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Dental caries is a biofilm-mediated disease with Streptococcus mutans as the main pathogenic microorganism, and its incidence is closely related to sucrose. Rubusoside is a natural non-nutritive sweetener isolated from Rubus suavissimu S.Lee. This study was designed to determine the effect of the sucrose substitute on cariogenic properties and virulence gene expression of S. mutans biofilms. S. mutans was exposed to BHI medium (as a control), BHI+1% sucrose, BHI+1% rubusoside, and BHI +1% xylitol. The growth curve of biofilm was monitored with crystal violet staining and pH was measured every 24 h. After 5 days, the biofilms formed on the glass coverslips were recovered to determine the biomass (dry weight and total soluble proteins), colony-forming units, and intra- and extracellular polysaccharides. Biofilm structural imaging was observed using a scanning electron microscope (SEM). The virulence gene expression (gtfB, gtfC, gtfD, ftf, spaP, gbpB, ldh, atpF, vicR, and comD) was determined by rt-qPCR. Comparence factors of S. mutans, massive commercial products have oriented towards developing sucrose substitutes. Rubusoside, a natural sucrose substitute, is a plant extract with high sweetness. Although some studies have shown that rubusoside do not produce acids and inhibit the growth of S. mutans, little attention has been paid to dental biofilm and underlying mechanisms. Our study focuses on the effect of rubusoside on formation and structure of biofilm, and expression of virulence genes. Results confirms that rubusoside can inhibit accumulation, bacterial viability, polysaccharide production of biofilm, and inhibit related gene expression. These results provide further insight into the cariogenicity of S. mutans biofilm, and demonstrate a new perspective for studying the impact of sucrose substitutes on caries.Many biological contaminants are disseminated through water, and their occurrence has potential detrimental impacts on public and environmental health. Conventional monitoring tools rely on cultivation and are not robust in addressing modern water quality concerns. This review proposes metagenomics as a means to provide a rapid, nontargeted assessment of biological contaminants in water. When further coupled with the appropriate methods (e.g., quantitative PCR and flow cytometry) and bioinformatic tools, metagenomics can provide information concerning both the abundance and diversity of biological contaminants in reclaimed waters. Further correlation between the metagenomic-derived data of selected contaminants and the measurable parameters of water quality can also aid in devising strategies to alleviate undesirable water quality. Here, we reviewed metagenomic approaches (i.e., both sequencing platforms and bioinformatic tools) and studies that demonstrated their use for reclaimed water quality monitoring. We also provide recommendations on areas of improvement that will allow metagenomics to significantly impact how the water industry performs reclaimed water quality monitoring in the future.The purple non-sulfur bacterium Rhodopseudomonas palustris TIE-1 can produce useful biochemicals such as bioplastics and biobutanol. Production of such biochemicals requires intracellular electron availability, which is governed by the availability and the transport of essential metals such as iron (Fe). Because of the distinct chemical properties of ferrous [Fe(II)] and ferric iron [Fe(III)], different transport systems are required for their transport and storage in bacteria. Although Fe(III) transport systems are well characterized, we know much less about Fe(II) transport systems except for the FeoAB system. Iron transporters can also import manganese (Mn). Here, we study Fe and Mn transport by five putative Fe transporters in TIE-1 under metal-replete, -deplete, oxic and anoxic conditions. We observe that by overexpressing feoAB, efeU, and nramp1AB, the intracellular concentration of Fe and Mn can be enhanced in TIE-1, under oxic and anoxic conditions, respectively. The deletion of a single gene/operon dintracellular electron availability, which in turn is mediated by various iron-containing proteins in the cell. Several putative Fe transporters exist in TIE-1's genome. Some of these transporters can also transport Mn, part of several important cellular enzymes. Therefore, understanding the ability to transport and respond to varying levels of Fe and Mn under different conditions is important to improve TIE-1's ability to produce useful biomolecules. Our data suggest that by overexpressing Fe transporter genes via plasmid-based expression, we can increase the import of Fe and Mn in TIE-1. Future work will leverage these data to improve TIE-1 as an attractive microbial chassis and future biotechnological workhorse.Bacterial alkane metabolism is associated with a number of cellular stresses, including membrane stress, oxidative stress, and the limited uptake of charged ions such as sulfate. In the present study, the genes ssuD and tauD in Acinetobacter oleivorans DR1 cells, which encode an alkanesulfonate monooxygenase and a taurine dioxygenase, respectively, were found to be responsible for hexadecanesulfonate (C16SO3H) and taurine metabolism, and Cbl was experimentally identified as a potential regulator of ssuD and tauD expression. The expression of ssuD and tauD occurred under sulfate-limited conditions generated during n-hexadecane degradation. Interestingly, expression analysis and knockout experiments suggested that both genes are required to protect cells against oxidative stress, including that generated by n-hexadecane degradation and