Supercarriers of antibiotic resistome in a world's large river. - Related Documents




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679701.0000Supercarriers of antibiotic resistome in a world's large river. BACKGROUND: Antibiotic resistome has been found to strongly interact with the core microbiota in the human gut, yet little is known about how antibiotic resistance genes (ARGs) correlate with certain microbes in large rivers that are regarded as "terrestrial gut." RESULTS: By creating the integral pattern for ARGs and antibiotic-resistant microbes in water and sediment along a 4300-km continuum of the Yangtze River, we found that human pathogen bacteria (HPB) share 13.4% and 5.9% of the ARG hosts in water and sediment but contribute 64% and 46% to the total number of planktonic and sedimentary ARGs, respectively. Moreover, the planktonic HPB harbored 79 ARG combinations that are dominated by "natural" supercarriers (e.g., Rheinheimera texasensis and Noviherbaspirillum sp. Root189) in river basins. CONCLUSIONS: We confirmed that terrestrial HPB are the major ARG hosts in the river, rather than conventional supercarriers (e.g., Enterococcus spp. and other fecal indicator bacteria) that prevail in the human gut. The discovery of HPB as natural supercarriers in a world's large river not only interprets the inconsistency between the spatial dissimilarities in ARGs and their hosts, but also highlights the top priority of controlling terrestrial HPB in the future ARG-related risk management of riverine ecosystems globally. Video Abstract.202235897057
682510.9997Bacteria and Antibiotic Resistance Genes (ARGs) in PM(2.5) from China: Implications for Human Exposure. Airborne transmission is one of the environmental dissemination pathways of antibiotic resistance genes (ARGs), and has critical implications for human exposure through inhalation. In this study, we focused on three regions of China to reveal some unique spatiotemporal features of airborne bacteria and ARGs in fine aerosols (PM(2.5)): (1) greater seasonal variations in the abundance of bacteria and ARGs in temperate urban Beijing than in the subtropical urban areas of the Yangtze River Delta (YRD) and Pearl River Delta (PRD) regions, with regional disparities in bacterial communities; (2) geographical fingerprints of ARG profiles independent of seasonal cycles and land-use gradients within each region; (3) region-independent associations between the targeted ARGs and limited bacterial genera; (4) common correlations between ARGs and mobile genetic elements (MGEs) across regions; and (5) PM(2.5) at the higher end of ARG enrichment across various environmental and human media. The spatiotemporally differentiated bacterial communities and ARG abundances, and the compositions, mobility, and potential hosts of ARGs in the atmosphere have strong implications for human inhalational exposure over spatiotemporal scales. By comparing other contributing pathways for the intake of ARGs (e.g., drinking water and food ingestion) in China and the U.S.A., we identified the region-specific importance of inhalation in China as well as country-specific exposure scenarios. Our study thus highlights the significance of inhalation as an integral part of the aggregate exposure pathways of environmentally disseminated ARGs, which, in turn, may help in the formulation of adaptive strategies to mitigate the exposure risks in China and beyond.201930525504
317220.9997Metagenomic and Culturomics Analysis of Microbial Communities within Surface Sediments and the Prevalence of Antibiotic Resistance Genes in a Pristine River: The Zaqu River in the Lancang River Source Region, China. Microbial communities inhabiting sedimentary environments in river source regions serve as pivotal indicators of pristine river ecosystems. While the correlation between antibiotic resistome and pathogenicity with core gut bacteria in humans is well established, there exists a significant knowledge gap concerning the interaction of antibiotic resistance genes (ARGs) and human pathogenic bacteria (HPB) with specific microbes in river source basins, often referred to as "terrestrial gut". Understanding the microbial composition, including bacteria and resident genetic elements such as ARGs, HPB, Mobile Genetic Elements (MGEs), and Virulence Factors (VFs), within natural habitats against the backdrop of global change, is imperative. To address this gap, an enrichment-based culturomics complementary along with metagenomics was conducted in this study to characterize the microbial biobank and provide preliminary ecological insights into profiling the dissemination of ARGs in the Lancang River Source Basin. Based on our findings, in the main stream of the Lancang River Source