# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 8714 | 0 | 0.9833 | Tales from the tomb: the microbial ecology of exposed rock surfaces. Although a broad diversity of eukaryotic and bacterial taxa reside on rock surfaces where they can influence the weathering of rocks and minerals, these communities and their contributions to mineral weathering remain poorly resolved. To build a more comprehensive understanding of the diversity, ecology and potential functional attributes of microbial communities living on rock, we sampled 149 tombstones across three continents and analysed their bacterial and eukaryotic communities via marker gene and shotgun metagenomic sequencing. We found that geographic location and climate were important factors structuring the composition of these communities. Moreover, the tombstone-associated microbial communities varied as a function of rock type, with granite and limestone tombstones from the same cemeteries harbouring taxonomically distinct microbial communities. The granite and limestone-associated communities also had distinct functional attributes, with granite-associated bacteria having more genes linked to acid tolerance and chemotaxis, while bacteria on limestone were more likely to be lichen associated and have genes involved in photosynthesis and radiation resistance. Together these results indicate that rock-dwelling microbes exhibit adaptations to survive the stresses of the rock surface, differ based on location, climate and rock type, and seem pre-disposed to different ecological strategies (symbiotic versus free-living lifestyles) depending on the rock type. | 2018 | 29235707 |
| 6836 | 1 | 0.9830 | Microbiome and antibiotic resistome in household dust from Beijing, China. We spend ever-increasing time indoors along with urbanization; however, the geographical distribution patterns of microbiome and antibiotic resistome, and their driving forces in household environment remains poorly characterized. Here, we surveyed the bacterial and fungal communities, and the resistome in settled dust gathered from 82 homes located across Beijing, China, employing Illumina sequencing and high-throughput quantitative PCR techniques. There was no clear geographical distribution pattern in dust-related bacterial communities although a slight but significant (P < 0.05) distance-decay relationship occurred in its community similarity; by contrast, a relatively distinct geographical clustering and a stronger distance-decay relationship were observed in fungal communities at the local scale. The cross-domain (bacteria versus fungi) relationships in the microbiome of the dust samples were mostly observed as robust co-occurrence correlations. The bacterial communities were dominated by Proteobacteria and Actinobacteria phyla, with human skin, soil and plants being potential major sources. The fungal communities largely comprised potential allergens (a median 61% of the fungal sequences), with Alternaria genus within Ascomycota phylum being the most predominant taxa. The profile of dust-related bacterial communities was mainly affected by housing factors related to occupants and houseplants, while that of fungal communities was determined by georeferenced environmental factors, particularly vascular plant diversity. Additionally, a great diversity (1.96 on average for Shannon index) and normalized abundance (2.22 copies per bacterial cell on average) of antibiotic resistance genes were detected across the dust samples, with the dominance of genes resistant to vancomycin and Macrolide-Lincosamide-Streptogramin B. The resistome profile exhibited no distinct geographical pattern, and was primarily driven by certain bacterial phyla and occupancy-related factors. Overall, we underline the significance of anthropogenic impacts and house location in structuring bacterial and fungal communities inside homes, respectively, and suggest that household dust is an overlooked reservoir for antibiotic resistance. | 2020 | 32248025 |
| 7737 | 2 | 0.9827 | Distinctive signatures of pathogenic and antibiotic resistant potentials in the hadal microbiome. BACKGROUND: Hadal zone of the deep-sea trenches accommodates microbial life under extreme energy limitations and environmental conditions, such as low temperature, high pressure, and low organic matter down to 11,000 m below sea level. However, microbial pathogenicity, resistance, and adaptation therein remain unknown. Here we used culture-independent metagenomic approaches to explore the virulence and antibiotic resistance in the hadal microbiota of the Mariana Trench. RESULTS: The results indicate that the 10,898 m Challenger Deep bottom sediment harbored prosperous microbiota with contrasting signatures