# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 3856 | 0 | 1.0000 | Food-borne microbes influence conjugative transfer of antimicrobial resistance plasmids in pre-disturbed gut microbiome. Ingestion of antibiotic-resistant bacteria following antibiotic treatments may lead to the transfer of antimicrobial resistance genes (ARGs) within a disturbed gut microbiota. However, it remains unclear whether and how microbes present in food matrices influence ARG transfer. Thus, a previously established mouse model, which demonstrated the conjugative transfer of a multi-drug resistance plasmid (pIncA/C) from Salmonella Heidelberg (donor) to Salmonella Typhimurium (recipient), was used to assess the effects of food-borne microbes derived from fresh carrots on pIncA/C transfer. Mice were pre-treated with ampicillin, streptomycin, sulfamethazine, or left untreated as a control to facilitate bacterial colonization. Contrary to previous findings where high-density colonization of the donor and recipient bacteria occurred in the absence of food-borne microbes, the presence of these microbes resulted in a low abundance of S. Typhimurium and no detection of S. Typhimurium transconjugants in the fecal samples from any of the mice. However, in mice pre-treated with streptomycin, a significant reduction in microbial species richness allowed for the significant enrichment of Enterobacteriaceae and pIncA/C transfer to bacteria from the genera Escherichia, Enterobacter, Citrobacter, and Proteus. These findings suggest that food-borne microbes may enhance ARG dissemination by influencing the population dynamics of bacterial hosts within a pre-disturbed gut microbiome. | 2025 | 40315481 |
| 3861 | 1 | 0.9999 | Dietary intake of enrofloxacin promotes the spread of antibiotic resistance from food to simulated human gut. Antibiotic residues are commonly found in food. The effect of dietary exposure to veterinary antibiotics on the transmission of antibiotic resistant bacteria and antibiotic resistance genes from food to humans is unknown. We found that dietary exposure to enrofloxacin reduced microbial diversity, interactions and the immune responses, weakened the colonization resistance of the resident microbiota, and promoted the colonization of exogenous Escherichia coli K-12 MG1655 in the simulated human intestine both in vitro and in vivo experiments in mice. In addition to the growth advantages for potential most likely bacterial hosts of ARGs under enrofloxacin exposure, the dietary exposure to enrofloxacin promoted horizontal transfer of resistance plasmids and altered the simulated human gut antibiotic resistome in a time-dependent manner. Collectively, these findings demonstrated that dietary intake of enrofloxacin promoted the colonization of E. coli K-12 MG1655 in the simulated human intestine and the horizontal transfer of antibiotic resistance genes, highlighting the risk of antibiotic resistance transmission from food to humans mediated by dietary exposure to veterinary antibiotics. | 2025 | 40121546 |
| 3857 | 2 | 0.9999 | How Gut Microbiome Perturbation Caused by Antibiotic Pre-Treatments Affected the Conjugative Transfer of Antimicrobial Resistance Genes. The global spread of antimicrobial resistance genes (ARGs) poses a significant threat to public health. While antibiotics effectively treat bacterial infections, they can also induce gut dysbiosis, the severity of which varies depending on the specific antibiotic treatment used. However, it remains unclear how gut dysbiosis affects the mobility and dynamics of ARGs. To address this, mice were pre-treated with streptomycin, ampicillin, or sulfamethazine, and then orally inoculated with Salmonella enterica serovar Typhimurium and S. Heidelberg carrying a multi-drug resistance IncA/C plasmid. The streptomycin pre-treatment caused severe microbiome perturbation, promoting the high-density colonization of S. Heidelberg and S. Typhimurium, and enabling an IncA/C transfer from S. Heidelberg to S. Typhimurium and a commensal Escherichia coli. The ampicillin pre-treatment induced moderate microbiome perturbation, supporting only S. Heidelberg colonization and the IncA/C transfer to commensal E. coli. The sulfamethazine pre-treatment led to mild microbiome perturbation, favoring neither Salmonella spp. colonization nor a conjugative plasmid transfer. The degree of gut dysbiosis also influenced the enrichment or depletion of the ARGs associated with mobile plasmids or core commensal bacteria, respectively. These findings underscore the significance of pre-existing gut dysbiosis induced by various antibiotic treatments on ARG dissemination and may inform prudent antibiotic use practices. | 2024 | 39597538 |
