Oxford Nanopore long reads of simulated bacterial communities from fresh spinach and surface water were generated (R9.4.1+SQK-LSK109 and R10.4+SQK-LSK112; 0.5, one, and two million reads). Salmonella enterica serotype Heidelberg, Montevideo, or Typhimurium was included alone or in combination in the spinach community, while the water community harbored Pseudomonas aeruginosa.

Hypersaline environments are extreme habitats with a limited prokaryotic diversity, mainly restricted to halophilic or halotolerant archaeal and bacterial taxa adapted to highly saline conditions. This study attempts to analyze the taxonomic and functional diversity of the prokaryotes that inhabit a solar saltern located at the Atlantic Coast, in Isla Cristina (Huelva, Southwest Spain), and the influence of salinity on the diversity and metabolic potential of these prokaryotic communities, as well as the interactions and cooperation among the individuals within that community. Brine samples were obtained from different saltern ponds, with a salinity range between 19.5 % and 39 % (w/v). Total prokaryotic DNA was sequenced using the Illumina shotgun metagenomic strategy and the raw sequence data were analyzed using supercomputing services following the MetaWRAP and SqueezeMeta protocols. The most abundant phyla at moderate salinities (19.5-22 % [w/v]) were Methanobacteriota (formerly \"Euryarchaeota\"), Pseudomonadota and Bacteroidota, followed by Balneolota and Actinomycetota and Uroviricota in smaller proportions, while at high salinities (36-39 % [w/v]) the most abundant phylum was Methanobacteriota, followed by Bacteroidota. The most abundant genera at intermediate salinities were Halorubrum and the bacterial genus Spiribacter, while the haloarchaeal genera Halorubrum, Halonotius, and Haloquadratum were the main representatives at high salinities. A total of 65 MAGs were reconstructed from the metagenomic datasets and different functions and pathways were identified in them, allowing to find key taxa in the prokaryotic community able to synthesize and supply essential compounds, such as biotin, and precursors of other bioactive molecules, like β-carotene, and bacterioruberin, to other dwellers in this habitat, lacking the required enzymatic machinery to produce them. This work shed light on the ecology of aquatic hypersaline environments, such as the Atlantic Coast salterns, and on the dynamics and factors affecting the microbial populations under such extreme conditions.

The key association between gut dysbiosis and cancer is already known. Here, we used whole-genome shotgun sequencing (WGS) and gas chromatography/mass spectrometry (GC/MS) to conduct metagenomic and metabolomic analyses to identify common and distinct taxonomic configurations among 40, 45, 71, 34, 50, 60, and 40 patients with colorectal cancer, stomach cancer, breast cancer, lung cancer, melanoma, lymphoid neoplasms and acute myeloid leukemia (AML), respectively, and compared the data with those from sex- and age-matched healthy controls (HC). α-diversity differed only between the lymphoid neoplasm and AML groups and their respective HC, while β-diversity differed between all groups and their HC. Of 203 unique species, 179 and 24 were under- and over-represented, respectively, in the case groups compared with HC. Of these, Faecalibacillus intestinalis was under-represented in each of the seven groups studied, Anaerostipes hadrus was under-represented in all but the stomach cancer group, and 22 species were under-represented in the remaining five case groups. There was a marked reduction in the gut microbiome cancer index in all case groups except the AML group. Of the short-chain fatty acids and amino acids tested, the relative concentration of formic acid was significantly higher in each of the case groups than in HC, and the abundance of seven species of Faecalibacterium correlated negatively with most amino acids and formic acid, and positively with the levels of acetic, propanoic, and butanoic acid. We found more differences than similarities between the studied malignancy groups, with large variations in diversity, taxonomic/metabolomic profiles, and functional assignments. While the results obtained may demonstrate trends rather than objective differences that correlate with different types of malignancy, the newly developed gut microbiota cancer index did distinguish most of the cancer cases from HC. We believe that these data are a promising step forward in the search for new diagnostic and predictive tests to assess intestinal dysbiosis among cancer patients.