of virulence factors and antibiotic resistance, compared with the neighboring but shallower 6038 m steep wall site and the more nearshore 5856 m Pacific basin site. Virulence genes including several famous large translocating virulence genes (e.g., botulinum neurotoxins, tetanus neurotoxin, and Clostridium difficile toxins) were uniquely detected in the trench bottom. However, the shallower and more nearshore site sediment had a higher abundance and richer diversity of known antibiotic resistance genes (ARGs), especially for those clinically relevant ones (e.g., fosX, sul1, and TEM-family extended-spectrum beta-lactamases), revealing resistance selection under anthropogenic stresses. Further analysis of mobilome (i.e., the collection of mobile genetic elements, MGEs) suggests horizontal gene transfer mediated by phage and integrase as the major mechanism for the evolution of Mariana Trench sediment bacteria. Notably, contig-level co-occurring and taxonomic analysis shows emerging evidence for substantial co-selection of virulence genes and ARGs in taxonomically diverse bacteria in the hadal sediment, especially for the Challenger Deep bottom where mobilized ARGs and virulence genes are favorably enriched in largely unexplored bacteria. CONCLUSIONS: This study reports the landscape of virulence factors, antibiotic resistome, and mobilome in the sediment and seawater microbiota residing hadal environment of the deepest ocean bottom on earth. Our work unravels the contrasting and unique features of virulence genes, ARGs, and MGEs in the Mariana Trench bottom, providing new insights into the eco-environmental and biological processes underlying microbial pathogenicity, resistance, and adaptative evolution in the hadal environment. | 2022 | 35468809 |
| 3479 | 3 | 0.9827 | Detecting antibiotic resistance genes and human potential pathogenic Bacteria in fishmeal by culture-independent method. Fishmeal is a fundamental ingredient of feedstuffs and is used globally in aquaculture. However, there are few data on the antibiotic resistance genes (ARGs) and human pathogenic bacteria in fishmeal and little understanding of the potential risks of fishmeal application in mariculture systems. Here, we investigated the high-throughput profiles of ARGs and human potential pathogenic bacteria (HPPB) in representative fishmeals (n = 5) and the potential impact of fishmeal on mariculture sediments. ARGs were quantified with microbial DNA quantitative PCR arrays and HPPB were analyzed with Illumina sequencing of 16S rRNA genes. The impact of the fishmeal on the aquaculture sediments was assessed in a microcosm study. Twenty-four unique ARGs (3-14 per sample) and 25 HPPB species were detected in the fishmeal samples. The most prevalent ARGs were fluoroquinolone resistance genes. The overall abundance of HPPB was 5.0-25.5%, and the HPPB species were dominated by Vibrio parahaemolyticus, Clostridium novyi, and Escherichia coli. In the mariculture microcosm sediment, fishmeal significantly increased the normalized abundance of the class I integrase gene (25.4-fold), which plays an important role in the dissemination of ARGs. Dosing with fishmeal also contributed to increases in a resident sulfanilamide resistance gene (sulI gene) and the emergence of a macrolide resistance gene (ermB gene) in the sediment. These findings demonstrated that fishmeal itself is an underestimated reservoir and source of ARGs and HPPBs, and that the application of fishmeal facilitates the dissemination of ARGs in aquaculture sediments. Our results extend our knowledge of the ARGs and HPPB within fishmeal and may provide a feasible and effective approach to the detection of ARGs and HPPB in fishmeal during food safety inspection. Graphical abstract ᅟ. | 2019 | 30707381 |
| 6378 | 4 | 0.9827 | Metagenomics reveals the divergence of gut microbiome composition and function in two common pika species (Ochotona curzoniae and Ochotona daurica) in China. Gut microbiome plays crucial roles in animal adaptation and evolution. However, research on adaptation and evolution of small wild high-altitude mammals from the perspective of gut microbiome is still limited. In this study, we compared differences in intestinal microbiota composition and function in Plateau pikas (Ochotona curzoniae) and Daurian pikas (O. daurica) using metagenomic sequencing. Our results showed that microbial community structure had distinct differences in different pika species. Prevotella, Methanosarcina, Rhizophagus, and Podoviridae were abundant bacteria, archaea, eukaryotes, and viruses in Plateau pikas, respectively. However, Prevotella, Methanosarcina, Ustilago, and Retroviridae were dominated in Daurian pikas. Functional pathways related