Basin, 674 strains of bacteria, comprising 540 strains under anaerobic conditions and 124 under aerobic conditions, were successfully isolated. Among these, 98 species were identified as known species, while 4 were potential novel species. Of these 98 species, 30 were HPB relevant to human health. Additionally, bacA and bacitracin emerged as the most abundant ARGs and antibiotics in this river, respectively. Furthermore, the risk assessment of ARGs predominantly indicated the lowest risk rank (Rank Ⅳ) in terms of endangering human health. In summary, enrichment-based culturomics proved effective in isolating rare and unknown bacteria, particularly under anaerobic conditions. The emergence of ARGs showed limited correlation with MGEs, indicating minimal threats to human health within the main stream of the Lancang River Source Basin.202438792738
717330.9997Animal farms are hot spots for airborne antimicrobial resistance. Animal farms are known reservoirs for environmental antimicrobial resistance (AMR). However, knowledge of AMR burden in the air around animal farms remains disproportionately limited. In this study, we characterized the airborne AMR based on the quantitative information of 30 antimicrobial resistance genes (ARGs), four mobile genetic elements (MGEs), and four human pathogenic bacteria (HPBs) involving four animal species from 20 farms. By comparing these genes with those in animal feces, the distinguishing features of airborne AMR were revealed, which included high enrichment of ARGs and their potential mobility to host HPBs. We found that depending on the antimicrobial class, the mean concentration of airborne ARGs in the animal farms ranged from 10(2) to 10(4) copies/m(3) and was accompanied by a considerable intensity of MGEs and HPBs (approximately 10(3) copies/m(3)). Although significant correlations were observed between the ARGs and bacterial communities of air and fecal samples, the abundance of target genes was generally high in fine inhalable particles (PM2.5), with an enrichment ratio of up to 10(2) in swine and cattle farms. The potential transferability of airborne ARGs was universally strengthened, embodied by a pronounced co-occurrence of ARGs-MGEs in air compared with that in feces. Exposure analysis showed that animal farmworkers may inhale approximately 10(4) copies of human pathogenic bacteria-associated genera per day potentially carrying highly transferable ARGs, including multidrug resistant Staphylococcus aureus. Moreover, PM2.5 inhalation posed higher human daily intake burdens of some ARGs than those associated with drinking water intake. Overall, our findings highlight the severity of animal-related airborne AMR and the subsequent inhalation exposure, thus improving our understanding of the airborne flow of AMR genes from animals to humans. These findings could help develop strategies to mitigate the human exposure and dissemination of ARGs across different media.202235985594
317140.9997Health risk ranking of antibiotic resistance genes in the Yangtze River. Antibiotic resistance is an escalating global health concern, exacerbated by the pervasive presence of antibiotic resistance genes (ARGs) in natural environments. The Yangtze River, the world's third-longest river, traversing areas with intense human activities, presents a unique ecosystem for studying the impact of these genes on human health. Here, we explored ARGs in the Yangtze River, examining 204 samples from six distinct habitats of approximately 6000 km of the river, including free-living and particle-associated settings, surface and bottom sediments, and surface and bottom bank soils. Employing shotgun sequencing, we generated an average of 13.69 Gb reads per sample. Our findings revealed a significantly higher abundance and diversity of ARGs in water-borne bacteria compared to other habitats. A notable pattern of resistome coalescence was observed within similar habitat types. In addition, we developed a framework for ranking the risk of ARG and a corresponding method for calculating the risk index. Applying them, we identified water-borne bacteria as the highest contributors to health risks, and noted an increase in ARG risks in particle-associated bacteria correlating with heightened anthropogenic activities. Further analysis using a weighted ARG risk index pinpointed the Chengdu-Chongqing and Yangtze River Delta urban agglomerations as regions of elevated health risk. These insights provide a critical new perspective on ARG health risk assessment, highlighting the urgent need for strategies to mitigate the impact of ARGs on human health and to preserve the ecological and economic sustainability of the Yangtze River for future human use.202438351955