| 7399 | 3 | 0.9998 | Aquatic animals promote antibiotic resistance gene dissemination in water via conjugation: Role of different regions within the zebra fish intestinal tract, and impact on fish intestinal microbiota. The aqueous environment is one of many reservoirs of antibiotic resistance genes (ARGs). Fish, as important aquatic animals which possess ideal intestinal niches for bacteria to grow and multiply, may ingest antibiotic resistance bacteria from aqueous environment. The fish gut would be a suitable environment for conjugal gene transfer including those encoding antibiotic resistance. However, little is known in relation to the impact of ingested ARGs or antibiotic resistance bacteria (ARB) on gut microbiota. Here, we applied the cultivation method, qPCR, nuclear molecular genetic marker and 16S rDNA amplicon sequencing technologies to develop a plasmid-mediated ARG transfer model of zebrafish. Furthermore, we aimed to investigate the dissemination of ARGs in microbial communities of zebrafish guts after donors carrying self-transferring plasmids that encode ARGs were introduced in aquaria. On average, 15% of faecal bacteria obtained ARGs through RP4-mediated conjugal transfer. The hindgut was the most important intestinal region supporting ARG dissemination, with concentrations of donor and transconjugant cells almost 25 times higher than those of other intestinal segments. Furthermore, in the hindgut where conjugal transfer occurred most actively, there was remarkable upregulation of the mRNA expression of the RP4 plasmid regulatory genes, trbBp and trfAp. Exogenous bacteria seem to alter bacterial communities by increasing Escherichia and Bacteroides species, while decreasing Aeromonas compared with control groups. We identified the composition of transconjugants and abundance of both cultivable and uncultivable bacteria (the latter accounted for 90.4%-97.2% of total transconjugants). Our study suggests that aquatic animal guts contribute to the spread of ARGs in water environments. | 2017 | 28742284 |
| 3714 | 4 | 0.9998 | Effect of conjugative transfer of antibiotic resistance genes mediated by plasmids on the microecology of different intestinal segments. INTRODUCTION: The conjugative transfer of antibiotic resistance genes (ARGs) mediated by plasmids occurred in different intestinal segments of mice was explored. METHODS: The location of ARG donor bacteria and ARGs was investigated by qPCR, flow cytometry, and small animal imaging. The resistant microbiota was analyzed by 16S rRNA gene amplification sequencing. RESULTS: The small intestine was the main site for the location of ARG donor bacteria and ARGs. The intestinal microbiota richness of the small intestine (duodenum and jejunum) and the large intestine (cecum, colon, and rectum) increased, and the ileum microbiota richness decreased under the action of donor bacteria. The differences in the number of bacteria in the small intestine and the large intestine, as well as the relative richness of Firmicutes from the small intestine to the large intestine, decreased. By contrast, the relative abundance of Proteobacteria increased. The intake of resistant plasmids alleviated the impact of antibiotics on intestinal microbiota, particularly increasing the proportion of Proteobacteria and Bacteroides, which were presumed to be susceptible to ARGs. DISCUSSION: The acquisition of ARGs by intestinal microbes is an important reason why infectious diseases are difficult to cure, which brings risks to human health and intestinal microecology. | 2024 | 39764443 |
| 3464 | 5 | 0.9998 | Persistence of Marine Bacterial Plasmid in the House Fly (Musca domestica): Marine-Derived Antimicrobial Resistance Genes Have a Chance of Invading the Human Environment. The house fly is known to be a vector of antibiotic-resistant bacteria (ARB) in animal farms. It is also possible that the house fly contributes to the spread of ARB and antibiotic resistance genes (ARGs) among various environments. We hypothesized that ARB and ARGs present in marine fish and fishery food may gain access to humans via the house fly. We show herein that pAQU1, a marine bacterial ARG-bearing plasmid, persists in the house fly intestine for 5 days after fly ingestion of marine bacteria. In the case of Escherichia coli bearing the same plasmid, the persistence period exceeded 7 days. This interval is sufficient for transmission to human environments, meaning that the house fly is capable of serving as a vector of marine-derived ARGs. Time course monitoring of the house fly intestinal microflora showed that the initial microflora was occupied abundantly with Enterobacteriaceae. Experimentally ingested bacteria dominated the intestinal environment immediately following ingestion; however, after 72 h, the intestinal microflora recovered to resemble that observed at baseline, when diverse genera of Enterobacteriaceae were seen. Given that pAQU1 in marine bacteria and E. coli were detected in fly excrement (defined here as any combination of feces and regurgitated material) at 7 days post-bacterial ingestion, we hypothesize that the house fly may serve as a vector for transmission of ARGs from marine items and fish to humans via contamination with fly excrement. | 2024 | 38191744 |