Infectious endophthalmitis is a severe ophthalmic emergency. This infection can be caused by bacteria and fungi. For efficient treatment, the administration of antimicrobial drugs to which the microbes are susceptible is essential. The aim of this study was to identify micro-organisms in biopsies of Mexican endophthalmitis patients using metagenomic next-generation sequencing and determine which antibiotic resistance genes were present in the biopsy samples. In this prospective case study, 19 endophthalmitis patients were recruited. Samples of vitreous or aqueous humour were extracted for DNA extraction for metagenomic next-generation sequencing. Analysis of the sequencing results revealed the presence of a wide variety of bacteria in the biopsies. Resistome analysis showed that homologues of antibiotic resistance genes were present in several biopsy samples. Genes possibly conferring resistance to ceftazidime and vancomycin were detected in addition to various genes encoding efflux pumps. Our findings contrast with the widespread opinion that only one or a few bacterial strains are present in the infected tissues of endophthalmitis patients. These diverse communities might host many of the resistance genes that were detected, which can further complicate the infections.

After Amazonia, the Congo Basin represents the second-largest tropical rainforest area in the world. This basin harbours remarkable biodiversity, yet much of its microbiological diversity within its waters, soils, and populations remains largely unexplored and undiscovered. While many initiatives to characterize global biodiversity are being undertaken, few are conducted in Africa and none of them concern the Congo Basin specifically in urban areas. In this context, we assessed the microbial diversity present in gutter water in the city of Pointe-Noire, Congo. This town has interesting characteristics as the population density is high and it is located between the Atlantic Ocean and the forest of Mayombe in Central Africa. The findings illuminate the microbial composition of surface water in Pointe-Noire. The dataset allows the identification of putative new bacteria through the assembly of 81 meta-genome-assembled genomes. It also serves as a valuable primary resource for assessing the presence of antibiotic-resistant genes, offering a useful tool for monitoring risks by public health authorities.

BACKGROUND: As a nexus of routine antibiotic use and zoonotic pathogen presence, the livestock farming environment is a potential hotspot for the emergence of zoonotic diseases and antibiotic resistant bacteria. Livestock can further facilitate disease transmission by serving as intermediary hosts for pathogens before a spillover event. In light of this, we aimed to characterize the microbiomes and resistomes of dairy workers, whose exposure to the livestock farming environment places them at risk for facilitating community transmission of antibiotic resistant genes and emerging zoonotic diseases.
RESULTS: Using shotgun sequencing, we investigated differences in the taxonomy, diversity and gene presence of 10 dairy farm workers and 6 community controls\' gut metagenomes, contextualizing these samples with additional publicly available gut metagenomes. We found no significant differences in the prevalence of resistance genes, virulence factors, or taxonomic composition between the two groups. The lack of statistical significance may be attributed, in part, to the limited sample size of our study or the potential similarities in exposures between the dairy workers and community controls. We did, however, observe patterns warranting further investigation including greater abundance of tetracycline resistance genes and prevalence of cephamycin resistance genes as well as lower average gene diversity (even after accounting for differential sequencing depth) in dairy workers\' metagenomes. We also found evidence of commensal organism association with tetracycline resistance genes in both groups (including Faecalibacterium prausnitzii, Ligilactobacillus animalis, and Simiaoa sunii).
CONCLUSIONS: This study highlights the utility of shotgun metagenomics in examining the microbiomes and resistomes of livestock workers, focusing on a cohort of dairy workers in the United States. While our study revealed no statistically significant differences between groups in taxonomy, diversity and gene presence, we observed patterns in antibiotic resistance gene abundance and prevalence that align with findings from previous studies of livestock workers in China and Europe. Our results lay the groundwork for future research involving larger cohorts of dairy and non-dairy workers to better understand the impact of occupational exposure to livestock farming on the microbiomes and resistomes of workers.

