# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 7055 | 0 | 0.9875 | Characterization of antibiotic resistance genes and bacterial community in selected municipal and industrial sewage treatment plants beside Poyang Lake. Sewage treatment plants (STPs) are significant reservoirs of antibiotic resistance genes (ARGs) and antibiotic-resistant bacteria (ARB). Municipal STPs (MSTPs) and industrial STPs (ISTPs) are the two most important STP types in cities. In this study, the ARGs, mobile genetic elements (MGEs), and bacterial communities of selected STPs, including two MSTPs and one ISTP, in the vicinity of Poyang Lake were comprehensively investigated through high-throughput qPCR and high-throughput Illumina sequencing. The results showed that the profiles of ARGs, MGEs and bacteria differed between the ISTP and the two MSTPs, most likely due to differences in influent water quality, such as the Pb that characterized in the ISTP's influent. The longer hydraulic retention times (HRTs) of the two MSTPs than of the ISTP may also have accounted for the different profiles. Thus, a prolonged HRT in the CASS process seems to allow a more extensive removal of ARGs and bacteria in ISTPs with similar treatment process. By providing comprehensive insights into the characteristics of ARGs, MGEs and the bacterial communities of the selected MSTPs and ISTP, our study provides a scientific basis for controlling the propagation and diffusion of ARGs and ARB in different types of STPs. | 2020 | 32092547 |
| 6380 | 1 | 0.9869 | Seasonal dynamics of anammox bacteria in estuarial sediment of the Mai Po Nature Reserve revealed by analyzing the 16S rRNA and hydrazine oxidoreductase (hzo) genes. The community and population dynamics of anammox bacteria in summer (wet) and winter (dry) seasons in estuarial mudflat sediment of the Mai Po Nature Reserve were investigated by 16S rRNA and hydrazine oxidoreductase (hzo) genes. 16S rRNA phylogenetic diversity showed that sequences related to 'Kuenenia' anammox bacteria were presented in summer but not winter while 'Scalindua' anammox bacteria occurred in both seasons and could be divided into six different clusters. Compared to the 16S rRNA genes, the hzo genes revealed a relatively uniform seasonal diversity, with sequences relating to 'Scalindua', 'Anammoxoglobus', and planctomycete KSU-1 found in both seasons. The seasonal specific bacterial groups and diversity based on the 16S rRNA and hzo genes indicated strong seasonal community structures in estuary sediment of this site. Furthermore, the higher abundance of hzo genes in summer than winter indicates clear seasonal population dynamics. Combining the physicochemical characteristics of estuary sediment in the two seasons and their correlations with anammox bacteria community structure, we proposed the strong seasonal dynamics in estuary sediment of Mai Po to be due to the anthropogenic and terrestrial inputs, especially in summer, which brings in freshwater anammox bacteria, such as 'Kuenenia', interacting with the coastal marine anammox bacteria 'Scalindua'. | 2011 | 21487198 |
| 7054 | 2 | 0.9867 | Effective removal of antibiotic resistance genes and potential links with archaeal communities during vacuum-type composting and positive-pressure composting. As a major reservoir of antibiotics, animal manure contributes a lot to the augmented environmental pressure of antibiotic resistance genes (ARGs). This might be the first study to explore the effects of different ventilation types on the control of ARGs and to identify the relationships between archaeal communities and ARGs during the composting of dairy manure. Several ARGs were quantified via Real-time qPCR and microbial communities including bacteria and archaea were analyzed by High-throughput sequencing during vacuum-type composting (VTC) and positive-pressure composting (PPC). The total detected ARGs and class I integrase gene (intI1) under VTC were significantly lower than that under PPC during each stage of the composting (p<0.001). The relative abundance of potential human pathogenic bacteria (HPB) which were identified based on sequencing information and correlation analysis decreased by 74.6% and 91.4% at the end of PPC and VTC, respectively. The composition of archaeal communities indicated that methane-producing archaea including Methanobrevibacter, Methanocorpusculum and Methanosphaera were dominant throughout the composting. Redundancy analysis suggested that Methanobrevibacter and Methanocorpusculum were positively correlated with all of the detected ARGs. Network analysis determined that the possible hosts of ARGs were different under VTC and PPC, and provided new sights about potential links between archaea and ARGs. Our results showed better performance of VTC in reducing ARGs and potential HPB and demonstrated that some archaea could also be influential hosts of ARGs, and caution the risks of archaea carrying ARGs. | 2020 | 31892399 |