681850.9996Atmospheric antibiotic resistome driven by air pollutants. The atmosphere is an important reservoir and habitat for antibiotic resistance genes (ARGs) and is a main pathway to cause potential health risks through inhalation and ingestion. However, the distribution characteristics of ARGs in the atmosphere and whether they were driven by atmospheric pollutants remain unclear. We annotated 392 public air metagenomic data worldwide and identified 1863 ARGs, mainly conferring to tetracycline, MLS, and multidrug resistance. We quantified these ARG's risk to human health and identified their principal pathogenic hosts, Burkholderia and Staphylococcus. Additionally, we found that bacteria in particulate contaminated air carry more ARGs than in chemically polluted air. This study revealed the influence of typical pollutants in the global atmosphere on the dissemination and risk of ARGs, providing a theoretical basis for the prevention and mitigation of the global risks associated with ARGs.202337543315
317660.9996Comprehensive profiling and risk assessment of antibiotic resistance genes in a drinking water watershed by integrated analysis of air-water-soil. The prevalence of antibiotic resistance genes (ARGs) in diverse habitats threatens public health. Watersheds represent critical freshwater ecosystems that interact with both the soil and atmosphere. However, a holistic understanding of ARGs distribution across these environmental media is currently inadequate. We profiled ARGs and bacterial communities in air-water-soil in the same watershed area during four seasons using high-throughput qPCR and 16S rRNA gene sequencing. Our findings demonstrated that aminoglycoside resistance genes (58.5%) were dominant in water, and multidrug resistance genes (55.2% and 54.2%) were dominant in soil and air. Five ARGs and nineteen bacterial genera were consistently detected in all samples, were named as shared genes or bacteria. Co-occurrence Network analysis revealed the co-occurrence module of resistance genes, mobile genetic elements (MGEs), and potential bacterial hosts, indicating that shared genes and bacteria may persist and co-spread across different environmental media. The risk assessment framework, based on ARGs' abundance, detection rate, and mobility, identified 33 high-risk ARGs. This is essential to evaluate the health risks of ARGs and to develop strategies to limit the threat of antibiotic resistance. Our study offers new insights into the risks associated with ARGs in the environment and suggests that ARGs may depend on specific bacterial cohabitants that co-exist with MGEs to facilitate their spread across environmental interfaces.202337742410
688670.9996Bacterial community and antibiotic resistance genes assembly processes were shaped by different mechanisms in the deep-sea basins of the Western Pacific Ocean. As the intrinsic property of microorganisms, antibiotic resistance genes (ARGs) are fundamentally coupled to microbially-linked biogeochemical processes within ecosystems. However, human activities often obscure the natural distribution of ARGs through deterministic selective pressures. The deep-sea basin of the western Pacific Ocean is one of the least disturbed areas globally by human activities, providing a natural laboratory to investigate the intrinsic mechanisms governing ARGs in natural environments. In this study, we analyzed bacterial community and ARG diversity in 15 surface sediment samples from three deep-sea basins in the western Pacific Ocean. The relative abundance of ARGs in the surface sediments ranged from 3.10 × 10(-3) to 5.37 × 10(-2) copies/16S rRNA copies, with multidrug and β-lactam resistance genes dominated in all samples (49.06%-100%). The bacteria were mainly dominated by the Proteobacteria. The principal coordinate analysis (PCoA) showed significant spatial heterogeneity of ARGs and bacteria among the three basins. Null model, neutral community models (NCM), and normalized stochasticity ratio (NST) indicated that bacterial community was dominated by stochastic assembly, driven by geographic barriers leading to independent evolution. Conversely, the NST revealed that the ARGs profile was mainly shaped by deterministic processes. Environmental factors are more crucial than geographical factors and bacterial community for ARG occurrence among the selected factors. Meanwhile, we found that the spread of ARGs was mainly through vertical gene transfer in the pre-antibiotic era. The disparity between the assembly processes of bacterial community and ARGs may be attributed to the fact that ARG hosts were not the dominant bacteria in the community. This study first reported the distribution and assembly processes of ARGs and bacterial community in surface sediments of the western Pacific.202439481517