to carbohydrate metabolism that refer to the utilization of pectin, hemicellulose, and debranching enzymes were abundant in Plateau pikas, while the function for degradation of chitin, lignin, and cellulose was more concentrated in Daurian pikas. Pika gut had abundant multidrug resistance genes, followed by glycopeptide and beta-lactamase resistance genes, as well as high-risk antibiotic resistance genes, such as mepA, tetM, and bacA. Escherichia coli and Klebsiella pneumoniae may be potential hosts of mepA. This research provided new insights for adaptation and evolution of wild animals from perspective of gut microbiome and broadened our understanding of high-risk antibiotic resistance genes and potential pathogens of wild animals. | 2024 | 39500545 |
| 3272 | 5 | 0.9826 | Metagenome-Assembled Genomes of Pig Fecal Samples in Nine European Countries: Insights into Antibiotic Resistance Genes and Viruses. Gut microbiota plays a crucial role in the health and productivity of pigs. However, the spread of antibiotic resistance genes (ARGs) and viruses within the pig intestinal microbiota poses significant threats to animal and public health. This study utilized 181 pig samples from nine European countries and employed metagenomic assembly methods to investigate the dynamics and distribution of ARGs and viruses within the pig intestinal microbiota, aiming to observing their associations with potential bacterial hosts. We identified 4605 metagenome-assembled genomes (MAGs), corresponding to 19 bacterial phyla, 97 families, 309 genera, and a total of 449 species. Additionally, 44 MAGs were classified as archaea. Analysis of ARGs revealed 276 ARG types across 21 ARG classes, with Glycopeptide being the most abundant ARG class, followed by the class of Multidrug. Treponema D sp016293915 was identified as a primary potential bacterial host for Glycopeptide. Aligning nucleotide sequences with a viral database, we identified 1044 viruses. Among the viral genome families, Peduoviridae and Intestiviridae were the most prevalent, with CAG-914 sp000437895 being the most common potential host species for both. These findings highlight the importance of MAGs in enhancing our understanding of the gut microbiome, revealing microbial diversity, antibiotic resistance, and virus-bacteria interactions. The data analysis for the article was based on the public dataset PRJEB22062 in the European Nucleotide Archive. | 2024 | 39770612 |
| 3072 | 6 | 0.9825 | Faecal microbiota and antibiotic resistance genes in migratory waterbirds with contrasting habitat use. Migratory birds may have a vital role in the spread of antimicrobial resistance across habitats and regions, but empirical data remain scarce. We investigated differences in the gut microbiome composition and the abundance of antibiotic resistance genes (ARGs) in faeces from four migratory waterbirds wintering in South-West Spain that differ in their habitat use. The white stork Ciconia ciconia and lesser black-backed gull Larus fuscus are omnivorous and opportunistic birds that use highly anthropogenic habitats such as landfills and urban areas. The greylag goose Anser anser and common crane Grus grus are herbivores and use more natural habitats. Fresh faeces from 15 individuals of each species were analysed to assess the composition of bacterial communities using 16S rRNA amplicon-targeted sequencing, and to quantify the abundance of the Class I integron integrase gene (intI1) as well as genes encoding resistance to sulfonamides (sul1), beta-lactams (bla(TEM), bla(KPC) and bla(NDM)), tetracyclines (tetW), fluoroquinolones (qnrS), and colistin (mcr-1) using qPCR. Bacterial communities in gull faeces were the richest and most diverse. Beta diversity analysis showed segregation in faecal communities between bird species, but those from storks and gulls were the most similar, these being the species that regularly feed in landfills. Potential bacterial pathogens identified in faeces differed significantly between bird species, with higher relative abundance in gulls. Faeces from birds that feed in landfills (stork and gull) contained a significantly higher abundance of ARGs (sul1, bla(TEM), and tetW). Genes conferring resistance to last resort antibiotics such as carbapenems (bla(KPC)) and colistin (mcr-1) were only observed in faeces from gulls. These results show that these bird species are reservoirs of antimicrobial resistant bacteria and suggest that waterbirds may disseminate antibiotic resistance across environments (e.g., from landfills to ricefields or water supplies), and thus constitute a risk for their further spread to wildlife and humans. | 2021 | 33872913 |
