake system, the Ganjiang River faces escalating anthropogenic pressures that amplify resistance gene dissemination. This study integrated antibiotic resistance genes (ARGs), biocide resistance genes (BRGs), and virulence factor genes (VFGs) to reveal their co-selection mechanisms and divergent environmental drivers between densely (DES) and sparsely populated (SPAR) regions of the Ganjiang River basin. The microbial and viral communities and structures differed significantly between the DES and SPAR regions (PERMANOVA, p < 0.001). Midstream DES areas were hotspots for ARGs/BRGs/VFGs enrichment, with peak enrichment multiples reaching 10.2, 5.7, and 5.9-fold respectively. Procrustes analysis revealed limited dependence of ARGs transmission on mobile genetic elements (MGEs) (p > 0.05). Separately, 74 % of dominant ARGs (top 1 %) showed strong correlations with BRGs (r(2) = 0.973, p < 0.01) and VFGs (r(2) = 0.966, p < 0.01) via co-selection. Pathogenic Pseudomonas spp. carrying multidrug-resistant ARGs, BRGs, and adhesion-VFGs were identified as high-risk vectors. In SPAR areas, anthropogenic pressure directly dominated ARGs risk (RC = 54.2 %, β = 0.39, p < 0.05), with biological factors as secondary contributors (RC = 45.8 %, β = 0.33, p < 0.05). In contrast, DES regions showed anthropogenic pressure exerting broader, enduring influences across microorganisms, physicochemical parameters, and biological factors, escalating ARGs risks through diverse pathways, with BRGs/VFGs acting as direct drivers. This study proposes establishing a risk prevention system using BRGs and pathogenic microorganisms as early-warning indicators.202540858019