683880.9996Seasonal variation characteristics of inhalable bacteria in bioaerosols and antibiotic resistance genes in Harbin. Bioaerosols have received extensive attention due to their impact on climate, ecological environment, and human health. This study aimed to reveal the driving factors that structure bacterial community composition and the transmission route of antibiotic resistance genes (ARGs) in PM(2.5). The results showed that the bacterial concentration in spring (8.76 × 10(5) copies/m(3)) was significantly higher than that in summer (1.03 × 10(5) copies/m(3)) and winter (4.74 × 10(4) copies/m(3)). Low temperatures and air pollution in winter negatively affected bacterial concentrations. Keystone taxa were identified by network analysis. Although about 50 % of the keystone taxa had low relative abundances, the strong impact of complex interactions between keystone taxa and other taxa on bacterial community structure deserved attention. The bacterial community assembly was dominated by stochastic processes (79.3 %). Interactions between bacteria and environmental filtering together affected bacterial community composition. Vertical gene transfer played an important role in the transmission of airborne ARGs. Given the potential integration and expression of ARGs in recipients, the human exposure risk due to high concentrations of ARGs and mobile genetic elements cannot be ignored. This study highlights human exposure to inhalable bacterial pathogens and ARGs in urban areas.202336584645
685090.9996Fate of high-risk antibiotic resistance genes in large-scale aquaculture sediments: Geographical differentiation and corresponding drivers. Antibiotic resistance genes (ARGs), emerging environmental contaminants, have become challenges of public health security. However, the distribution and drivers of ARGs, especially high-risk ARGs, in large-scale aquaculture sediments remain unknown. Here, we collected sediment samples from 40 crayfish ponds in seven main crayfish culture provinces in China and then investigated the distribution and risk of ARGs based on high-throughput sequencing and quantitative PCR techniques. Our results suggested that aquaculture sediment was potential reservoir of ARGs and the abundance of aadA-02 was the highest. High-risk ARG (floR) was also prevalent in the sediment and was the most abundant in Jiangsu Province, where opportunistic pathogens were also enriched. The abundance of floR was positively correlated with different environmental factors, such as total phosphorus in water and total carbon in sediment. In addition, Mycobacterium sp., opportunistic pathogenic bacteria, might be potential host for floR. Furthermore, the potential propagation pathway of ARGs was from sediment to crayfish gut, and Bacteroidetes and Proteobacteria might be the main bacterial groups responsible for the proliferation of ARGs. Generally, our results illustrate that pond sediment may be an ARG reservoir of aquatic animals. Meanwhile, our study helps develop valuable strategies for accessing risks and managing ARGs.202337714353
6848100.9996Swine farming elevated the proliferation of Acinetobacter with the prevalence of antibiotic resistance genes in the groundwater. Swine farming generates a large amount of wastes containing various contaminants, resulting in environmental contamination and human health problems. Here we investigated the contamination profiles of antibiotics and antibiotic resistance genes (ARGs) as well as microbial community in groundwater of the two villages with or without swine farms, and then assessed the human exposure risks of antibiotics, ARGs and indicator bacteria through drinking groundwater. The results showed that swine farming could lead to enhanced concentration levels of various veterinary antibiotics and ARGs in the groundwater in comparison to the reference village without swine farming. The microbial diversity of groundwater was significantly decreased with predominance of conditional pathogens Acinetobacter (up to 90%) in some wells of the swine farming village. Meanwhile, the abundance of Acinetobacter was significantly correlated to bacterial abundance, ARGs and integrons. The local residents could ingest various antibiotic residues and ARGs as well as pathogens, with daily intake of Acinetobacter up to approximately 10 billion CFU/resident through drinking groundwater contaminated by swine farming. The findings from this study suggest potential health risks of changing gut microbial community and resistome by drinking contaminated groundwater.202031999967