| 6387 | 7 | 0.9825 | Insights into the Evolutionary and Ecological Roles of Bathyarchaeia in Arsenic Detoxification. Arsenic (As) is a prevalent toxic element, posing significant risks to organisms, including microbes. While microbial arsenic detoxification has been extensively studied in bacteria, archaeal mechanisms remain understudied. Here, we investigated arsenic resistance genes in Bathyarchaeia, one of the most abundant archaeal lineages on Earth. Comprehensive genomic analysis of 318 Bathyarchaeia representatives revealed a widespread distribution of arsenic resistance genes, with 60% of genomes harboring genes for arsenate reduction (arsR1 and arsC2), arsenite methylation (arsM), and arsenic transport (acr3, arsP, and arsB). Phylogenetic analysis revealed that these genes are widely distributed across 14 archaeal phyla, including Asgardarchaeota, Thermoproteota, and Thermoplasmatota, with close evolutionary relationships among these archaeal lineages. In situ investigation of sediment columns and laboratory microcosm experiments demonstrated a strong positive correlation between Bathyarchaeia abundance and arsenic concentrations, suggesting their adaptation to arsenic-rich environments. Molecular dating analysis placed the emergence of Bathyarchaeia at approximately 3.01 billion years ago, with the evolution of their arsenic resistance mechanisms closely tracking major geological events, including the Great Oxidation Event (2.4-2.1 Gya), Huronian Glaciation (2.29-2.25 Gya), and Cryogenian Glaciation (∼700 Mya). Our findings highlight the critical role of Archaea in the arsenic cycle and provide insights into the evolutionary history of arsenic resistance associated with paleogeochemical changes in Bathyarchaeia. | 2025 | 40921195 |
| 7740 | 8 | 0.9825 | Diversity, functions, and antibiotic resistance genes of bacteria and fungi are examined in the bamboo plant phyllosphere that serve as food for the giant pandas. The phyllosphere of bamboo is rich in microorganisms that can disrupt the intestinal microbiota of the giant pandas that consume them, potentially leading to their death. In the present study, the abundance, diversity, biological functions (e.g., KEGG and CAZyme), and antibiotic resistance genes (ARGs) of bacteria and fungi in two bamboo species phyllosphere (Chimonobambusa szechuanensis, CS; Bashania fangiana, BF) in Daxiangling Nature Reserve (an important part of the Giant Panda National Park) were investigated respectively by amplicon sequencing of the whole 16S rRNA and ITS1-ITS2 genes on PacBio Sequel and whole-metagenome shotgun sequencing on Illumina NovaSeq 6000 platform. The results suggested that there were respectively 18 bacterial and 34 fungi biomarkers between the phyllosphere of the two species of bamboo. Beta diversity of bacteria and fungi communities exited between the two bamboos according to the (un)weighted UniFrac distance matrix. Moreover, the functional analysis showed that the largest relative abundance was found in the genes related to metabolism and global and overview maps. Glycoside hydrolases (GHs) and glycosyl transferases (GTs) have a higher abundance in two bamboo phyllospheres. Co-occurrence network modeling suggested that bacteria and fungi communities in CS phyllosphere employed a much more complex metabolic network than that in BF, and the abundance of multidrug, tetracycline, and glycopeptide resistance genes was higher and closely correlated with other ARGs. This study references the basis for protecting bamboo resources foraged by wild giant pandas and predicts the risk of antibiotic resistance in bamboo phyllosphere bacterial and fungal microbiota in the Giant Panda National Park, China. | 2025 | 39168909 |
| 7738 | 9 | 0.9825 | The microbiome and its association with antibiotic resistance genes in the hadal biosphere at the Yap Trench. The hadal biosphere, the deepest part of the ocean, is known as the least-explored aquatic environment and hosts taxonomically diverse microbial communities. However, the microbiome and its association with antibiotic resistance genes (ARGs) in the hadal ecosystem remain unknown. Here, we profiled the microbiome diversity and ARG occurrence in seawater and sediments of the Yap Trench (YT) using metagenomic sequencing. Within the prokaryote (bacteria and archaea) lineages, the main components of bacteria were Gammaproteobacteria (77.76 %), Firmicutes (8.36 %), and Alphaproteobacteria (2.25 %), whereas the major components of archaea were Nitrososphaeria (6.51 %), Nanoarchaeia (0.42 %), and Thermoplasmata (0.25 %), respectively. Taxonomy of viral contigs showed that the classified viral communities in YT seawater and sediments were dominated by Podoviridae (45.96 %), Siphoviridae (29.41 %), and Myoviridae (24.63 %). A large majority of viral contigs remained uncharacterized and exhibited endemicity. A total of 48 ARGs encoding resistance to 12 antibiotic classes were identified and their hosts were bacteria and viruses. Novel ARG subtypes mexF(YTV-1), mexF(YTV-2), mexF(YTV-3), vanR(YTV-1), vanS(YTV-1) (carried by unclassified viruses), and bacA(YTB-1) (carried by phylum Firmicutes) were detected in seawater samples. Overall, our findings imply that the hadal environment of the YT is a repository of viral and ARG diversity. | 2022 | 35870206 |