| 7400 | 6 | 0.9998 | Investigating the effects of municipal and hospital wastewaters on horizontal gene transfer. Horizontal gene transfer (HGT) plays an important role in the dissemination of antibiotic resistance genes. In sewer systems, human-associated and environmental bacteria are mixed together and exposed to many substances known to increase HGT, including various antibacterial compounds. In wastewaters, those substances are most often detected below concentrations known to induce HGT individually. Still, it is possible that such wastewaters induce HGT, for example via mixture effects. Here, a panel of antibiotics, biocides and other pharmaceuticals was measured in filter-sterilized municipal and hospital wastewater samples from Gothenburg, Sweden. The effects on HGT of the chemical mixtures in these samples were investigated by exposing a complex bacterial donor community together with a GFP-tagged E. coli recipient strain. Recipients that captured sulfonamide resistance-conferring mobile genetic elements (MGEs) from the bacterial community were enumerated and characterized by replicon typing, antibiotic susceptibility testing and long read sequencing. While exposure to municipal wastewater did not result in any detectable change in HGT rates, exposure to hospital wastewater was associated with an increase in the proportion of recipients that acquired sulfonamide resistance but also a drastic decrease in the total number of recipients. Although, concentrations were generally higher in hospital than municipal wastewater, none of the measured substances could individually explain the observed effects of hospital wastewater. The great majority of the MGEs captured were IncN plasmids, and resistance to several antibiotics was co-transferred in most cases. Taken together, the data show no evidence that chemicals present in the studied municipal wastewater induce HGT. Still, the increased relative abundance of transconjugants after exposure to hospital wastewater could have implications for the risks of both emergence and transmission of resistant bacteria. | 2021 | 33631686 |
| 3862 | 7 | 0.9998 | Interaction of tetracycline and copper co-intake in inducing antibiotic resistance genes and potential pathogens in mouse gut. The widespread use of copper and tetracycline as growth promoters in the breeding industry poses a potential threat to environmental health. Nevertheless, to the best of our knowledge, the potential adverse effects of copper and tetracycline on the gut microbiota remain unknown. Herein, mice were fed different concentrations of copper and/or tetracycline for 6 weeks to simulate real life-like exposure in the breeding industry. Following the exposure, antibiotic resistance genes (ARGs), potential pathogens, and other pathogenic factors were analyzed in mouse feces. The co-exposure of copper with tetracycline significantly increased the abundance of ARGs and enriched more potential pathogens in the gut of the co-treated mice. Copper and/or tetracycline exposure increased the abundance of bacteria carrying either ARGs, metal resistance genes, or virulence factors, contributing to the widespread dissemination of potentially harmful genes posing a severe risk to public health. Our study provides insights into the effects of copper and tetracycline exposure on the gut resistome and potential pathogens, and our findings can help reduce the risks associated with antibiotic resistance under the One Health framework. | 2024 | 38527398 |