3170110.9996A review of antibiotic resistance genes in major river basins in China: Distribution, drivers, and risk. Antibiotic resistance genes (ARGs) have complex transmission pathways and are prone to form multi-drug-resistant bacteria, threatening the ecological environment and human health. This paper elucidates the distribution and dissemination of ARGs across seven major river basins in China through a comprehensive analysis of relevant literature from the past decade. It presents a comprehensive catalog of pertinent risk assessment methodologies and potential management strategies aimed at mitigating the threat posed by antibiotic resistance due to ARGs. The analysis results showed that the pollution abundance of ARGs showed a decreasing trend from east to west, with the estuarine environment and economically developed areas standing out, with sulfonamides and tetracyclines, among others, as the main types of pollution. Human activities are closely related to the occurrence and spread of ARGs. Mobile genetic factors and microbial communities act as the main drivers to promote the proliferation of ARGs among different microorganisms through horizontal transfer and other pathways. The exhibition of ARGs assessment methods was comparatively analyzed, while Chinese river basins are at medium-high risk and need to be managed rationally. This review can provide a reference for the distribution, spread and management of ARGs in Chinese river basin.202540010590
6839120.9996Bioaerosol is an important transmission route of antibiotic resistance genes in pig farms. Although pig farms are hotspots of antibiotic resistance due to intensive use of antibiotics, little is known about the abundance, diversity and transmission of airborne antibiotic resistance genes (ARGs). This study reports that bioaerosol is an important spread route of ARGs in pig farms. ARGs, mobile genetic elements (MGEs), and bacterial communities were investigated in both air and feces samples during winter and summer. The average concentration of airborne ARGs and MGEs during winter is higher than that during summer when using the ventilation system. The tetM is identified as the predominant airborne ARG with abundance of 6.3 ± 1.2 log copies/m(3). Clostridium and Streptococcus are two dominant bacteria and several opportunistic pathogens are detected in air samples. High temperature is favorable for more diverse bacterial communities, but relative humidity has negative effects. The wind speed promotes the spread of airborne ARGs. The network analysis results show the average fecal contribution to airborne bacteria is 19.9% and 59.4% during summer and winter, respectively. Horizontal gene transfer plays an important role in the dissemination of airborne ARGs during winter (77.8% possibility), while a lower possibility of 12.0% in summer.202133864959
7048130.9996Airborne antibiotics, antimicrobial resistance, and bacterial pathogens in a commercial composting facility: Transmission and exposure risk. Multiple elements associated with antimicrobial resistance in compost may escape into the air during the composting process, including antibiotic resistance genes (ARGs), human pathogenic bacteria (HPBs), and even antibiotics. Although antibiotics play a critical role in the evolution of resistance in HPBs, no information is available on airborne antibiotics in composting facilities. In this study, we systematically quantified airborne antibiotics, ARGs, and HPBs in comparison with those in compost. The burden of antibiotics in the air reached 4.17 ± 2.71 × 10(2) ng/g, significantly higher than that in compost. The concentration of ARGs (10(2) copies/g) in air also increased compared with that in compost. Concentrations of target contaminants in air were affected by temperature, organic matter, and heavy metals. Co-occurrence network analysis revealed the connectivity and complexity of antibiotics, ARGs, and HPBs were greater in air than in compost. The maximum daily antibiotic intake dose was up to 1.18 × 10(-1)ng/d/kg, accompanied by considerable inhalation levels of ARGs and HPBs. Our results reveal the severity of airborne antimicrobial resistance (AMR) elements in composting facilities, highlight the non-negligible amount of antibiotics and their co-existence with ARGs and HPBs, and shed light on the potential role of airborne antibiotics in the evolution of environmental AMR.202439442303
