Microorganisms最新文献

Slow decomposition rates of cereal crop residues can lead to agronomic challenges, such as nutrient immobilization, delayed soil warming, and increased pest pressures. In this regard, microbial inoculation with efficient strains offers a viable and eco-friendly solution to accelerating the decomposition process of crop residues. However, this solution often focuses mostly on selecting microorganisms based on the appropriate enzymic capabilities and neglects the metabolic versatility required to utilize both structural and non-structural components of residues. Therefore, this study aimed to address these limitations by assessing the metabolic profiles of five previously identified cellulolytic bacterial strains, including Bacillus pumilus 1G17, Micromonospora chalcea 1G49, Bacillus mobilis 5G17, Streptomyces canus 1TG5, and Streptomyces achromogenes 3TG21 using Biolog Phenotype Microarray analysis. Moreover, this study evaluated the impact of wheat straw inoculation with single strains and a bacterial consortium on soil organic carbon and nitrogen content in a pot experiment. Results revealed that, beyond the core subset of 12 carbon sources, the strains exhibited diverse metabolic capacities in utilizing 106 carbon sources. All strains demonstrated effective straw biomass degradation compared to the negative control, with significant differences detected only in oil seed rape straw biodegradation estimations. Furthermore, wheat straw inoculated with a bacterial consortium showed a significant increase in soil organic carbon content after 180 days in the pot experiment. Overall, these findings underscore the critical role of metabolic profiling in gaining a deeper understanding of microbial capabilities and addressing the complexities of residue composition and environmental variability.

Chronic endometritis (CE) is a persistent inflammatory condition of the endometrium characterized by abnormal infiltration of plasma cells into the endometrial stroma. Frequently associated with repeated implantation failure, recurrent pregnancy loss, and infertility, CE significantly impacts women's health, contributing to conditions such as abnormal uterine bleeding and endometriosis. Treatment typically involves antibiotic therapy; however, the efficacy of these treatments is increasingly compromised by the rise of antimicrobial resistance (AMR). This paper examines the critical links between AMR and CE, proposing strategies to enhance clinical management and optimize treatment outcomes.

Linezolid is an oxazolidinone antibiotic and is considered a last-resort treatment option for serious infections caused by problematic Gram-positive pathogens, including vancomycin-resistant enterococci. The present study aimed to explore the linezolid resistance mechanisms and genomic characteristics of two vancomycin-susceptible Enterococcus faecalis isolates from Bulgaria. The strains designated Efs2503-bg (inpatient from Pleven) and Efs966-bg (outpatient from Varna) were recovered from wounds in 2018 and 2023, respectively. Antimicrobial susceptibility testing, whole-genome sequencing, multilocus sequence typing, and phylogenomic analysis based on 332 linezolid-resistant E. faecalis genomes were performed. Efs2503-bg was high-level resistant to linezolid (MIC > 256 mg/L) and displayed the G2576T mutation affecting three of the four 23S rDNA loci. Efs966-bg (MIC = 8 mg/L) carried a plasmid-located optrA determinant surrounded by fexA and ermA. No mutations in the genes encoding for ribosomal proteins L3, L4, and L22 were detected. The isolates belonged to the sequence types ST6 (Efs2503-bg) and ST1102 (Efs966-bg). Phylogenomic analysis revealed that Efs2503-bg and Efs966-bg are genetically distinct, with a difference of 12,051 single-nucleotide polymorphisms. To our knowledge, this is the first report of linezolid-resistant enterococci in Bulgaria. Although the global incidence of linezolid-resistant enterococci is still low, their emergence is alarming and poses a growing clinical threat to public health.

Infertility, both primary and secondary, is strongly influenced by microbiological factors, with the vaginal microbiota playing a key role in reproductive health.

Objective: The aim of this study was to characterize the vaginal microbiota of 136 Mexican women diagnosed with infertility-primary (n = 58) and secondary (n = 78)-by evaluating the presence of pathogenic bacterial species and their associations with infertility conditions.