| 7398 | 8 | 0.9998 | Spread of chloramphenicol and tetracycline resistance genes by plasmid mobilization in agricultural soil. Spread of antibiotic resistance genes (ARGs) poses a worldwide threat to public health and food safety. However, ARG spread by plasmid mobilization, a broad host range transfer system, in agricultural soil has received little attention. Here, we investigated the spread of chloramphenicol resistance gene (CRG) and tetracycline resistance gene (TRG) in agricultural soil by mobilization of pSUP106 under different conditions, including different concentrations of nutrients, temperatures, soil depths, rhizosphere soils, and soil types. The number of resistant bacteria isolated in non-sterilized soil from the experiments was approximately 10(4) to 10(7) per gram of soil, belonging to 5-10 species from four genera, including nonpathogen, opportunistic pathogen, pathogen bacteria, and gram-positive and gram-negative bacteria, depending on the experiment conditions. In sterilized soil, higher levels of nutrients and higher temperatures promoted plasmid mobilization and ARG expression. Topsoil and deep soil might not support the spread of antibiotic resistance, while ARG dissemination by plasmid mobilization was better supported by maize rhizosphere and loam soils. All these factors might change bacterial growth and the activity of bacteria and lead to the above influence. Introduction of only the donor and helper, or the donor alone also resulted in the transfer of ARGs and large numbers of antibiotic resistant bacteria (ARB), indicating that some indigenous bacteria contain the elements necessary for plasmid mobilization. Our results showed that plasmid mobilization facilitated dissemination of ARGs and ARB in soil, which led to the disturbance of indigenous bacterial communities. It is important to clear ARG dissemination routes and inhibit the spread of ARGs. | 2020 | 31991360 |
| 7384 | 9 | 0.9998 | Uncovering antimicrobial resistance in three agricultural biogas plants using plant-based substrates. Antimicrobial resistance (AMR) is becoming an increasing global concern and the anaerobic digestion (AD) process represents a potential transmission route when digestates are used as fertilizing agents. AMR contaminants, e.g. antibiotic-resistant bacteria (ARB) and plasmid-mediated antibiotic resistance genes (ARGs) have been found in different substrates and AD systems, but not yet been investigated in plant-based substrates. AMR transfer from soils to vegetable microbiomes has been observed, and thus crop material potentially represents a so far neglected AMR load in agricultural AD processes, contributing to AMR spread. In order to test this hypothesis, this study examined the AMR situation throughout the process of three biogas plants using plant-based substrates only, or a mixture of plant-based and manure substrates. The evaluation included a combination of culture-independent and -dependent methods, i.e., identification of ARGs, plasmids, and pathogenic bacteria by DNA arrays, and phylogenetic classification of bacterial isolates and their phenotypic resistance pattern. To our knowledge, this is the first study on AMR in plant-based substrates and the corresponding biogas plant. The results showed that the bacterial community isolated from the investigated substrates and the AD processing facilities were mainly Gram-positive Bacillus spp. Apart from Pantoea agglomerans, no other Gram-negative species were found, either by bacteria culturing or by DNA typing array. In contrast, the presence of ARGs and plasmids clearly indicated the existence of Gram-negative pathogenic bacteria, in both substrate and AD process. Compared with substrates, digestates had lower levels of ARGs, plasmids, and culturable ARB. Thus, digestate could pose a lower risk of spreading AMR than substrates per se. In conclusion, plant-based substrates are associated with AMR, including culturable Gram-positive ARB and Gram-negative pathogenic bacteria-associated ARGs and plasmids. Thus, the AMR load from plant-based substrates should be taken into consideration in agricultural biogas processing. | 2022 | 35306061 |
| 7408 | 10 | 0.9998 | Effects of Dietary Antimicrobial Growth Promoters on Performance Parameters and Abundance and Diversity of Broiler Chicken Gut Microbiome and Selection of Antibiotic Resistance Genes. Antimicrobial growth promoters (AGPs) are commonly used in broiler production. There is a huge societal concern around their use and their contribution to the proliferation of antimicrobial resistance (AMR) in food-producing animals and dissemination to humans or the environment. However, there is a paucity of comprehensive experimental data on their impact on poultry production and the AMR resistome. Here, we investigated the effect of five antimicrobial growth promoters (virginiamycin, chlortetracycline, bacitracin methyl disalicylate, lincomycin, and tylosin) used in the commercial broiler production in the Indian subcontinent and in the different parts of the world for three consecutive production cycles on performance variables and also the impact on gut bacteria, bacteriophage, and resistome profile using culture-independent approaches. There was no significant effect of AGPs on the cumulative growth or feed