| 7133 | 3 | 0.9865 | Prevalence of antibiotic resistance genes in bacterial communities associated with Cladophora glomerata mats along the nearshore of Lake Ontario. The alga Cladophora glomerata can erupt in nuisance blooms throughout the lower Great Lakes. Since bacterial abundance increases with the emergence and decay of Cladophora, we investigated the prevalence of antibiotic resistance (ABR) in Cladophora-associated bacterial communities up-gradient and down-gradient from a large sewage treatment plant (STP) on Lake Ontario. Although STPs are well-known sources of ABR, we also expected detectable ABR from up-gradient wetland communities, since they receive surface run-off from urban and agricultural sources. Statistically significant differences in aquatic bacterial abundance and ABR were found between down-gradient beach samples and up-gradient coastal wetland samples (ANOVA, Holm-Sidak test, p < 0.05). Decaying and free-floating Cladophora sampled near the STP had the highest bacterial densities overall, including on ampicillin- and vancomycin-treated plates. However, quantitative polymerase chain reaction analysis of the ABR genes ampC, tetA, tetB, and vanA from environmental communities showed a different pattern. Some of the highest ABR gene levels occurred at the 2 coastal wetland sites (vanA). Overall, bacterial ABR profiles from environmental samples were distinguishable between living and decaying Cladophora, inferring that Cladophora may control bacterial ABR depending on its life-cycle stage. Our results also show how spatially and temporally dynamic ABR is in nearshore aquatic bacteria, which warrants further research. | 2017 | 28192677 |
| 6991 | 4 | 0.9863 | Distribution and drivers of antibiotic resistance genes in brackish water aquaculture sediment. Brackish water aquaculture has brought numerous economic benefits, whereas anthropogenic activities in aquaculture may cause the dissemination of antibiotic resistance genes (ARGs) in brackish water sediments. The intricate relationships between environmental factors and microbial communities as well as their role in ARGs dissemination in brackish water aquaculture remain unclear. This study applied PCR and 16S sequencing to identify the variations in ARGs, class 1 integron gene (intI1) and microbial communities in brackish water aquaculture sediment. The distribution of ARGs in brackish water aquaculture sediment was similar to that in freshwater aquaculture, and the sulfonamide resistance gene sul1 was the indicator of ARGs. Proteobacteria and Firmicutes were the dominant phyla, and Paenisporosarcina (p_ Firmicutes) was the dominant genus. The results of correlation, network and redundancy analysis indicated that the microbial community in the brackish water aquaculture sediment was function-driven. The neutral model and variation partitioning analysis were used to verify the ecological processes of the bacterial community. The normalized stochasticity ratio showed that pond bacteria community was dominated by determinacy, which was affected by aquaculture activities. The total nitrogen and organic matter influenced the abundance of ARGs, while Proteobacteria and Thiobacillus (p_Proteobacteria) were the key antibiotic-resistant hosts. Our study provides insight into the prevalence of ARGs in brackish water aquaculture sediments, and indicates that brackish water aquaculture is a reservoir of ARGs. | 2023 | 36436623 |
| 7139 | 5 | 0.9863 | Variations in antibiotic resistance genes and microbial community in sludges passing through biological nutrient removal and anaerobic digestion processes in municipal wastewater treatment plants. Antimicrobial resistance (AMR) represents a relentless, silent pandemic. Contributing to this are wastewater treatment plants (WWTPs), a potential source of antibiotic resistance genes' (ARGs) transmission to the environment, threatening public health. The presence of ARGs in pathogenic bacteria and their release into the environment by WWTPs threatens the public health. The current study investigated changes in ARGs' abundance in biological nutrient removal (BNR) processes and anaerobic digestion (AD) reactors of two WWTPs. Also, microbial community structure, which is known to shape the distribution and abundance of ARGs, was also analyzed. The relative abundance of eight ARGs (tetX, tetA, tetM, TEM, sul1, sul2, ermB and qnrD) was quantified as ARGs' copies/16 S rRNA gene copies using quantitative polymerase chain reaction (qPCR). Microbial community