Soybean cultivation in tropical regions relies on symbioses with nitrogen-fixing Bradyrhizobium and plant growth-promoting bacteria (PGPBs), reducing environmental impacts of N fertilizers and pesticides. We evaluate the effects of soybean inoculation with different bacterial consortia combined with PGPBs or microbial secondary metabolites (MSMs) on rhizosoil chemistry, plant physiology, plant nutrition, grain yield, and rhizosphere microbial functions under field conditions over three growing seasons with four treatments: standard inoculation of Bradyrhizobium japonicum and Bradyrhizobium diazoefficiens consortium (SI); SI plus foliar spraying with Bacillus subtilis (SI + Bs); SI plus foliar spraying with Azospirillum brasilense (SI + Az); and SI plus seed application of MSMs enriched in lipo-chitooligosaccharides extracted from B. diazoefficiens and Rhizobium tropici (SI + MSM). Rhizosphere microbial composition, diversity, and function was assessed by metagenomics. The relationships between rhizosoil chemistry, plant nutrition, grain yield, and the abundance of microbial taxa and functions were determined by generalized joint attribute modeling. The bacterial consortia had the most significant impact on rhizosphere soil fertility, which in turn affected the bacterial community, plant physiology, nutrient availability, and production. Cluster analysis identified microbial groups and functions correlated with shifts in rhizosoil chemistry and plant nutrition. Bacterial consortia positively modulated specific genera and functional pathways involved in biosynthesis of plant secondary metabolites, amino acids, lipopolysaccharides, photosynthesis, bacterial secretion systems, and sulfur metabolism. The effects of the bacterial consortia on the soybean holobiont, particularly the rhizomicrobiome and rhizosoil fertility, highlight the importance of selecting appropriate consortia for desired outcomes. These findings have implications for microbial-based agricultural practices that enhance crop productivity, quality, and sustainability.

Antibiotic resistance is a worldwide problem that imposes a devastating effect on developing countries and requires immediate interventions. Initially, most of the antibiotic drugs were identified by culturing soil microbes. However, this method is prone to discovering the same antibiotics repeatedly. The present study employed a shotgun metagenomics approach to investigate the taxonomic diversity, functional potential, and biosynthetic capacity of microbiomes from two natural agricultural farmlands located in Bekeka and Welmera Choke Kebelle in Ethiopia for the first time. Analysis of the small subunit rRNA revealed bacterial domain accounting for 83.33% and 87.24% in the two selected natural farmlands. Additionally, the analysis showed the dominance of Proteobacteria representing 27.27% and 28.79% followed by Actinobacteria making up 12.73% and 13.64% of the phyla composition. Furthermore, the analysis revealed the presence of unassigned bacteria in the studied samples. The metagenome functional analysis showed 176,961 and 104, 636 number of protein-coding sequences (pCDS) from the two samples found a match with 172,655 and 102, 275 numbers of InterPro entries, respectively. The Genome ontology annotation suggests the presence of 5517 and 3293 pCDS assigned to the \"biosynthesis process\". Numerous Kyoto Encyclopedia of Genes and Genomes modules (KEGG modules) involved in the biosynthesis of terpenoids and polyketides were identified. Furthermore, both known and novel Biosynthetic gene clusters, responsible for the production of secondary metabolites, such as polyketide synthases, non-ribosomal peptide synthetase, ribosomally synthesized and post-translationally modified peptides (Ripp), and Terpene, were discovered. Generally, from the results it can be concluded that the microbiomes in the selected sampling sites have a hidden functional potential for the biosynthesis of secondary metabolites. Overall, this study can serve as a strong preliminary step in the long journey of bringing new antibiotics to the market.

