Biocontrol capacity of bacteria isolated from sawdust of the dairy cattle production environment.

This research paper aimed to find endemic bacteria from the cattle production system to control the growth of mastitis pathogens. Bacteria were isolated from compost barn sawdust of two dairy cattle systems and later tested to verify their ability to control the growth of Staphylococcus aureus isolates obtained from cattle with mastitis. Bacterial isolates from these systems were tested to verify biocontrol capacity using the double-layer method. A total of 189 isolates were obtained from all samples by considering the morphology of the different bacterial colonies, with 30 isolates showing positive results for the growth control of at least one S. aureus strain and 19 isolates showing the ability to control more than one pathogen strain. The ability to control more than one pathogen and present a significant halo of inhibition in our isolates represents positive traits in the search for cattle mastitis biocontrol microorganisms. Thus, the results obtained represent the range of bacteria capable of controlling the pathogens without the use of antibiotics.

Methotrexate and Non-Surgical Periodontal Treatment Change the Oral-Gut Microbiota in Rheumatoid Arthritis: A Prospective Cohort Study.

This study evaluated the changes in the composition of oral-gut microbiota in patients with rheumatoid arthritis (RA) caused by methotrexate (MTX) and non-surgical periodontal treatment (NSPT). Assessments were performed at baseline (T0), 6 months after MTX treatment (T1), and 45 days after NSPT (T2). The composition of the oral and gut microbiota was assessed by amplifying the V4 region of the 16S gene from subgingival plaques and stools. The results of the analysis of continuous variables were presented descriptively and non-parametric tests and Spearman's correlation were adopted. A total of 37 patients (27 with periodontitis) were evaluated at T0; 32 patients (24 with periodontitis) at T1; and 28 patients (17 with periodontitis) at T2. MTX tended to reduce the alpha diversity of the oral-gut microbiota, while NSPT appeared to increase the number of different species of oral microbiota. MTX and NSPT influenced beta diversity in the oral microbiota. The relative abundance of oral microbiota was directly influenced by periodontal status. MTX did not affect the periodontal condition but modified the correlations that varied from weak to moderate (p < 0.05) between clinical parameters and the microbiota. MTX and NSPT directly affected the composition and richness of the oral-gut microbiota. However, MTX did not influence periodontal parameters.

Methotrexate promotes recovery of arthritis-induced alveolar bone loss and modifies the composition of the oral-gut microbiota.

OBJECTIVES: The impact of rheumatoid arthritis (RA) on the shaping of the oral and gut microbiome raises the question of whether and how RA treatment modifies microbial communities. We examined changes in the oral and gut microbiota in a mouse model of antigen-induced arthritis (AIA) treated or not with methotrexate (MTX). METHODS: Maxillae and stools were evaluated by the MiSeq platform of the V4 region of the 16S rRNA gene. Alveolar bone parameters were analysed by micro-computed tomography. Moreover, arthritis-induced changes in hyperalgesia and oedema were assessed, along with the impact on periodontal bone health. RESULTS: Microbial communities in MTX-treated AIA mice revealed distinct clusters compared to the control and AIA groups. Overall, MTX impacted the richness and variability of microorganisms in the oral-gut axis microbiome at the phylum level. Regarding the oral microbiome, while in the control group the most dominant phylum was Firmicutes, in the AIA group there was a shift towards the predominance of Campilobacteriota and Bacteroidetes associated with the disease. MTX treatment led to greater dominance of the health-associated phylum Proteobacteria. In the gut microbiome, AIA induction resulted in increased abundance of the Verrucomicrobiota phylum, and MTX treatment restored its levels compared to control. Importantly, the MTX-treated AIA animals had significantly less periodontal bone loss, as well as decreased hyperalgesia and joint oedema compared to the AIA animals. CONCLUSION: Data suggest the benefit of MTX treatment in protecting alveolar bone, in addition to providing new insights on the drug-microbiome interaction in the course of RA.

A watershed impacted by anthropogenic activities: Microbial community alterations and reservoir of antimicrobial resistance genes.

Water is the main resource for maintaining life. Anthropic activities influence the microbial epidemiological chain in watersheds, which can act as ways of disseminating microorganisms resistant to antimicrobial drugs, with impacts on human, animal, and environmental health. Here, we characterized aquatic microbial communities and their resistomes in samples collected along Rio das Ostras watershed during two seasons. Surface water samples were collected at eleven sites from the Jundiá, Iriry, and Rio das Ostras rivers in two seasons (dry and wet season). Microbial DNA was extracted, high-throughput sequenced and screened for antimicrobial resistance genetic (ARG) markers. The physicochemical characteristics and the microbiota data confirmed that Rio das Ostras watershed can be divided into three well defined portions: rural, urban, and marine. Rural areas were enriched by bacteria typically found in limnic environments and Patescibacteria phyla. The urban portion was characterized by sites with low pH and groups associated with iron oxidation. Some genera of clinical relevance were also identified, though in relatively low abundance. The marine site was enriched mainly by Cyanobacteria and bacteria that showed strong correlation with conductivity, salinity, and chloride. Twenty-six ARG markers were identified on the resistome, being found most frequently in the urban area, despite being present in rural sites. Among them were some related to classes of great clinical concern, such as genes coding for extended-spectrum beta-lactamase (blaCTX-M and blaTEM), resistance to carbapenems (blaKPC) and to methicillin by Staphylococcus aureus (mecA). These results broaden our understanding of the microbial community of a watershed impacted by anthropogenic actions. The large number of ARGs detected along the Rio das Ostras watershed contrasts with the small number of microorganisms of clinical relevance observed, suggesting that antimicrobial resistance has arisen from non-clinical environments and microbes. Our results corroborate that freshwater acts as a reservoir of antimicrobial resistance genes.