| 3116 | 10 | 0.9824 | Prediction of Antibiotic Resistance Genes in Cyanobacterial Strains by Whole Genome Sequencing. Cyanobacteria are ubiquitous in freshwater environments, but their role in aquatic resistome remains unclear. In this work, we performed whole genome sequencing on 43 cyanobacterial strains isolated from Portuguese fresh/wastewaters. From 43 available non-axenic unicyanoabacterial cultures (containing only one cyanobacterial strain and their co-occurring bacteria), it was possible to recover 41 cyanobacterial genomes from the genomic assemblies using a genome binning software, 26 of which were classified as high-quality based on completeness, contamination, N50 and contig number thresholds. By using the comprehensive antibiotic resistance database (CARD) on the assembled samples, we detected four antibiotic resistance gene (ARG) variants, conferring resistance in pathogenic bacteria to tetracyclines, fluoroquinolones (adeF-type) and macrolides (ermF-type, mefC-type and mphG-type). Among these, adeF-type was the most prevalent gene, found across 11 cyanobacterial genomes from the Nostocales order. Planktothrix presented the highest variety of close ARG matches, with hits for the macrolide resistance genes ermF-type, mefC-type and mphG-type. An analysis of the genomic assemblies also revealed an additional 12 ARGs in bacteria from the phyla Firmicutes, Proteobacteria and Bacteroidetes, present in the cyanobacterial cultures, foreseeing the horizontal gene transfer of ARGs with cyanobacteria. Additionally, more than 200 partial ARGs were detected on each recovered cyanobacterial genome, allowing for future studies of antibiotic resistance genotype/phenotype in cyanobacteria. These findings highlight the importance of further efforts to understand the role of cyanobacteria on the aquatic resistome from a One Health perspective. | 2025 | 40572139 |
| 7657 | 11 | 0.9824 | Comparison of Fecal Antimicrobial Resistance Genes in Captive and Wild Asian Elephants. The Asian elephant (Elephas maximus) is a flagship species of tropical rainforests, and it has generated much concern. In this case, the gut bacterial communities of captive and wild Asian elephants are particularly noteworthy. We aim to compare the differences in bacterial diversity and antibiotic resistance gene (ARG) subtypes in fecal samples of Asian elephants from different habitats, which may affect host health. Analyses reveal that differences in the dominant species of gut bacteria between captive and wild Asian elephants may result in significant differences in ARGs. Network analysis of bacterial communities in captive Asian elephants has identified potentially pathogenic species. Many negative correlations in network analysis suggest that different food sources may lead to differences in bacterial communities and ARGs. Results also indicate that the ARG levels in local captive breeding of Asian elephants are close to those of the wild type. However, we found that local captive elephants carry fewer ARG types than their wild counterparts. This study reveals the profile and relationship between bacterial communities and ARGs in different sources of Asian elephant feces, providing primary data for captive breeding and rescuing wild Asian elephants. | 2023 | 37237762 |
| 3247 | 12 | 0.9824 | Metagenome-wide characterization of shared antimicrobial resistance genes in sympatric people and lemurs in rural Madagascar. BACKGROUND: Tracking the spread of antibiotic resistant bacteria is critical to reduce global morbidity and mortality associated with human and animal infections. There is a need to understand the role that wild animals in maintenance and transfer of antibiotic resistance genes (ARGs). METHODS: This study used metagenomics to identify and compare the abundance of bacterial species and ARGs detected in the gut microbiomes from sympatric humans and wild mouse lemurs in a forest-dominated, roadless region of Madagascar near Ranomafana National Park. We examined the contribution of human geographic location toward differences in ARG abundance and compared the genomic similarity of ARGs between host source microbiomes. RESULTS: Alpha and beta diversity of species and