efficiency parameters at the end of the production cycles and cumulative mortality rates were also similar across groups. Many antibiotic resistance genes (ARGs) were ubiquitous in the chicken gut irrespective of AGP supplementation. In total, 62 ARGs from 15 antimicrobial classes were detected. Supplementation of AGPs influenced the selection of several classes of ARGs; however, this was not correlated necessarily with genes relevant to the AGP drug class; some AGPs favored the selection of ARGs related to antimicrobials not structurally related to the AGP. AGPs did not impact the gut bacterial community structure, including alpha or beta diversity significantly, with only 16-20 operational taxonomic units (OTUs) of bacteria being altered significantly. However, several AGPs significantly reduced the population density of some of the potential pathogenic genera of bacteria, such as Escherichia coli. Chlortetracycline increased the abundance of Escherichia phage, whereas other AGPs did not influence the abundance of bacteriophage significantly. Considering the evidence that AGPs used in poultry production can select for resistance to more than one class of antimicrobial resistance, and the fact that their effect on performance is not significant, their use needs to be reduced and there is a need to monitor the spread of ARGs in broiler chicken farms. | 2022 | 35783415 |
| 3149 | 11 | 0.9998 | Effect of a probiotic and an antibiotic on the mobilome of the porcine microbiota. Introduction: To consider the growing health issues caused by antibiotic resistance from a "one health" perspective, the contribution of meat production needs to be addressed. While antibiotic resistance is naturally present in microbial communities, the treatment of farm animals with antibiotics causes an increase in antibiotic resistance genes (ARG) in the gut microbiome. Pigs are among the most prevalent animals in agriculture; therefore, reducing the prevalence of antibiotic-resistant bacteria in the pig gut microbiome could reduce the spread of antibiotic resistance. Probiotics are often studied as a way to modulate the microbiome and are, therefore, an interesting way to potentially decrease antibiotic resistance. Methods: To assess the efficacy of a probiotic to reduce the prevalence of ARGs in the pig microbiome, six pigs received either treatment with antibiotics (tylvalosin), probiotics (Pediococcus acidilactici MA18/5M; Biopower(®) PA), or a combination of both. Their faeces and ileal digesta were collected and DNA was extracted for whole genome shotgun sequencing. The reads were compared with taxonomy and ARG databases to identify the taxa and resistance genes in the samples. Results: The results showed that the ARG profiles in the faeces of the antibiotic and combination treatments were similar, and both were different from the profiles of the probiotic treatment (p < 0.05). The effects of the treatments were different in the digesta and faeces. Many macrolide resistance genes were detected in a higher proportion in the microbiome of the pigs treated with antibiotics or the combination of probiotics and antibiotics. Resistance-carrying conjugative plasmids and horizontal transfer genes were also amplified in faeces samples for the antibiotic and combined treatments. There was no effect of treatment on the short chain fatty acid content in the digesta or the faeces. Conclusion: There is no positive effect of adding probiotics to an antibiotic treatment when these treatments are administered simultaneously. | 2024 | 38606356 |
| 3851 | 12 | 0.9998 | Impacts of florfenicol on the microbiota landscape and resistome as revealed by metagenomic analysis. BACKGROUND: Drug-resistant fish pathogens can cause significant economic loss to fish farmers. Since 2012, florfenicol has become an approved drug for treating both septicemia and columnaris diseases in freshwater fish. Due to the limited drug options available for aquaculture, the impact of the therapeutical florfenicol treatment on the microbiota landscape as well as the resistome present in the aquaculture farm environment needs to be evaluated. RESULTS: Time-series metagenomic analyses were conducted to the aquatic microbiota present in the tank-based catfish production systems, in which catfish received standard therapeutic 10-day florfenicol treatment following the federal veterinary regulations. Results showed that the florfenicol treatment shifted the structure of the microbiota and reduced the biodiversity of it by acting as a strong stressor. Planctomycetes, Chloroflexi, and 13 other phyla were susceptible to the florfenicol treatment and their abundance was inhibited by the treatment. In contrast, the