H2O2 exposure. Measurable levels of intracellular hexadecanesulfonate were also produced during n- hexadecane degradation. Phylogenetic analysis suggested that ssuD and tauD are mainly present in soil-dwelling aerobes within the β- and γ- proteobacteria classes, which suggests that they function as controllers of the sulfur cycle and play a protective role against oxidative stress in sulfur-limited conditionsIMPORTANCE Alkanesulfonate monooxygenase (ssuD) and taurine dioxygenase (tauD), which play a role in the degradation of organosulfonate, were expressed during n-hexadecane metabolism and oxidative stress conditions in Acinetobacter oleivorans DR1. Our study confirmed that hexadecanesulfonate was accidentally generated during bacterial n-hexadecane degradation in sulfate-limited conditions. Removal of this byproduct by SsuD and TauD must be necessary for bacterial survival under oxidative stress generated during n-hexadecane degradation.Plants mount defense responses by recognizing indicators of pathogen invasion, including microbe-associated molecular patterns (MAMPs). read more Flagellin, from the bacterial pathogen Pseudomonas syringae pv. tomato (Pst), contains two MAMPs, flg22 and flgII-28, that are recognized by tomato (Solanum lycopersicum) receptors Flagellin sensing 2 (Fls2) and Flagellin sensing 3 (Fls3, respectively, but to what degree each receptor contributes to immunity and if they promote immune responses using the same molecular mechanisms are unknown. Here, we characterized CRISPR/Cas9-generated Fls2 and Fls3 tomato mutants and found the two receptors contribute equally to disease resistance both on the leaf surface and in the apoplast. However, we observed striking differences in certain host responses mediated by the two receptors. Compared to Fls2, Fls3 mediated a more sustained production of reactive oxygen species (ROS) and an increase in transcript abundance of 44 tomato genes, with two genes serving as specific reporters for the Fls3 pathway. Fls3 had greater in vitro kinase activity than Fls2 and could transphosphorylate a substrate. Using chimeric Fls2/Fls3 proteins, we found no evidence that a single receptor domain is responsible for the Fls3 sustained ROS, suggesting involvement of multiple structural features or a nullified function of the chimeric construct. link2 This work reveals differences in certain immunity outputs between Fls2 and Fls3, suggesting they might use distinct molecular mechanisms to activate pattern-triggered immunity in response to flagellin-derived MAMPs.Vivipary, wherein seeds germinate prior to dispersal while still associated with the maternal plant, is an adaptation to extreme environments. It is normally inhibited by the establishment of dormancy. The genetic framework of vivipary has been well studied; however, the role of epigenetics in vivipary remains unknown. Here, we report that silencing of METHYLTRANSFERASE1 (SlMET1) promoted precocious seed germination and seedling growth within the tomato (Solanum lycopersicum) epimutant Colourless non-ripening (Cnr) fruits. This was associated with decreases in abscisic acid (ABA) concentration and levels of mRNA encoding 9-cis-epoxycarotenoid-dioxygenase (SlNCED), which is involved in ABA biosynthesis. Differentially methylated regions were identified in promoters of differentially expressed genes, including SlNCED. SlNCED knockdown also induced viviparous seedling growth in Cnr fruits. link3 Strikingly, Cnr ripening reversion suppressed vivipary. Moreover, neither SlMET1/SlNCED-VIGS nor transgenic SlMET1-RNAi produced vivipary in wild-type tomatoes; the latter affected leaf architecture, arrested flowering and repressed seed development. Thus, a dual pathway in ripening and SlMET1-mediated epigenetics coordinates the blockage of seed vivipary.Skeletal muscle biopsy remains an important investigative tool in the diagnosis of a variety of muscle disorders. Traditionally, someone with a limb-girdle muscle weakness, myopathic changes on electrophysiology and raised serum creatine kinase (CK) would have a muscle biopsy. However, we are living through a genetics revolution, and so do all such patients still need a biopsy? When should we undertake a muscle biopsy in patients with a distal, scapuloperoneal or other patterns of muscle weakness? When should patients with myositis, rhabdomyolysis, myalgia, hyperCKaemia or a drug-related myopathy have a muscle biopsy? What does normal muscle histology look like and what changes occur in neurogenic and myopathic disorders? As with Kipling's six honest serving men, we hope that by addressing these issues we can all become more confident about when to request a muscle biopsy and develop clearer insights into muscle pathology.Chimeric antigen receptor (CAR) T-cell therapy is one of the most innovative therapies for haematological malignancies to emerge in a generation. Clinical studies have shown that a single dose of CAR T-cells can deliver durable clinical remissions for some patients with B-cell cancers where conventional therapies have failed.A significant complication of CAR therapy is the immune effector cell-associated neurotoxicity syndrome (ICANS). This syndrome presents a continuum from mild tremor to cerebral oedema and in a minority of cases, death. Management of ICANS is mainly supportive, with a focus on seizure prevention and attenuation of the immune system, often using corticosteroids. Parallel investigation to exclude other central nervous system pathologies (infection, disease progression) is critical. In this review, we discuss current paradigms around CAR T-cell therapy, with a focus on appropriate investigation and management of ICANS.