ARGs between host sources were distinct but maintained a similar number of detectable ARG alleles. Humans were differentially more abundant for four distinct tetracycline resistance-associated genes compared to lemurs. There was no significant difference in human ARG diversity from different locations. Human and lemur microbiomes shared 14 distinct ARGs with highly conserved in nucleotide identity. Synteny of ARG-associated assemblies revealed a distinct multidrug-resistant gene cassette carrying dfrA1 and aadA1 present in human and lemur microbiomes without evidence of geographic overlap, suggesting that these resistance genes could be widespread in this ecosystem. Further investigation into intermediary processes that maintain drug-resistant bacteria in wildlife settings is needed. | 2024 | 39099658 |
| 9861 | 13 | 0.9824 | Comparative genomics of native plasmids from plant pathogenic Gammaproteobacteria. Plasmids are key in the evolution and adaptation of plant pathogenic Gammaproteobacteria (PPG), yet their diversity and functional contributions remain underexplored. Here, comparative genomics revealed extensive variation in plasmid size, replicon types, mobility, and genetic content across PPG. Most plasmids are small (< 200 kb), except in Pantoea, exhibiting high coding densities (76% to 78%). Five ancestral replicon types were identified across multiple orders, indicating vertical descent yet efficient horizontal transfer across taxa, although with limited genetic conservation. Virulence plasmids are widespread (56% to 68%) but differ in virulence gene content across orders: type III effector (T3E) genes are common in Pseudomonas and Xanthomonas, but rare in Enterobacterales and Xylella, aligning with their smaller effector repertoires. Plasmids frequently carry regulatory genes, highlighting their role in bacterial phenotype modulation. Distinct patterns were observed among orders: Enterobacterales plasmids often harbor thiamin biosynthesis operons and transcriptional regulators but lack post-transcriptional regulators, while most Pseudomonas and Xanthomonas plasmids are mobile, enriched in T3E genes, and exhibit high insertion sequence densities, fostering DNA mobility. Resistance to ultraviolet light is common, but not to antimicrobial compounds. These findings highlight the dynamic role of plasmids in spreading adaptive traits, shaping virulence, and driving the evolution of plant pathogenic bacteria. | 2025 | 40273218 |
| 7646 | 14 | 0.9824 | Assessment of Bacterial Community and Other Microorganism Along the Lam Takhong Watercourse, Nakhon Ratchasima, Thailand. Lam Takhong, a vital watercourse in Nakhon Ratchasima province, Thailand, supports agricultural, recreational, and urban activities. Originating in a national park, it flows through urban areas before discharging into a dam and running off via the sluice gate. While water quality monitoring is routine, microbial community data have never been reported. This study assesses the microorganism diversity and functional genes in Lam Takhong watercourse using a shotgun sequencing metagenomics approach. Water samples were collected from the upstream, midstream, and downstream sections. The midstream area exhibited the highest abundance of fecal coliform bacteria, plankton, and benthos, suggesting elevated pollution levels. Genes related to metabolism, particularly carbohydrate and amino acid pathways, were predominant. Proteobacteria was the most abundant phylum found in the water, with Limnohabitans as the dominant planktonic bacteria. Bacteria such as Staphylococcus, Mycobacterium, Escherichia, Pseudomonas, Enterococcus, Neisseria, Streptomyces, and Salmonella were detected, along with antibiotic resistance genes, raising public health concerns. These findings emphasize the need for microbial monitoring in the Lam Takhong to determine the potential water quality bioindicator and prevent potential disease spread through the water system. | 2025 | 40244481 |
| 3115 | 15 | 0.9824 | Characterisation of the gut microbiome and surveillance of antibiotic resistance genes in green sea turtles (Chelonia mydas). Green sea turtles (Chelonia mydas) are globally endangered marine herbivores that maintain the health of seagrass and coastal ecosystems. Their populations are declining due to human activities, including environmental pollution, which can disrupt gut microbial communities and compromise nutrition, immunity, and overall health. In this study, cloacal swabs from 139 green sea turtles categorised as captive juveniles, captive adults and wild stranded animals in the Gulf of Thailand, were analysed via shotgun metagenomic sequencing to elucidate bacterial taxonomic diversity and ARG profiles. In captive