Taken together, we propose that OsNRAMP2 transports Fe from the vacuole to the cytosol and plays a pivotal role in seed germination.Glycerol (Gly) can be dissimilated by two pathways in bacteria. Either this sugar alcohol is first oxidized to dihydroxyacetone (DHA) and then phosphorylated or it is first phosphorylated to glycerol-3-phosphate (GlyP) followed by oxidation. Oxidation of GlyP can be achieved by NAD-dependent dehydrogenases or by a GlyP oxidase. In both cases, dihydroxyacetone phosphate is the product. Genomic analysis showed that Enterococcus faecium harbors numerous genes annotated to encode activities for the two pathways. Selleckchem Thiazovivin However, our physiological analyses of growth on glycerol showed that dissimilation is limited to aerobic conditions and that despite the presence of genes encoding presumed GlyP dehydrogenases, the GlyP oxidase is essential in this process. Although E. faecium contains an operon encoding the phosphotransfer protein DhaM and DHA kinase, which are required for DHA phosphorylation, it is unable to grow on DHA. This operon is highly expressed in stationary phase but its physiological role remains unknown. Finally, data obtained from sequencing of a transposon mutant bank of E. faecium grown on BHI revealed that the GlyP dehydrogenases and a major intrinsic family protein have important but hitherto unknown physiological functions.Antimicrobial materials are tools used to reduce the transmission of infectious microorganisms. Photo-illuminated titania (TiO2) is a known antimicrobial material. Used as a coating on door handles and similar surfaces, it may reduce viability and colonization by pathogens and limit their spread. We tested the survival of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Saccharomyces cerevisiae on a nano-structured TiO2-based thin film, called 'NsARC', and on stainless steel under a variety of light wavelengths and intensities. There was significantly less survival (P less then 0.001) of all the organisms tested on NsARC compared to inert uncoated stainless steel under all conditions. NsARC was active in the dark and possible mechanisms for this are suggested. NsARC inhibited biofilm formation as confirmed by scanning electron microscopy. These results suggest that NsARC can be used as a self-cleaning and self-sterilizing antimicrobial surface coating for the prevention and reduction in the spread of potentially infectious microbes.
Tumor-induced osteomalacia (TIO) is a paraneoplastic disorder, usually caused by benign mesenchymal tumors that produce high levels of the hormone fibroblast-growth-factor 23 (FGF23). The only curative therapy of the disease is resection of the causative tumors. This research was conducted to evaluate the efficacy of 18F-AlF-NOTA-octreotide ( 18F-OC) PET/CT in detecting TIO and its impact on patient management.
Retrospective analysis of 17 patients with hypophosphatemic osteomalacia suspected of TIO was performed. 18F-OC PET/CT study was performed in all 17 patients to localize the tumor. 68Ga-DOTATATE PET/CT was performed in 4 out of 17 patients. 18F-OC and 68Ga-DOTATATE PET/CT studies were performed within 1 week of each other. Both studies were interpreted blindly without the knowledge of other imaging findings. The image findings were compared with the results of histopathological examinations and clinical follow-ups.
18F-OC PET/CT scans were positive in 14 patients. Moreover, 4 out of 14 patients were performed with both 18F-OC and 68Ga-DOTATATE PET/CT. Both studies were able to localize the tumor in all the 4 patients. In total, 14 patients had surgery to remove the lesions. Postsurgical pathological examination confirmed causative tumors in these patients whose symptoms diminished promptly. The serum phosphate levels became normal confirming the diagnosis of TIO. 18F-OC PET/CT sensitivity, specificity and accuracy were 87.5%, 100% and 88.2% respectively. 18F-OC PET/CT findings affected patient management in 88.2% of cases.
18F-OC PET/CT scan is useful in the detection of tumors causing TIO. Further studies with larger patient population are needed to validate the result.
18F-OC PET/CT scan is useful in the detection of tumors causing TIO. Further studies with larger patient population are needed to validate the result.Transcription factor (TF)-based biosensors have proven useful for increasing biomanufacturing yields, large-scale functional screening, and in environmental monitoring. Most yeast TF-based biosensors are built from natural promoters, resulting in large DNA parts retaining considerable homology to the host genome, which can complicate biological engineering efforts. There is a need to explore smaller, synthetic biosensors to expand the options for regulating gene expression in yeast. Here, we present a systematic approach to improving the design of an existing oxidative stress sensing biosensor in Saccharomyces cerevisiae based on the Yap1 transcription factor. Starting from a synthetic core promoter, we optimized the activity of a Yap1-dependent promoter through rational modification of a minimalist Yap1 upstream activating sequence. Our novel promoter achieves dynamic ranges of activation surpassing those of the previously engineered Yap1-dependent promoter, while reducing it to only 171 base pairs. We demonstrate that coupling the promoter to a positive-feedback-regulated TF further improves the biosensor by increasing its dynamic range of activation and reducing its limit of detection. We have illustrated the robustness and transferability of the biosensor by reproducing its activity in an unconventional probiotic yeast strain, Saccharomyces boulardii. Our findings can provide guidance in the general process of TF-based biosensor design.Environmental pH and gut transit rate are the key factors determining the dynamics of colonic microbiota. In this study, the effect of changing pH on the composition and metabolism of pooled faecal microbiota was elucidated at physiologically relevant dilution rates Dhigh = 0.2 and Dlow = 0.05 1/h. The results showed the best adaptability of Bacteroides ovatus within the pH range 6.0-8.0 at both dilution rates. The butyrate producing Faecalibacterium and Coprococcus comes were extremely sensitive to pH > 7.5, while the abundance of Akkermansia muciniphila increased significantly at pH >7 at Dhigh, causing a pH-dependant shift in the dynamics of mucin degrading species. Increased gas formation was observed at pH 7, consistent with the simultaneous increased abundance of Methanobrevibacter smithii. Our study confirmed the importance of pH in the development of faecal microbiota in pectin-supplemented medium. Fermentation of other dietary fibres can be studied using the same approach. The significance of pH should be more emphasized in gut research and diagnostics.Selleckchem Thiazovivin
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