abundance of several bacteria belonging to the Proteobacteria, Bacteroidetes, Actinobacteria, and Verrucomicrobia phyla increased. These bacteria with increased abundance either harbor florfenicol-resistant genes (FRGs) or had beneficial mutations. The florfenicol treatment promoted the proliferation of florfenicol-resistant genes. The copy number of phenicol-specific resistance genes as well as multiple classes of antibiotic-resistant genes (ARGs) exhibited strong correlations across different genetic exchange communities (p < 0.05), indicating the horizontal transfer of florfenicol-resistant genes among these bacterial species or genera. Florfenicol treatment also induced mutation-driven resistance. Significant changes in single-nucleotide polymorphism (SNP) allele frequencies were observed in membrane transporters, genes involved in recombination, and in genes with primary functions of a resistance phenotype. CONCLUSIONS: The therapeutical level of florfenicol treatment significantly altered the microbiome and resistome present in catfish tanks. Both intra-population and inter-population horizontal ARG transfer was observed, with the intra-population transfer being more common. The oxazolidinone/phenicol-resistant gene optrA was the most prevalent transferred ARG. In addition to horizontal gene transfer, bacteria could also acquire florfenicol resistance by regulating the innate efflux systems via mutations. The observations made by this study are of great importance for guiding the strategic use of florfenicol, thus preventing the formation, persistence, and spreading of florfenicol-resistant bacteria and resistance genes in aquaculture. | 2019 | 31818316 |
| 3255 | 13 | 0.9998 | Early life dynamics of ARG and MGE associated with intestinal virome in neonatal piglets. The pre- and post-weaning stages for piglets are critical periods for the maturation of intestinal functions and contamination with antibiotic resistant bacterial pathogens will threaten their intestinal health. The presence of bacteriophage can also alter bacterial populations in the intestine but whether transmission of antibiotic resistance genes (ARG) is affected by phage during maturation of the neonatal piglet intestine is not known. We therefore identified the intestinal virome along with ARGs and mobile genetic elements (MGE) from piglet fecal samples collected from 3 to 28 days representing the different growth stages. We found wide fluctuations for the intestinal virome of weaning piglets and most virus - related antibiotic resistance was derived from temperate phage suggesting a reservoir of multidrug resistance was present in the neonatal porcine gut. Our results provide a comprehensive understanding of ARGs associated with the intestinal virome that therefore represents a potential risk for horizontal ARG transfer to pathogenic bacteria. | 2022 | 36191572 |
| 3859 | 14 | 0.9998 | Co-selection of antibiotic resistance via copper shock loading on bacteria from a drinking water bio-filter. Heavy metal contamination of source water frequently occurred in developing countries as a result of accidents. To address the problems, most of the previous studies have focused on engineering countermeasures. In this study, we investigated the effects of heavy metals, particularly copper, on the development of antibiotic resistance by establishing a copper shock loading test. Results revealed that co-selection occurred rapidly within 6 h. Copper, at the levels of 10 and 100 mg/L, significantly increased bacterial resistance to the antibiotics tested, including rifampin, erythromycin, kanamycin, and a few others. A total of 117 antimicrobial-resistance genes were detected from 12 types of genes, and the relative abundance of most genes (particularly mobile genetic elements intⅠand transposons) was markedly enriched by at least one fold. Furthermore, the copper shock loading altered the bacterial community. Numerous heavy metal and antibiotic resistant strains were screened out and enriched. These strains are expected to enhance the overall level of resistance. More noticeably, the majority of the co-selected antibiotic resistance could sustain for at least 20 h in the absence of copper and antimicrobial drugs. Resistance to vancomycin, erythromycin and lincomycin even could remain for 7 days. The prominent selection pressure by the copper shock loading implies that a real accident most likely poses similar impacts on the water environment. An accidental release of heavy metals would not only cause harm to the ecological environment, but also contribute to the development of bacterial antibiotic resistance. Broader concerns should be raised about the biological risks caused by sudden releases of pollutants by accidents. | 2018 | 29059628 |