6817140.9996Distribution of Antibiotic Resistance Genes in Karst River and Its Ecological Risk. In recent years, karst water has been polluted by emerging pollutants such as antibiotics. In this study, the bacterial communities and antibiotic resistance genes (ARGs) in antibiotics contaminated karst river was studied in summer and winter. The concentration of antibiotics in winter karst river is higher than that in summer, and there are significant differences in structure of bacterial community and ARGs between karst river water samples. Aminoglycoside, beta-lactamase and multidrug are the main types of ARGs, and transposons play an important role in the spread of ARGs. The horizontal gene transfer (HGT) of ARGs between bacteria mediated by mobile genetic elements (MGEs) would cause the spread of ARGs and bring potential ecological risks. In addition, we found that the risk of antibiotic resistant pathogenic bacteria (ARPB) in winter was possibly higher than that in summer. It was suggested that the discharge of antibiotics, water amount and seasonal occurrence time of human intestinal diseases affect the risks caused by antibiotics contaminants. This study helps us to understand the transmission mechanism of ARGs and their potential seasonal ecological risks in complex karst water systems.202134392041
7365150.9996A case study on the distribution of the environmental resistome in Korean shrimp farms. Hundreds of tons of antibiotics are widely used in aquaculture to prevent microbial infections and promote fish growth. However, the overuse of antibiotics and chemical products can lead to the selection and spreading of antibiotic-resistant bacteria (ARB) and antimicrobial resistance genes (ARGs), which are of great concern considering the threat to public health worldwide. Here, in-depth metagenome sequencing was performed to explore the environmental resistome and ARB distribution across farming stages in shrimp farms and examine anthropogenic effects in nearby coastal waters. A genome-centric analysis using a metagenome binning approach allowed us to accurately investigate the distribution of pathogens and ARG hosts in shrimp farms. The diversity of resistomes was higher in shrimp farms than in coastal waters, and the distribution of resistomes was dependent on the farming stage. In particular, the tetracycline resistance gene was found mainly at the early post-larval stage regardless of the farm. The metagenome-assembled genomes of Vibrio spp. were dominant at this stage and harbored tet34, which is known to confer resistance to oxytetracycline. In addition, opportunistic pathogens such as Francisella, Mycoplasma, Photobacterium, and Vibrio were found in abundance in shrimp farms, which had multiple virulence factors. This study highlights the increased resistance diversity and environmental selection of pathogens in shrimp farms. The use of environmental pollutants on farms may cause an increase in resistome diversity/abundance and the transmission of pathogens to the surrounding environment, which may pose future risks to public health and aquatic organisms.202134653940
7294160.9996The Sources and Potential Hosts Identification of Antibiotic Resistance Genes in the Yellow River, Revealed by Metagenomic Analysis. The fate of antibiotic resistance genes (ARGs) has been revealed in various environmental media in recent years. Namely, the emergence of genes that resist colistin and carbapenems has attracted wide attention. However, the pollution condition of ARGs and sources in the Yellow River is still little understood, despite the river being the second longest in China. The present study determined the levels of ARG pollution in the Henan section of the Yellow River and evaluated the role of the aquaculture industry in the spread of ARGs. As revealed by the results, a total of 9 types of ARGs were detected in the sediments of the Yellow River, and the total ARG content in the Yellow River ranges from 7.27 to 245.45 RPKM. Sul1 and sul2 are the dominant ARGs, and the huge usage of sulfonamides, horizontal gene transfer, and wide bacteria host contribute to the prevalence of these two genes. The results of Spearman correlation analysis indicate that the breeding industry has little influence on ARGs in the Yellow River. Network analysis reveals that the opportunistic pathogen Pseudomonas is the potential host of sul1, tetG, and ANT(3'')-IIa, which can pose a risk to human health.202236012061
6866170.9996Deciphering the antibiotic resistome in stratified source water reservoirs in China: Distribution, risk, and ecological drive. The proliferation and dissemination of antibiotic resistance genes (ARGs) in source water reservoirs may pose a threat to human health. This study investigated the antibiotic resistance in stratified reservoirs in China across different seasons and spatial locations. In total, 120 ARG subtypes belonging to 15 ARG types were detected with an abundance ranging from 171.06 to 793.71 × /Gb. Multidrug, tetracycline, aminoglycoside, and bacitracin resistance genes were dominant in the reservoirs. The abundance and transfer potential of ARGs were notably higher, especially during the stratified period, with markedly elevated levels in the bottom layer