composition was assessed by 16 S rRNA microbiome sequencing analysis. TetX was prevalent among the eight ARGs, followed by TEM and sul1. However, its abundance was decreased in the AD sludges compared to BNR sludges. Proteobacteria was the major bacterial phylum found in all the sludge samples, while Arcobacter, 12up and Acidovorax were the predominant genera. Acinetobacter and Flavobacterium were significantly more abundant in the BNR sludges, while 12up and Aeromonas were predominant in AD sludges. Principal component analysis (PCA) revealed a clear difference in dominant ARGs and bacteria between the sludges in the processes of BNR and AD of the two WWTPs. Clinically relevant bacterial genera, Klebsiella and Enterococcus, found in both the BNR and AD sludges, were significantly correlated with the tetX gene. Throughout this study, the relationship between microbial communities and specific ARGs was revealed, illustrating that the composition of the microbial community could play a vital role in the abundance of ARGs. These results will better inform future studies aimed at controlling the spread of ARGs and their potential hosts from WWTPs. | 2023 | 36427585 |
| 6389 | 6 | 0.9861 | Microbial community and functions involved in smokeless tobacco product: a metagenomic approach. Smokeless tobacco products (STPs) are attributed to oral cancer and oral pathologies in their users. STP-associated cancer induction is driven by carcinogenic compounds including tobacco-specific nitrosamines (TSNAs). The TSNAs synthesis could enhanced due to the metabolic activity (nitrate metabolism) of the microbial populations residing in STPs, but identifying microbial functions linked to the TSNAs synthesis remains unexplored. Here, we rendered the first report of shotgun metagenomic sequencing to comprehensively determine the genes of all microorganisms residing in the Indian STPs belonging to two commercial (Moist-snuff and Qiwam) and three loose (Mainpuri Kapoori, Dohra, and Gudakhu) STPs, specifically consumed in India. Further, the level of nicotine, TSNAs, mycotoxins, and toxic metals were determined to relate their presence with microbial activity. The microbial population majorly belongs to bacteria with three dominant phyla including Actinobacteria, Proteobacteria, and Firmicutes. Furthermore, the STP-linked microbiome displayed several functional genes associated with nitrogen metabolism and antibiotic resistance. The chemical analysis revealed that the Mainpuri Kapoori product contained a high concentration of ochratoxins-A whereas TSNAs and Zink (Zn) quantities were high in the Moist-snuff, Mainpuri Kapoori, and Gudakhu products. Hence, our observations will help in attributing the functional potential of STP-associated microbiome and in the implementation of cessation strategies against STPs. KEY POINTS: •Smokeless tobacco contains microbes that can assist TSNA synthesis. •Antibiotic resistance genes present in smokeless tobacco-associated bacteria. •Pathogens in STPs can cause infections in smokeless tobacco users. | 2024 | 38918238 |
| 7167 | 7 | 0.9860 | Occurrence 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. | 2024 | 38782270 |
| 6824 | 8 | 0.9859 | Anthropogenic gene dissemination in Tibetan Plateau rivers: sewage-driven spread, environmental selection, and microeukaryotic inter-trophic driving factors. The spread of anthropogenic genes, such as antibiotic resistance genes (ARGs), mobile genetic elements (MGEs), virulence factor genes (VFGs), and antibiotic-resistant bacteria (ARBs), is a growing public health concern. However, the role of anthropogenic activities in the dissemination of these genes and bacteria in Tibetan Plateau rivers is still unclear. In this study, we analyzed 138 metagenomic samples from water and sediment across nine Tibetan rivers, along with sewage samples from 21 wastewater treatment plants (WWTPs), at both the gene and contig levels, to investigate the spread of the sewage-enriched genes and their bacterial hosts (contigs) in Tibetan rivers. Overall, sewage input was positively correlated with increased the abundance of an average 56 % and 17 % of detected genes in water and sediment, respectively. However, FEAST source tracking analysis revealed that the overall contribution of sewage across all rivers was significantly lower than that of water and sediment. Additionally, sewage's impact varied across rivers, with the Yarlung Zangbo, the largest river, exhibiting limited influence despite receiving inputs from smaller rivers and WWTPs. Neutral community model (NCM) suggested that neutral processes and negative selection predominantly governed the spread of majority of highly abundant sewage-enriched genes and contigs, suggesting