juveniles, Pseudomonadota was the most abundant phylum, followed by Ascomycota and Basidiomycota. In captive adults, Pseudomonadota exhibited an even greater predominance, with only minor contributions from unclassified bacteria and other taxa. In wild stranded green sea turtles, Pseudomonadota was dominant in their gut microbiome, but this was accompanied by notable levels of Actinomycetota, Bacteroidota, and Bacillota. Stranded turtles exhibited highest microbial diversity and variability, while captive adult turtles showed the lowest. Resistome profiling also revealed significant differences in the relative abundance of antibiotic resistance genes across all three groups. MacB (macrolide resistance) was the most abundant gene overall, with the highest abundance observed in juveniles (4.8 %). Stranded turtles exhibited elevated levels of TetA(58) (tetracycline resistance, 2.6 %) and msbA (nitroimidazole resistance, 2.2 %), while adults showed the greatest enrichment of Ecol_fabG_TRC (triclosan resistance, 3.8 %) and TxR (tetracycline resistance, 3.6 %). These data demonstrate that marked variability existed in the gut microbiome and resistome of green sea turtles across different life stages in captive or wild environments. This offers critical insights for the development of targeted conservation strategies and health management practices for both wild and captive green sea turtles. Strategies to mitigate the spread of antibiotic resistance should be developed. | 2025 | 41075532 |
| 3248 | 16 | 0.9823 | Geographical resistome profiling in the honeybee microbiome reveals resistance gene transfer conferred by mobilizable plasmids. BACKGROUND: The spread of antibiotic resistance genes (ARGs) has been of global concern as one of the greatest environmental threats. The gut microbiome of animals has been found to be a large reservoir of ARGs, which is also an indicator of the environmental antibiotic spectrum. The conserved microbiota makes the honeybee a tractable and confined ecosystem for studying the maintenance and transfer of ARGs across gut bacteria. Although it has been found that honeybee gut bacteria harbor diverse sets of ARGs, the influences of environmental variables and the mechanism driving their distribution remain unclear. RESULTS: We characterized the gut resistome of two closely related honeybee species, Apis cerana and Apis mellifera, domesticated in 14 geographic locations across China. The composition of the ARGs was more associated with host species rather than with geographical distribution, and A. mellifera had a higher content of ARGs in the gut. There was a moderate geographic pattern of resistome distribution, and several core ARG groups were found to be prevalent among A. cerana samples. These shared genes were mainly carried by the honeybee-specific gut members Gilliamella and Snodgrassella. Transferrable ARGs were frequently detected in honeybee guts, and the load was much higher in A. mellifera samples. Genomic loci of the bee gut symbionts containing a streptomycin resistance gene cluster were nearly identical to those of the broad-host-range IncQ plasmid, a proficient DNA delivery system in the environment. By in vitro conjugation experiments, we confirmed that the mobilizable plasmids could be transferred between honeybee gut symbionts by conjugation. Moreover, "satellite plasmids" with fragmented genes were identified in the integrated regions of different symbionts from multiple areas. CONCLUSIONS: Our study illustrates that the gut microbiota of different honeybee hosts varied in their antibiotic resistance structure, highlighting the role of the bee microbiome as a potential bioindicator and disseminator of antibiotic resistance. The difference in domestication history is highly influential in the structuring of the bee gut resistome. Notably, the evolution of plasmid-mediated antibiotic resistance is likely to promote the probability of its persistence and dissemination. Video Abstract. | 2022 | 35501925 |
| 7658 | 17 | 0.9823 | Metagenomic and Antibiotic Resistance Analysis of the Gut Microbiota in Larus relictus and Anatidae Species Inhabiting the Honghaizi Wetland of Ordos, Inner Mongolia, from 2021 to 2023. Gut microbes thrive by utilising host energy and, in return, provide valuable benefits, akin to a symbiotic relationship. Here, metagenomic sequencing was performed to characterise and compare the community composition, diversity and antibiotic resistance of the gut microbiota of Relict gull (Larus relictus) and Anatidae species. Alpha diversity analysis revealed that the intestinal microbial richness of L. relictus was significantly lower than that of Anatidae, with distinct differences observed in microbial