Frontiers in Microbiology最新文献

Introduction: Bovine torovirus (BToV), Bovine enterovirus (BEV), Bovine norovirus (BNoV), Bovine coronavirus (BCoV), Bovine rotavirus (BRV), and Bovine viral diarrhea virus (BVDV) are significant pathogens causing diarrhea in calves, characterized by their high prevalence and challenging prevention and control measures.

Methods: We analyzed 295 calf diarrhea samples, amplifying the M gene from BToV-positive samples, the 5'UTR gene from BEV-positive samples, the RdRp gene from BNoV-positive samples, the VP7 gene from BRV-positive samples, the S gene from BCoV-positive samples, and the 5'UTR gene from BVDV-positive samples. Subsequent homology analysis and phylogenetic tree construction were performed.

Results: The overall viral positive rate in Guangdong Province was 21.36%. Specific detection rates were as follows: Foshan City at 50.00% (18/36), Guangzhou City at 43.90% (36/82), Huizhou City at 21.21% (7/33), Yangjiang City at 2.08% (1/48), Meizhou City at 1.39% (1/72), and Heyuan City at 0.00% (0/24). The detection rates for BToV, BEV, BNoV, BCoV, BRV, and BVDV were 0.34% (1/295), 6.10% (18/295), 0.68% (2/295), 1.36% (4/295), 10.85% (32/295), and 2.03% (6/295), respectively. Notably, the highest overall virus detection rate was observed in the Guangzhou-Foshan region, with BRV and BEV showing the highest detection rates among the six viruses. This study marks the first report of BToV and BNoV in Guangdong Province. Phylogenetic analysis revealed that the BToV strain belonged to type II, sharing genetic similarities with epidemic strains from various provinces in China. The BEV strains were categorized into E and F types, with the F type being the predominant strain in Guangdong Province and exhibiting the closest genetic relationship to strains from Heilongjiang and Guangxi. The BNoV strains, along with Hebei strains, were identified as GIII.2 subgenotype. BCoV strains showed the highest genetic similarity to strains from Sichuan. All BRV strains were classified under the G6 subtype and had the closest genetic relationship with human rotavirus strains. BVDV strains were identified as subtype 1b, closely related to the Beijing strain. In conclusion, this study investigated the prevalence and evolutionary characteristics of diarrhea-associated viruses in calves in specific areas of Guangdong Province, providing a valuable reference for establishing effective prevention and control measures in cattle farms.

The emergence of porcine deltacoronavirus (PDCoV) presents a significant threat to both human and animal health due to its ability to cause highly contagious enteric diseases. This underscores the crucial need for timely and accurate diagnosis to facilitate effective epidemiological investigation and clinical management. This research aimed to establish a visual detection method based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) for PDCoV testing. In this study, six pairs of primers were designed according to the conserved sequences of PDCoV ORF1a/b genes. The primer sets and parameters that affect LAMP reaction were optimized. The visual RT-LAMP method was developed by incorporating methyl red into the optimized reaction system, it exclusively detected PDCoV without cross-reactivity with other viruses and the detection limits for PDCoV could reach 10 copies/μL. In comparison with RT-PCR for testing 132 clinical samples, the relative specificity and sensitivity of the visual RT-LAMP were found to be 99.2 and 100%, respectively, with a concordance rate of 99.2% and a kappa value of 0.959, indicating that the visual RT-LAMP is a reliable method for the application of PDCoV detection in clinical samples.

The bottled drinking water market has seen significant growth and diversification, yet the selection criteria lack scientific basis, as all must adhere to stringent health standards. Prior studies predominantly focused on chemical quality, with limited assessments of microbial quality using methods prone to underestimation. Moreover, insufficient research explores the impact of packaging materials and temperatures optimal for mesophilic growth on microbial quality. To understand the unique characteristics and justify the distinction among different types of bottled waters, a comprehensive analysis encompassing both chemical and microbiological aspects is imperative. Addressing these gaps, our study examines 19 diverse bottled water brands comprising purified, mineral, artesian, and sparkling water types from Saudi Arabia and abroad. Our findings reveal distinct chemical compositions among bottled waters, with notable variations across types. Flow cytometry analysis reveals significant differences in bacterial content among water types, with natural mineral waters having the highest concentrations and treated purified waters the lowest. Bacterial content in plastic-bottled mineral water suggests it may be higher than in glass-bottled water. Flow cytometry fingerprints highlight separate microbial communities for purified and mineral waters. Additionally, temperatures favorable for mesophilic growth reveal varying microbial responses among different types of bottled waters. Some variation is also observed in mineral water bottled in plastic versus glass, suggesting potential differences that warrant further investigation. 16S rRNA gene sequencing identifies unique microbial taxa among different mineral waters. Overall, our study underscores that all bottled waters meet health regulations. Furthermore, the combined chemical and microbial profiles may serve as authenticity indicators for distinct bottled water types. This study can serve as a basis for future research on the environmental impact of bottled water transportation, suggesting that locally produced water may offer a more sustainable option.