compared to the surface layer. Metagenomic assembly yielded 1357 ARG-carrying contigs, belonging to 83 resistant bacterial species, of which 13 were identified as human pathogen bacteria (HPB). HPB hosts (Sphingomonas sp., Burkholderiales sp., and Ralstonia sp., etc.) were super carriers of ARGs. Genes including ompR, bacA, golS, and ugd carried on HPB plasmids exhibited higher abundance in the water, warranting attention to the risk of resistance transmission. Environmental pressures have caused a shift in the assembly mechanism of ARGs, transitioning from a random process in surface water to a deterministic process in bottom water. The results of this study will deepen people's understanding of the ARG risk in stratified reservoirs.202539673943
6863180.9996Prevalence, source and risk of antibiotic resistance genes in the sediments of Lake Tai (China) deciphered by metagenomic assembly: A comparison with other global lakes. Lakes are one of the natural reservoirs of antibiotic resistance genes (ARGs) in environments. Long retention times in lakes potentially allow ARGs to persist and may create increased opportunities for the emergence of resistant pathogens. In this study, we investigated the prevalence, source and dissemination risk of ARGs in the sediments of a typical urban lake, Lake Tai (China) which has been a drastic example of water pollution with eutrophication in the world due to its proliferated cyanobacterial blooms. High-throughput profilings of ARGs in the sediments of Lake Tai were characterized with metagenomic assembly, and were compared with those in other global lakes from Australia, Canada, Indonesia, Rwanda and the United States of America. The hosts of ARGs in the sediments of Lake Tai were explored based on the taxonomic annotation of ARG-carrying contigs and network analysis, and a novel recently-discovered crAssphage was employed for source tracking of resistance bacteria. Meanwhile, the potential resistome risk was identified by projecting the co-occurrence of acquired ARGs, mobile genetic elements (MGEs) and human bacterial pathogens into a three-dimensional exposure space. Results showed 321 ARG subtypes belonging to 21 ARG types were detected in the sediments of Lake Tai, dominated by multidrug, macrolide-lincosamide-streptogramin, bacitracin, quinolone, mupirocin and trimethoprim resistance genes. Relatively, the ARG levels in the sediments of Lake Tai were significantly higher than those in other global lakes. Source tracking showed the coverages of detected crAssphage in the sediments of Lake Tai were positively correlated with the total ARG coverage, suggesting the contribution of human fecal contamination to the prevalence of ARGs in this lake. It should be noted that the co-occurrence ratio of ARGs, MGEs and human pathogens in the sediments of Lake Tai was higher than that in other global lakes, likely indicating a higher risk for the resistance dissemination in the China's third largest freshwater lake.201930928850
6889190.9996Hot spots of resistance: Transit centers as breeding grounds for airborne ARG-carrying bacteriophages. The presence of pathogenic bacteria and antibiotic resistance genes (ARGs) in urban air poses a significant threat to public health. While prevailing research predominantly focuses on the airborne transmission of ARGs by bacteria, the potential influence of other vectors, such as bacteriophages, is often overlooked. This study aims to investigate the characteristics of phages and ARGs in aerosols originating from hospitals, public transit centers, wastewater treatment plants, and landfill sites. The average abundance of ARGs carried by phages in the public transit centers was 8.81 ppm, which was 2 to 3 times higher than that at the other three sites. Additionally, the abundance of ARGs across different risk levels at this site was also significantly higher than at the other three sites. The assembled phage communities bearing ARGs in public transit centers are chiefly governed by homogeneous selection processes, likely influenced by human movement. Furthermore, observations at public transit sites revealed that the average abundance ratio of virulent phages to their hosts was 1.01, and the correlation coefficient between their auxiliary metabolic genes and hosts' metabolic genes was 0.59, which were 20 times and 3 times higher, respectively, than those of temperate phages. This suggests that virulent phages may enhance their survival by altering host metabolism, thereby aiding the dispersion of ARGs and bacterial resistance. These revelations furnish fresh insights into phage-mediated ARG transmission, offering scientific substantiation for strategies aimed at preventing and controlling resistance within aerosols.202439418908