Methods: Samples were obtained through cervical swabs, and microorganism identification was performed using qPCR techniques.

Results: Analysis revealed a positive correlation between increased age and the likelihood of primary infertility, as well as a negative correlation with secondary infertility. Significant differences in microbial composition were also observed between the two infertility groups. Lactobacillus crispatus and Lactobacillus gasseri were dominant in women with primary infertility, in addition to a high prevalence of Gardnerella vaginalis and Fannyhessea vaginae. Additionally, correlations were found between the presence of human papillomavirus (HPV) and sexually transmitted bacteria, as well as Gardnerella vaginalis.

Conclusion: Our findings suggest that the composition of the vaginal microbiota may play a decisive role in infertility, highlighting the need for personalized therapeutic strategies based on microbial profiles.

The significant microbiota variability represents a key feature that makes the full comprehension of the functional interaction between microbiota and the host an ongoing challenge. To overcome this limitation, in this study, fish intestinal microbiota was analyzed through a meta-analysis, identifying the core microbiota and constructing stochastic Bayesian network (BN) models with SAMBA. We combined three experiments performed with gilthead sea bream juveniles of the same hatchery batch, reared at the same season/location, and fed with diets enriched on processed animal proteins (PAP) and other alternative ingredients (NOPAP-PP, NOPAP-SCP). Microbiota data analysis disclosed a high individual taxonomic variability, a high functional homogeneity within trials and highlighted the importance of the core microbiota, clustering PAP and NOPAP fish microbiota composition. For both NOPAP and PAP BNs, >99% of the microbiota population were modelled, with a significant proportion of bacteria (55-69%) directly connected with the diet variable. Functional enrichment identified 11 relevant pathways expressed by different taxa across the different BNs, confirming the high metabolic plasticity and taxonomic heterogeneity. Altogether, these results reinforce the comprehension of the functional bacteria-host interactions and in the near future, allow the use of microbiota as a species-specific growth and welfare benchmark of livestock animals, and farmed fish in particular.

This study investigated the diagnostic efficiencies of two assays for the detection of Mycobacterium tuberculosis complex: (1) the reciprocal-flow real-time polymerase chain reaction (PCR)-based GeneSoC assay and (2) the real-time PCR based GENECUBE MTB assay with quenching probe. These assays were performed for stored clinical samples and results were compared with the confirmed results based on culture and COBAS TaqMan MTB assay. A total of 53 samples (20 confirmed positives and 33 confirmed negatives) were included in the performance analysis. The GeneSoC assay showed concordance in all 53 samples, regardless of specimen type, while the GENECUBE MTB assay showed concordance in 19 of the 20 confirmed positive samples and all 33 confirmed negative samples. The overall agreement was 100.0% for the GeneSoC assay and 98.1% for the GENECUBE MTB assay. Positive and negative percent agreements were 100.0% each for the GeneSoC assay and 95.0% and 100.0%, respectively, for the GENECUBE MTB assay. Both the GeneSoC and GENECUBE MTB assays exhibited excellent performance in detecting M. tuberculosis complex. The GeneSoC assay is useful for independent assays of individual samples, whereas the GENECUBE MTB assay is suitable for batch assays of multiple samples.