Background: The gut microbiota (GM) plays a pivotal role in influencing various health outcomes, including immune-mediated conditions, but its potential association with autoimmune thyroid disease (AITD) remains underexplored. We aimed to investigate the potentially pathogenic or protective causal impacts of specific GM on two types of AITD, namely Graves' disease and Hashimoto's thyroiditis, and analyzed the mediating effect of 731 immune cell phenotypes.

Methods: Leveraging pooled genome-wide association study (GWAS) data of 211 gut microbiota traits, 731 immune cell phenotypes, and two types of AITD (Hashimoto's thyroiditis and Graves' disease), we performed bidirectional Mendelian randomization (MR) analyses to explore the causal relationships between the GM and AITD. Subsequently, we employed a multivariable MR analysis to discover potential mediating immune cell traits. Additionally, sensitivity analyses were utilized to ensure the reliability of the outcomes.

Results: Our analysis revealed that a total of 7 GM taxa were positively associated with AITD, and other 14 taxa showed a negative correlation with AITD. Furthermore, we identified several immune cell traits that mediated the effects of GM on AITD. Most notably, Actinobacteria (p) presented protective effects on Hashimoto's thyroiditis via CCR2 on myeloid Dendritic Cell (5.0%), and Bifidobacterium (g) showed facilitating effects on Graves' disease through CD39+ CD4+ T cell %CD4+ T cell (5.0%) and CD14 on CD33+ HLA DR+ CD14dim (12.2%).

Conclusion: The current MR study provides evidence supporting the causal relationships between several specific GM taxa and AITD, and further identified potential mediating immunophenotypes.

This study aimed to investigate the effects of the cell-free supernatant of Lactiplantibacillus plantarum ATCC^® 10241^TM on the biofilm-forming capacity of Pseudomonas aeruginosa strains isolated from cystic fibrosis (CF) patients. In addition, the study evaluated the in vivo potential of the cell-free supernatant to modulate inflammation and reduce lung damage in mice infected with P. aeruginosa strains or co-challenged with P. aeruginosa and the Streptococcus milleri group (SMG). The results showed that CF-derived P. aeruginosa strains can infect the respiratory tract of adult mice, inducing local inflammation and lung damage. The severity of these infections was exacerbated when P. aeruginosa was co-administered with SMG. Notably, nebulization with the cell-free supernatant of L. plantarum produced beneficial effects, reducing respiratory infection severity and inflammatory responses induced by P. aeruginosa, both alone or in combination with SMG. Reduced bacterial loads and lung damage were observed in supernatant-treated mice compared to controls. Although further mechanistic studies are necessary, the results show that the cell-free supernatant of L. plantarum ATCC^® 10241^TM is an interesting adjuvant alternative to treat P. aeruginosa respiratory infections and superinfections in CF patients.

The purpose of this study was to investigate the effects of intestinal microbiota on the growth and production performance of different groups of sheep, focusing on the role of cecal microbiota in regulating intestinal function, enhancing digestion and absorption, and improving feed utilization. The production performance of MG × STH (Mongolia × Small Tailed Han) F1 hybrids and purebred STH (Small Tailed Han) sheep by measuring various factors, including enzyme activities and VFAs (volatile fatty acids), to analyze changes in cecal fermentation parameters across different sheep groups. Metagenomic and metabolomic sequencing combined with bioinformatics to analyze the cecal contents of the two sheep populations. The study findings indicated that the MG × STH F1 hybrids outperformed the purebred STH in terms of body weight, height, oblique body length, and VFAs (p < 0.05). Additionally, the MG × STH F1 higher levels of protease and cellulase in the cecum compared to the purebred sheep (p < 0.05). Metagenomic analysis identified 4,034 different microorganisms at the species level. Five differential organisms (Akkermansiaceae bacterium, Escherichia coli, unclassified p Firmicutes, Streptococcus equinus, Methanobrevibacter millerae) positively regulated sheep performance. Metabolomics identified 822 differential metabolites indoleacetaldehyde, 2-aminobenzoic acid, phenyl-Alanine, enol-phenylpyruvate and n-acetylserotonin were associated with improved performance of sheep. The combined results from the metagenomic and metabolomic studies suggest a positive correlation between specific microbes and metabolites and the performance of the sheep. In conclusion, the MG × STH F1 hybrids demonstrated superior growth performance compared to the purebred STH sheep. The identified microorganisms and metabolites have promising roles in positively regulating sheep growth and can be considered key targets for enhancing sheep performance.