restricted environmental spread. In contrast, a subset of genes over-represented relative to neutral expectations (above-neutral prediction) showed lower overall abundance but higher richness, potentially reflecting selection that favor their retention in certain downstream environments. Furthermore, sewage-enriched genes and contigs in water, regardless of their community assembly processes, were linked to microbial interaction modules dominated by microeukaryotic groups associated with sewage, including consumer protists (ciliate), human parasites (e.g., Naegleria), algae, and fungi. These interactions may facilitate the dissemination of antimicrobial resistance in aquatic environments, though this pattern was less pronounced in sediment. | 2025 | 40446767 |
| 7215 | 9 | 0.9859 | High-throughput qPCR profiling of antimicrobial resistance genes and bacterial loads in wastewater and receiving environments. Wastewater treatment plants (WWTPs) are hot spots for the acquisition and spread of antimicrobial resistance (AMR). This regional-based study quantified antibiotic resistance genes (ARGs), mobile genetic elements (MGEs), and bacteria in hospital and community-derived wastewater and receiving environments, using high-throughput qPCR (HT-qPCR). This is the first study to apply Resistomap's Antibiotic Resistance Gene Index (ARGI) as a standardised metric to find the overall AMR level across different WWTPs. ARGI of WWTPs ranged from 2.0 to 2.3, indicating higher relative ARG levels than the mean European ARGI of 2.0, but lower than the global mean of 2.4. The highest diversity and abundance of ARGs were observed in untreated hospital and community wastewater. The reduction of total ARGs during wastewater treatment (0.2-2 logs) and bacteria (0.3-1.5 logs) varied spatio-temporally across the WWTPs. Despite a decrease in ARG and bacterial abundance in treated effluents, substantial loads were still released into receiving environments. Notably, ARG levels in coastal sediments were comparable to those in untreated wastewater, and most ARGs were shared between wastewater and receiving environments, highlighting the impact of wastewater discharge on these ecosystems. Sewage outfall exposure increased ARGs in shellfish, emphasising risks to shellfish hygiene. This study provides evidence to inform policymaking, emphasising advanced wastewater treatment methods and combined sewer overflow (CSO) management to mitigate ARG release, protecting water users and the food chain. | 2025 | 40127809 |
| 6921 | 10 | 0.9859 | Impacts of Chemical and Organic Fertilizers on the Bacterial Communities, Sulfonamides and Sulfonamide Resistance Genes in Paddy Soil Under Rice-Wheat Rotation. The responses of sulfonamides, sulfonamide-resistance genes (sul) and soil bacterial communities to different fertilization regimes were investigated by performing a field experiment using paddy soil with no fertilizer applied, chemical fertilizer applied, organic fertilizer applied, and combination of chemical and organic fertilizer applied. Applying organic fertilizer increased the bacterial community diversity and affected the bacterial community composition. Eutrophic bacteria (Bacteroidetes, Gemmatimonadetes, and Proteobacteria) were significantly enriched by applying organic fertilizer. It was also found organic fertilizer application increased sulfamethazine content and the relative abundances of sul1 and sul2 in the soil. In contrast, applying chemical fertilizer significantly increased the abundance of Nitrospirae, Parcubacteria, and Verrucomicrobia and caused no obvious changes on sul. Correlation analysis indicated that sul enrichment was associated with the increases in sulfamethazine content and potential hosts (e.g., Novosphingobium and Rhodoplanes) population. The potential ecological risks of antibiotics in paddy soil with organic fertilizer applied cannot be ignored. | 2022 | 36547725 |
| 7950 | 11 | 0.9859 | Fate and removal of fluoroquinolone antibiotics in mesocosmic wetlands: Impact on wetland performance, resistance genes and microbial communities. The fate of fluoroquinolone antibiotics norfloxacin and ofloxacin were investigated in mesocosmic wetlands, along with their effects on nutrients removal, antibiotic resistance genes (ARGs) and epiphytic microbial communities on Hydrilla verticillate using bionic plants as control groups. Approximately 99% of norfloxacin and ofloxacin were removed from overlaying water, and H. verticillate inhibited fluoroquinolones accumulation in surface sediments compared to bionic plants. Partial least squares path modeling showed that antibiotics significantly inhibited the nutrient removal capacity (0.55) but had no direct effect on plant physiology. Ofloxacin