Abscess-forming cervical bacterial infections are rare and serious infections. Methods: We retrospectively examined the trends in abscess-forming cervical bacterial infections in children who required inpatient treatment in three periods before (January 2016 to June 2020), during (July 2020 to December 2022) and after the COVID-19 pandemic (January 2023 to June 2024). Results: The study included 96 patients with superficial cervical abscesses and 111 patients with deep cervical abscesses (34 with retropharyngeal abscesses, 51 with peritonsillar abscesses, and 26 with deep neck abscesses). Both decreased during the COVID-19 pandemic and increased significantly after the COVID-19 pandemic compared to before the COVID-19 pandemic (0.94 ± 0.92 vs. 0.50 ± 0.72 vs. 1.67 ± 1.11/month, 0.93 ± 0.96 vs. 0.60 ± 0.84 vs. 2.39 ± 1.70/month), which was related with the trends of respiratory viral infections. Bacteria were identified in 79 of the 97 cases in which punctures were performed; however, there were no significant differences between the three periods. No significant changes were found in the pharyngeal streptococcal antigen positivity rate, rate of oral antibiotic use before hospitalization, length of hospital stay, or duration of antibiotic administration before and after the COVID-19 pandemic. Conclusions: The COVID-19 pandemic has affected the epidemiology of cervical abscess-forming bacterial infections in children. Although the reemergence of respiratory viral infections after the COVID-19 pandemic may be a factor, the cause of the doubling in the number of neck abscesses after the COVID-19 pandemic remains unclear and requires further investigation.

Radiation-induced skin toxicity, resulting from ionizing or nonionizing radiation, is a common skin disorder. However, the underlying relationship between skin microbiota and radiation-induced skin toxicity remains largely unexplored. Herein, we uncover the microbiota-skin interaction based on a genome-wide association study (GWAS) featuring 150 skin microbiota and three types of skin microenvironment. Summary datasets of human skin microbiota were extracted from the GWAS catalog database, and summary datasets of radiation-induced skin toxicity from the FinnGen biobank. Mendelian Randomization (MR) analysis was leveraged to sort out the causal link between skin microbiota and radiation-induced skin toxicity. We identified 33 causal connections between human skin microbiota and radiation-induced skin toxicity, including 19 positive and 14 negative causative directions. Among these potential associations, the genus Staphylococcus could serve as a common risk factor for radiation-induced skin toxicity, especially for radiodermatitis. And Streptococcus salivarius was identified as a potential protective factor against radiation-induced skin toxicity. Additional analysis indicated no pleiotropy, heterogeneity, or reverse causal relationship in the results. We comprehensively assessed potential associations of skin microbiota with radiation-induced skin toxicity and identified several suggestive links. Our results provide promising targets for the prevention and treatment of radiation-induced skin toxicity.

Up to one-quarter of the United States population is affected by tinea pedis (athlete's foot). Tinea pedis of the web space (interdigital tinea pedis) is a common clinical presentation causing skin macerations and fissures. A "dermatophytosis complex" (i.e., concomitant bacterial colonization) further complicates treatment. Here, we examined records of 14,429 skin specimens taken from the feet of dermatology and podiatry outpatients over a 4.6-year period; all specimens were subjected to multiplex qPCR diagnosis for the detection of dermatophytes, Candida, Corynebacterium minutissimum, Pseudomonas and Staphylococcus aureus. A literature search was conducted to review the reported prevalence of fungal and bacterial agents. In both interdigital and plantar foot specimens, dermatophytes (33.3-33.8%) and S. aureus (24.3-25%) were found to be the predominate pathogens. In the interdigital space, a higher prevalence of C. minutissimum (15.7% vs. 7.9%) and Pseudomonas (23.5% vs. 9.6%) was found. The detection of Pseudomonas was more likely to be observed in the presence of Candida, reflecting a higher risk of mixed infection. In dermatophyte-positive specimens, the "dermatophytosis complex" variant was observed at 45.5% (SD: 2.3). An analysis of patient characteristics showed male patients exhibiting higher likelihoods for dermatophyte, C. minutissimum, Pseudomonas and S. aureus detections. The elderly were disproportionately infected with Candida. In children, an S. aureus detection was more common, which could be attributed to impetigo. The recent literature lacks reporting on concomitant bacterial colonization in tinea pedis patients, likely due to the reliance on fungal culture supplemented with antibiotics. Geographical variation has been identified in the detection of the Trichophyton mentagrophytes complex. In conclusion, PCR diagnosis serves as a valuable tool for the management of tinea pedis. An accurate and timely detection of fungal pathogens and concomitant bacterial colonization can better inform healthcare providers of appropriate treatment selection.