| 3257 | 15 | 0.9997 | The effect of antibiotics on the gut microbiome: a metagenomics analysis of microbial shift and gut antibiotic resistance in antibiotic treated mice. BACKGROUND: Emergence of antibiotic resistance is a global public health concern. The relationships between antibiotic use, the gut community composition, normal physiology and metabolism, and individual and public health are still being defined. Shifts in composition of bacteria, antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) after antibiotic treatment are not well-understood. METHODS: This project used next-generation sequencing, custom-built metagenomics pipeline and differential abundance analysis to study the effect of antibiotic monotherapy on resistome and taxonomic composition in the gut of Balb/c mice infected with E. coli via transurethral catheterization to investigate the evolution and emergence of antibiotic resistance. RESULTS: There is a longitudinal decrease of gut microbiota diversity after antibiotic treatment. Various ARGs are enriched within the gut microbiota despite an overall reduction of the diversity and total amount of bacteria after antibiotic treatment. Sometimes treatment with a specific class of antibiotics selected for ARGs that resist antibiotics of a completely different class (e.g. treatment of ciprofloxacin or fosfomycin selected for cepA that resists ampicillin). Relative abundance of some MGEs increased substantially after antibiotic treatment (e.g. transposases in the ciprofloxacin group). CONCLUSIONS: Antibiotic treatment caused a remarkable reduction in diversity of gut bacterial microbiota but enrichment of certain types of ARGs and MGEs. These results demonstrate an emergence of cross-resistance as well as a profound change in the gut resistome following oral treatment of antibiotics. | 2020 | 32228448 |
| 3715 | 16 | 0.9997 | Deposition of resistant bacteria and resistome through FMT in germ-free piglets. Faecal microbiota transplantation (FMT) has received considerable attention in recent years due to its remarkable efficacy in restoring a normal gut microbiome. Here, we established the groups of post-FMT recipient piglets using germ-free piglets during early life to characterize the colonization of gut microbiota composition and the enrichment of resistance gene acquisition. By metagenomic analysis, we identified 115 bacterial phyla and 2111 bacterial genera that were acquired by the FMT recipients. We found that early-life microbial colonization and the spread of resistomes in recipient piglets were age dependent. A total of 425, 425 and 358 AR genes primarily belonging to 114, 114 and 102 different types were detected in the donors, post-FMT recipients in the FMT-3D group and post-FMT recipients in the FMT-15D group respectively. Genes that encoded tetracycline, macrolide and chloramphenicol resistance proteins were the most dominant AR genes, and the results corresponded with the exposure of antibiotic consumption at farm. Bacteroides, Escherichia, Clostridium, Parabacteroides, Treponema, Lactobacillus and Enterococcus were significantly correlated with the distribution of AR genes. More importantly, the relative abundance of AR genes was positively correlated with the levels of mobile genetic elements. Our results indicate that early-life microbial colonization can persistently shape the gut microbiota and antibiotic resistome. | 2021 | 33894059 |
| 7383 | 17 | 0.9997 | Spread of plasmids carrying antibiotic resistance genes in soil-lettuce-snail food chain. Fertilization can change the composition of antibiotic resistance genes(ARGs) and their host bacteria in agricultural fields, while complex microbial activities help ARGs into crops and transmit them to humans through agricultural products.Therefore, this study constructed a farmland food chain with soil-lettuce-snail as a typical structure, added genetically engineered Pseudomonas fluorescens containing multidrug-resistant plasmid RP4 to track its spread in the farmland food chain, and used different fertilization methods to explore its influence on the spread and diffusion of ARGs and intl1 in the farmland food chain. It was found that exogenous Pseudomonas can enter plants from soil and pass into snails' intestines, and there is horizontal gene transfer phenomenon of RP4 plasmid in bacteria. At different interfaces of the constructed food chain, the addition of exogenous drug-resistant bacteria had different effects on the total abundance of ARGs and intl1. Fertilization, especially manure, not only promoted the spread of Pseudomonas aeruginosa and the transfer of RP4 plasmid levels, but also significantly increased the total abundance of ARGs and intl1 at all interfaces of the constructed food chain. The main ARGs host bacteria in the constructed food chain include Proteobacteria, Bacteroides, and Firmicutes, while Flavobacterium of Bacteroides is the unique potential host bacteria of RP4 plasmid. In conclusion, this study provides a reference for the risk assessment of ARGs transmitted to the human body through the food chain, and has important practical significance to reduce the antibiotic resistance contamination of agricultural products and ensure the safety of vegetable basket. | 2024 | 38700770 |