impaired wetland performance more strongly than norfloxacin and more impacted the primary microbial phyla, whereas substrates played the most decisive role on microbial diversities. High antibiotics concentration shifted the most dominant phyla from Proteobacteria to Bacteroidetes and inhibited the Xenobiotics biodegradation function, contributing to the aggravation in wetland performance. Dechloromonas and Pseudomonas were regarded as the key microorganisms for antibiotics degradation. Co-occurrence network analysis excavated that microorganisms degrade antibiotics mainly through co-metabolism, and more complexity and facilitation/reciprocity between microbes attached to submerged plants compared to bionic plants. Furthermore, environmental factors influenced ARGs mainly by altering the community dynamics of differential bacteria. This study offers new insights into antibiotic removal and regulation of ARGs accumulation in wetlands with submerged macrophyte. | 2024 | 38569335 |
| 7949 | 12 | 0.9859 | Tetracycline and quinolone contamination mediate microbial and antibiotic resistant gene composition in epiphytic biofilms of mesocosmic wetlands. The fate and ecological impact of antibiotics on aquatic ecosystems have not been properly elucidated in mesocosm wetlands scale. This study explored how tetracyclines (TCs, including tetracycline TC and oxytetracycline) and fluoroquinolones (QNs, including ciprofloxacin CIP and levofloxacin) affect mesocosm wetlands vegetated by V. spiralis, focusing on their impact on epiphytic biofilm microbial communities and antibiotic resistance genes (ARGs). Results showed that submerged plants absorbed more antibiotics than sediment. Both TCs and QNs disrupted microbial communities in different ways and increased eukaryotic community diversity in a concentration-dependent manner (2-4 mg/L for CIP, 4-8 mg/L for TC). TCs mainly inhibited epiphytic bacteria, while CIP increased bacterial phyla abundance. TC reduced Cyanobacteriota, Acidobacteriota, and Patescibacteria but increased Bacillota, Bacteroidota, and Armatimonadota. In contrast, CIP reduced Bacteroidota, Cyanobacteriota, and Gemmatimonadota but increased Bacillota, Planctomycetota, and Acidobacteriota. Significant differences in ARG profiles were observed between QNs and TCs, with TCs having a more substantial effect on ARGs due to their stronger impact on bacterial communities. Both antibiotics raised ARG levels with higher concentrations, particularly for multidrug resistance, tetracyclines, trimethoprim, sulfonamides, aminoglycosides, and fosfomycin, emphasizing their role in antimicrobial resistance. The study suggests that antibiotics can either stimulate or inhibit ARGs depending on their effects on bacterial communities. This study provides key evidence on the ecological mechanisms underlying the impact of TCs and QNs on epiphytic microbes of mesocosm wetlands. | 2024 | 39321725 |
| 7166 | 13 | 0.9859 | Foam shares antibiotic resistomes and bacterial pathogens with activated sludge in wastewater treatment plants. Foaming is a common operational problem that occurs in activated sludge (AS) from many wastewater treatment plants (WWTPs), but the characteristic of antibiotic resistance genes (ARGs) and human pathogenic bacteria (HPB) in foams is generally lacking. Here, we used a metagenomic approach to characterize the profile of ARGs and HPB in foams and AS from full-scale WWTPs receiving pesticide wastewater. No significant difference in the microbial communities was noted between the AS and foam samples. The diversity and abundance of ARGs in the foams were similar to those in the pertinent AS samples. Procrustes analysis suggested that the bacterial community is the major driver of ARGs. Metagenomic assembly also indicated that most ARGs (e.g., multidrug, rifamycin, peptides, macrolide-lincosamide-streptogramin, tetracycline, fluoroquinolone, and beta-lactam resistance genes) were carried by chromosomes rather than mobile genetic elements. Moreover, the relative abundances of HPB, Pseudomonas putida and Mycobacterium smegmatis, were enriched in the foam samples. Nine HPB were identified as carriers of 21 ARG subtypes, of which Pseudomonas aeruginosa could carry 12 ARG subtypes. Overall, this study indicates the prevalence of ARGs, HPB, and ARG-carrying HPB in foams, which highlights the potential risk of foams in spreading ARGs and HPB into the surrounding environments. | 2021 | 33373956 |