composition. Notably, the intestines of L. relictus harboured more pathogenic bacteria such as clostridium, which may contribute to the decline in their population and endangered status. A total of 117 strains of Escherichia coli were isolated, with 90.60% exhibiting full susceptibility to 21 antibiotics, while 25.3% exhibited significant biofilm formation. Comprehensive Antibiotic Resistance Database data indicated that glycopeptide resistance genes were the most prevalent type carried by migratory birds, alongside quinolone, tetracycline and lincosamide resistance genes. The abundance of resistance genes carried by migratory birds decreased over time. This metagenomic analysis provides valuable insights into the intestinal microbial composition of these wild bird species, offering important guidance for their conservation efforts, particularly for L. relictus, and contributing to our understanding of pathogen spread and antibiotic-resistant bacteria. | 2024 | 38792807 |
| 6804 | 18 | 0.9823 | Seasonal variations of profiles of antibiotic resistance genes and virulence factor genes in household dust from Beijing, China revealed by the metagenomics. Household-related microbiome is closely related with human health. However, the knowledge about profiles of antibiotic resistance genes (ARGs) and virulence factor genes (VFGs) which are carried by microbes inside homes and their temporal dynamics are rather limited. Here we monitored the seasonal changes of bacterial community (especially pathogenic bacteria), ARGs, and VFGs in household dust samples during two years. Based on metagenomic sequencing, the dust-related bacterial pathogenic community, ARGs, and VFGs all harbored the lowest richness in spring among four seasons. Their structure (except that of VFGs) also exhibited remarkable differences among the seasons. The structural variations of ARGs and VFGs were almost explained by mobile genetic elements (MGEs), bacterial pathogens, and particulate matter-related factors, with MGEs explaining the most. Moreover, the total normalized abundance of ARGs or VFGs showed no significant change across the seasons. Results of metagenomic binning and microbial network both showed that several pathogenic taxa (e.g., Ralstonia pickettii) were strongly linked with numerous ARGs (mainly resistant to multidrug) and VFGs (mainly encoding motility) simultaneously. Overall, these findings underline the significance of MGEs in structuring ARGs and VFGs inside homes along with seasonal variations, suggesting that household dust is a neglected reservoir for ARGs and VFGs. | 2024 | 38636860 |
| 3778 | 19 | 0.9823 | ggMOB: Elucidation of genomic conjugative features and associated cargo genes across bacterial genera using genus-genus mobilization networks. Horizontal gene transfer mediated by conjugation is considered an important evolutionary mechanism of bacteria. It allows organisms to quickly evolve new phenotypic properties including antimicrobial resistance (AMR) and virulence. The frequency of conjugation-mediated cargo gene exchange has not yet been comprehensively studied within and between bacterial taxa. We developed a frequency-based network of genus-genus conjugation features and candidate cargo genes from whole-genome sequence data of over 180,000 bacterial genomes, representing 1,345 genera. Using our method, which we refer to as ggMOB, we revealed that over half of the bacterial genomes contained one or more known conjugation features that matched exactly to at least one other genome. Moreover, the proportion of genomes containing these conjugation features varied substantially by genus and conjugation feature. These results and the genus-level network structure can be viewed interactively in the ggMOB interface, which allows for user-defined filtering of conjugation features and candidate cargo genes. Using the network data, we observed that the ratio of AMR gene representation in conjugative versus non-conjugative genomes exceeded 5:1, confirming that conjugation is a critical force for AMR spread across genera. Finally, we demonstrated that clustering genomes by conjugation profile sometimes correlated well with classical phylogenetic structuring; but that in some cases the clustering was highly discordant, suggesting that the importance of the accessory genome in driving bacterial evolution may be highly variable across both time and taxonomy. These results can advance scientific understanding of bacterial evolution, and can be used as a starting point for probing genus-genus gene exchange within complex microbial communities that include unculturable bacteria. ggMOB is publicly available under the GNU licence at https://ruiz-hci-lab.github.io/ggMOB/. | 2022 | 36568361 |