| 3680 | 18 | 0.9997 | Metagenomic Insights Into the Contribution of Phages to Antibiotic Resistance in Water Samples Related to Swine Feedlot Wastewater Treatment. In this study, we examined the types of antibiotic resistance genes (ARGs) possessed by bacteria and bacteriophages in swine feedlot wastewater before and after treatment using a metagenomics approach. We found that the relative abundance of ARGs in bacterial DNA in all water samples was significantly higher than that in phages DNA (>10.6-fold), and wastewater treatment did not significantly change the relative abundance of bacterial- or phage-associated ARGs. We further detected the distribution and diversity of the different types of ARGs according to the class of antibiotics to which they confer resistance, the tetracycline resistance genes were the most abundant resistance genes and phages were more likely to harbor ATP-binding cassette transporter family and ribosomal protection genes. Moreover, the colistin resistance gene mcr-1 was also detected in the phage population. When assessing the contribution of phages in spreading different groups of ARGs, β-lactamase resistance genes had a relatively high spreading ability even though the abundance was low. These findings possibly indicated that phages not only could serve as important reservoir of ARG but also carry particular ARGs in swine feedlot wastewater, and this phenomenon is independent of the environment. | 2018 | 30459724 |
| 7388 | 19 | 0.9997 | Poultry manure-derived microorganisms as a reservoir and source of antibiotic resistance genes transferred to soil autochthonous microorganisms. Animal husbandry is increasing yearly due to the growing demand for meat and livestock products, among other reasons. To meet these demands, prophylactic antibiotics are used in the livestock industry (i.e., poultry farming) to promote health and stimulate animal growth. However, antibiotics are not fully metabolized by animals, and they are evacuated to the environment with excreta. Animal manure is used as fertilizer to reduce the volume of waste generated in the livestock sector. However, manure often contains microorganisms harboring antibiotic resistance genes (ARGs). Then, the microbiome of manure applicate to the soil may contribute to the spread of antibiotic resistance in the environment, including autochthonous soil-dwelling microorganisms. The present study was conducted during the crops growing season in Poland (May to September 2019) to determine the influence of poultry manure as well as poultry manure supplemented with selected antibiotics on the diversity of the soil microbiome in treatments that had not been previously fertilized with manure and the ability of antibiotic-resistant bacteria to transfer ARGs to other soil bacteria. Antibiotic concentrations were elevated at the beginning of the study and decreased over time. Poultry manure induced significant changes in the structure of microbial communities in soil; the diversity of the soil microbiome decreased, and the abundance of bacterial genera Bradyrhizobium, Streptomyces, and Pseudomonas, which are characteristic of the analyzed manure, increased. Over time, soil microbial diversity was restored to the state observed before the application of manure. Genes conferring resistance to multiple drugs as well as genes encoding resistance to bacitracin and aminoglycosides were the most frequently identified ARGs in the analyzed bacteria, including on mobile genetic elements. Multidrug resistance was observed in 17 bacterial taxa, whereas ARGs were identified in 32 bacterial taxa identified in the soil microbiome. The results of the study conclude that the application of poultry manure supplemented with antibiotics initially affects soil microbiome and resistome diversity but finally, the soil shows resilience and returns to its original state after time, with most antibiotic resistance genes disappearing. This phenomenon is of great importance in sustainable soil health after manure application. | 2023 | 37832303 |