| 8581 | 14 | 0.9859 | Tire particles and its leachates: Impact on antibiotic resistance genes in coastal sediments. Tire particles (TPs), a significant group of microplastics, can be discharged into the coastal environments in various ways. However, our understanding of how TPs impact the antibiotic resistance and pathogenic risks of microorganisms in coastal sediments remains limited. In this study, we used metagenomics to investigate how TPs and their leachates could affect the prevalence of antibiotic resistance genes (ARGs), virulence factor genes (VFGs), and their potential risks to the living creatures such as soil invertebrates and microorganisms in the coastal sediments. We discovered that TP addition significantly increased the abundance and diversity of ARGs and VFGs in coastal sediments, with raw TPs displayed higher impacts than TP leachates and TPs after leaching on ARGs and VFGs. With increasing TP exposure concentrations, the co-occurrence frequency of ARGs and mobile genetic elements (MGEs) in the same contig also increased, suggesting that TPs could enhance the dispersal risk of ARGs. Our metagenome-based binning analysis further revealed that exposure to TPs increased the abundance of potentially pathogenic antibiotic-resistant bacteria (PARB). In addition, chemical additives of TP leachates (e.g., Zn and N-cyclohexylformamide) significantly affected the changes of ARGs in the pore water. In summary, our study provides novel insights into the adverse effects of TP pollutions on aggravating the dissemination and pathogenic risks of ARGs and PARB in the coastal environment. | 2024 | 38147751 |
| 6995 | 15 | 0.9859 | Insight into the spatiotemporal distribution of antibiotic resistance genes in estuarine sediments during long-term ecological restoration. In this study, we aimed to investigate the long-term spatiotemporal changes in hydrodynamics, antibiotics, nine typical subtypes of antibiotic resistance genes (ARGs), class 1 integron gene (intI1), and microbial communities in the sediments of a semi-enclosed estuary during ecological restoration with four treatment stages (influent (#1), effluent of the biological treatment area (#2), oxic area (#3), and plant treatment area (#4)). Ecological restoration of the estuary reduced common pollutants (nitrogen and phosphorus) in the water, whereas variations in ARGs showed noticeable seasonal and spatial features. The absolute abundance of ARGs at sampling site #2 considerably increased in autumn and winter, while it significantly increased at sampling site #3 in spring and summer. The strong intervention of biological treatment (from #1 to #2) and aerators (from #2 to #3) in the estuary substantially affected the distribution of ARGs and dominant antibiotic-resistant bacteria (ARB). The dominant ARB (Thiobacillus) in estuarine sediments may have low abundance but important dissemination roles. Meanwhile, redundancy and network analysis revealed that the microbial communities and intl1 were key factors related to ARG dissemination, which was affected by spatial and seasonal ecological restoration. A positive correlation between low flow velocity and certain ARGs (tetM, tetW, tetA, sul2, and ermC) was observed, implying that flow optimization should also be considered in future ecological restoration to remediate ARGs. Furthermore, the absolute abundance of ARGs can be utilized as an index to evaluate the removal capacity of ARGs by estuarine restoration. | 2023 | 36827800 |
| 7008 | 16 | 0.9859 | Pharmaceutical exposure changed antibiotic resistance genes and bacterial communities in soil-surface- and overhead-irrigated greenhouse lettuce. New classes of emerging contaminants such as pharmaceuticals, antibiotic resistant bacteria (ARB), and antibiotic resistance genes (ARGs) have received increasing attention due to rapid increases of their abundance in agroecosystems. As food consumption is a direct exposure pathway of pharmaceuticals, ARB, and ARGs to humans, it is important to understand changes of bacterial communities and ARG profiles in food crops produced with contaminated soils and waters. This study examined the level and type of ARGs and bacterial community composition in soil, and lettuce shoots and roots under soil-surface or overhead irrigation with pharmaceuticals-contaminated water, using high throughput qPCR and 16S rRNA amplicon sequencing techniques, respectively. In total 52 ARG subtypes were detected in the soil, lettuce shoot and root samples, with mobile genetic elements (MGEs), and macrolide-lincosamide-streptogramin B (MLSB) and multidrug resistance (MDR) genes as dominant types. The overall abundance and diversity of ARGs and bacteria associated with lettuce shoots under soil-surface irrigation were lower than those under overhead irrigation, indicating soil-surface irrigation may have lower risks of producing food crops with high abundance of ARGs. ARG profiles and bacterial communities were sensitive to pharmaceutical exposure, but no consistent patterns of changes were observed. MGE intl1 was consistently more abundant with pharmaceutical exposure than in the absence of pharmaceuticals. Pharmaceutical exposure enriched Proteobacteria (specifically Methylophilaceae) and decreased bacterial alpha diversity. Finally, there were significant interplays among bacteria community, antibiotic concentrations, and ARG abundance possibly involving hotspots including Sphingomonadaceae, Pirellulaceae, and Chitinophagaceae, MGEs (intl1 and tnpA_1) and MDR genes (mexF and oprJ). | 2019 | 31336252 |