Arid regions harbor seasonal and permanent wetlands, as biodiversity hotspots crucial for ecosystem services despite harsh conditions. These wetlands, typically dependent on episodic intense rainfall, are understudied compared to their humid counterparts. While the diversity of plants and animals in these wetlands is well-known, the microbial communities remain largely unexplored. To address this knowledge gap, we employed metagenome sequencing technologies to profile protist communities, including pathogenic protozoa, and their associated functional pathways, in sediment of permanent and seasonal arid freshwater wetlands across northern South Africa. Results revealed a core community of protists dominated by phylum Apicomplexa (66.73 %), Euglenazoa (19.03 %), Bacillariophyta (5.44 %), Metamonada (4.65 %), Cryptophyta (1.90 %), and Amoebazoa (1.21 %). Seasonal wetlands showed significantly higher protist diversity compared to permanent wetlands (Shannon index, p = 0.019; Chao1, p = 0.0095). A high abundance and diversity of human and zoonotic pathogenic protists (87.67 %) was observed, with lower levels of photoautotrophs (6.69 %) and limited diversity of phagotrophs (5.64 %). Key photoautotrophs identified included diatoms (Thalassiosiraceae and Phaeodactylaceae) and cryptophytes (genus Hemiselmis and Cryptophyta), with consumers/phagotrophs exhibited a correlation with the bacterial community abundance (r2 = 0.218, p < 0.001). Pathogenic protozoans identified, include malaria-causing Plasmodium, kinetoplastids (genus Besnoita, Theilleria, Neospora, Toxoplasma, Encephalitozoon, and Babesia) and waterborne protozoans of public health importance (such as Cryptosporidium parvum and Giardia lamblia). Furthermore, the enrichment of pathogenesis-associated pathways (amino acid biosynthesis, peptidoglycan maturation, heme biosynthesis and degradation, and the Calvin-Benson-Bassham cycle), along with virulence gene families identified, highlighted these wetlands as potential reservoirs for infectious diseases. Our results unveil a baseline protist taxonomic and functional composition within arid wetlands, including beneficial and pathogenic protozoa. The close proximity of these wetlands to human activity raises concern for local and transboundary spread of these pathogens. Thus, continued monitoring is vital for disease control and preserving these unique ecosystems.

BACKGROUND: Respiratory viruses significantly impact global morbidity and mortality, causing more disease in humans than any other infectious agent. Beyond pathogens, various viruses and bacteria colonize the respiratory tract without causing disease, potentially influencing respiratory diseases\' pathogenesis. Nevertheless, our understanding of respiratory microbiota is limited by technical constraints, predominantly focusing on bacteria and neglecting crucial populations like viruses. Despite recent efforts to improve our understanding of viral diversity in the human body, our knowledge of viral diversity associated with the human respiratory tract remains limited.
METHODS: Following a comprehensive search in bibliographic and sequencing data repositories using keyword terms, we retrieved shotgun metagenomic data from public repositories (n = 85). After manual curation, sequencing data files from 43 studies were analyzed using EVEREST (pipEline for Viral assEmbly and chaRactEriSaTion). Complete and high-quality contigs were further assessed for genomic and taxonomic characterization.
RESULTS: Viral contigs were obtained from 194 out of the 868 FASTQ files processed through EVEREST. Of the 1842 contigs that were quality assessed, 8% (n = 146) were classified as complete/high-quality genomes. Most of the identified viral contigs were taxonomically classified as bacteriophages, with taxonomic resolution ranging from the superkingdom level down to the species level. Captured contigs were spread across 25 putative families and varied between RNA and DNA viruses, including previously uncharacterized viral genomes. Of note, airway samples also contained virus(es) characteristic of the human gastrointestinal tract, which have not been previously described as part of the lung virome. Additionally, by performing a meta-analysis of the integrated datasets, ecological trends within viral populations linked to human disease states and their biogeographical distribution along the respiratory tract were observed.
CONCLUSIONS: By leveraging publicly available repositories of shotgun metagenomic data, the present study provides new insights into viral genomes associated with specimens from the human respiratory tract across different disease spectra. Further studies are required to validate our findings and evaluate the potential impact of these viral communities on respiratory tract physiology.