Metataxonomic analyses reveal differences in aquifer bacterial community as a function of creosote contamination and its potential for contaminant remediation.

Metataxonomic approach was used to describe the bacterial community from a creosote-contaminated aquifer and to access the potential for in situ bioremediation of the polycyclic aromatic hydrocarbons (PAHs) by biostimulation. In general, the wells with higher PAH contamination had lower richness and diversity than others, using the Shannon and Simpson indices. By the principal coordinate analysis (PCoA) it was possible to observe the clustering of the bacterial community of most wells in response of the presence of PAH contamination. The significance analysis using edgeR package of the R program showed variation in the abundance of some Operational Taxonomic Units (OTUs) of contaminated wells compared to uncontaminated ones. Taxons enriched in the contaminated wells were correlated positively (p < 0.05) with the hydrocarbons, according to redundancy analysis (RDA). All these enriched taxa have been characterized as PAH degrading agents, such as the genus Comamonas, Geobacter, Hydrocarboniphaga, Anaerolinea and Desulfomonile. Additionally, it was possible to predict, with the PICRUSt program, a greater proportion of pathways and genes related to the degradation of PAHs in the wells with higher contamination levels. We conclude that the contaminants promoted the enrichment of several groups of degrading bacteria in the area, which strengthens the feasibility of applying biostimulation as an aquifer remediation strategy.

Comparative metagenome of a stream impacted by the urbanization phenomenon

Abstract Rivers and streams are important reservoirs of freshwater for human consumption. These ecosystems are threatened by increasing urbanization, because raw sewage discharged into them alters their nutrient content and may affect the composition of their microbial community. In the present study, we investigate the taxonomic and functional profile of the microbial community in an urban lotic environment. Samples of running water were collected at two points in the São Pedro stream: an upstream preserved and non-urbanized area, and a polluted urbanized area with discharged sewage. The metagenomic DNA was sequenced by pyrosequencing. Differences were observed in the community composition at the two sites. The non-urbanized area was overrepresented by genera of ubiquitous microbes that act in the maintenance of environments. In contrast, the urbanized metagenome was rich in genera pathogenic to humans. The functional profile indicated that the microbes act on the metabolism of methane, nitrogen and sulfur, especially in the urbanized area. It was also found that virulence/defense (antibiotic resistance and metal resistance) and stress response-related genes were disseminated in the urbanized environment. The structure of the microbial community was altered by uncontrolled anthropic interference, highlighting the selective pressure imposed by high loads of urban sewage discharged into freshwater environments.

Comparative metagenome of a stream impacted by the urbanization phenomenon.

Rivers and streams are important reservoirs of freshwater for human consumption. These ecosystems are threatened by increasing urbanization, because raw sewage discharged into them alters their nutrient content and may affect the composition of their microbial community. In the present study, we investigate the taxonomic and functional profile of the microbial community in an urban lotic environment. Samples of running water were collected at two points in the São Pedro stream: an upstream preserved and non-urbanized area, and a polluted urbanized area with discharged sewage. The metagenomic DNA was sequenced by pyrosequencing. Differences were observed in the community composition at the two sites. The non-urbanized area was overrepresented by genera of ubiquitous microbes that act in the maintenance of environments. In contrast, the urbanized metagenome was rich in genera pathogenic to humans. The functional profile indicated that the microbes act on the metabolism of methane, nitrogen and sulfur, especially in the urbanized area. It was also found that virulence/defense (antibiotic resistance and metal resistance) and stress response-related genes were disseminated in the urbanized environment. The structure of the microbial community was altered by uncontrolled anthropic interference, highlighting the selective pressure imposed by high loads of urban sewage discharged into freshwater environments.

ZIKV - CDB: A Collaborative Database to Guide Research Linking SncRNAs and ZIKA Virus Disease Symptoms.

BACKGROUND: In early 2015, a ZIKA Virus (ZIKV) infection outbreak was recognized in northeast Brazil, where concerns over its possible links with infant microcephaly have been discussed. Providing a causal link between ZIKV infection and birth defects is still a challenge. MicroRNAs (miRNAs) are small noncoding RNAs (sncRNAs) that regulate post-transcriptional gene expression by translational repression, and play important roles in viral pathogenesis and brain development. The potential for flavivirus-mediated miRNA signalling dysfunction in brain-tissue development provides a compelling hypothesis to test the perceived link between ZIKV and microcephaly. METHODOLOGY/PRINCIPAL FINDINGS: Here, we applied in silico analyses to provide novel insights to understand how Congenital ZIKA Syndrome symptoms may be related to an imbalance in miRNAs function. Moreover, following World Health Organization (WHO) recommendations, we have assembled a database to help target investigations of the possible relationship between ZIKV symptoms and miRNA-mediated human gene expression. CONCLUSIONS/SIGNIFICANCE: We have computationally predicted both miRNAs encoded by ZIKV able to target genes in the human genome and cellular (human) miRNAs capable of interacting with ZIKV genomes. Our results represent a step forward in the ZIKV studies, providing new insights to support research in this field and identify potential targets for therapy.

Draft Genome Sequence of Hydrotalea flava Strain CCUG 51397T.

We report the draft genome sequence of Hydrotalea flava CCUG 51397(T), the type strain of the genus Hydrotalea (family Chitinophagaceae), isolated from water samples in southern Sweden.