| 6917 | 17 | 0.9858 | Response characteristics of antibiotic resistance genes and bacterial communities during agricultural waste composting: Focusing on biogas residue combined with biochar amendments. This research investigated biogas residue and biochar addition on antibiotic resistance genes (ARGs), mobile genetic elements (MGEs), and changes in bacterial community during agricultural waste composting. Sequencing technique investigated bacterial community structure and ARGs, MGEs changes. Correlations among physicochemical factors, ARGs, MGEs, and bacterial community structure were determined using redundancy analysis. Results confirmed that biochar and biogas residue amendments effectively lowered the contents of ARGs and MGEs. The main ARGs detected was sul1. Proteobacteria and Firmicutes were the main host bacteria strongly associated with the dissemination of ARGs. The dynamic characteristics of the bacterial community were strongly correlated with pile temperature and pH (P < 0.05). Redundancy and network analysis revealed that nitrate, intI1, and Firmicutes mainly affected the in ARGs changes. Therefore, regulating these key variables would effectively suppress the ARGs spread and risk of compost use. | 2023 | 36657587 |
| 7014 | 18 | 0.9858 | Correlations among Antibiotic Resistance Genes, Mobile Genetic Elements and Microbial Communities in Municipal Sewage Treatment Plants Revealed by High-Throughput Sequencing. Municipal sewage treatment plants (MSTPs) are environmental pools for antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs), which is cause for growing environmental-health concerns. In this study, the effects of different wastewater treatment processes on microbial antibiotic resistance in four MSTPs were investigated. PCR, q-PCR, and molecular cloning integrally indicated that the tetracycline resistance (tet) genes significantly reduced after activated-sludge treatment. Illumina high-throughput sequencing revealed that the broad-spectrum profile of ARGs and mobile element genes (MGEs) were also greatly decreased by one order of magnitude via activated sludge treatment and were closely associated with each other. Correlations between ARGs and bacterial communities showed that potential ARB, such as Acinetobacter, Bacteroides, and Cloaibacterium, were removed by the activated-sludge process. Sedimentation processes cannot significantly affect the bacterial structure, resulting in the relative abundance of ARGs, MGEs, and ARB in second-clarifier effluent water being similar to activated sludge. A comprehensive study of ARGs associated with MGEs and bacterial structure might be technologically guided for activated sludge design and operation in the MSTPs, to purposefully control ARGs carried by pathogenic hosts and mobility. | 2023 | 36834289 |
| 7742 | 19 | 0.9858 | The dissimilarity of antibiotic and quorum sensing inhibitor on activated sludge nitrification system: Microbial communities and antibiotic resistance genes. Effects of antibiotics (azithromycin, AZM, 1-40 mg/L) and quorum sensing inhibitor (QSI, 2(5H)-furanone, 1-40 mg/L) combined pollution with environmental concentration of copper on bacterial/archaeal community and antibiotic resistance genes (ARGs) in activated sludge system were explored. QSI inhibited nitrification more obviously than AZM. AZM and QSI were synergistic inhibitions on bacterial diversity, and AZM inhibited bacterial compositions more than QSI. While, QSI had more impacts on archaeal diversity/compositions. Less interactions among bacteria and archaea communities with Aquimonas as keystone genus. Functional differences in bacteria/archaea communities were little, and AZM had more effects on metabolism. AZM mainly affected nitrifying bacteria (Candidatus Nitrospira nitrificans and Nitrosomonas). Specific denitrifying bacteria were enriched by AZM (Brevundimonas, 1.76-31.69%) and QSI (Comamonas, 0.61-9.61%), respectively. AZM enriched ARGs more easily than QSI and they were antagonistic to proliferation of ARGs. Bacteria were main hosts of ARGs (macrolide-lincosamide-streptogramin B, other/efflux, etc.) and archaea (Methanosphaerula, Methanolobus) carried multiple ARGs. | 2022 | 35306131 |