To accelerate differentiation between Staphylococcus aureus and Coagulase Negative Staphylococci (CNS), this study aimed to compare six different DNA extraction methods from 2 commonly used blood culture materials, i.e. BACTEC and Bact/ALERT. Furthermore, we analyzed the effect of reduced blood culture times for detection of Staphylococci directly from blood culture material. A real-time PCR duplex assay was used to compare 6 different DNA isolation protocols on two different blood culture systems. Negative blood culture material was spiked with MRSA. Bacterial DNA was isolated with: automated extractor EasyMAG (3 protocols), automated extractor MagNA Pure LC (LC Microbiology Kit MGrade), a manual kit MolYsis Plus, and a combination between MolYsis Plus and the EasyMAG. The most optimal isolation method was used to evaluate reduced bacterial culture times. Bacterial DNA isolation with the MolYsis Plus kit in combination with the specific B protocol on the EasyMAG resulted in the most sensitive detection of S.aureus, with a detection limit of 10 CFU/ml, in Bact/ALERT material, whereas using BACTEC resulted in a detection limit of 100 CFU/ml. An initial S.aureus load of 1 CFU/ml blood can be detected after 5 hours of culture in Bact/ALERT3D by combining the sensitive isolation method and the tuf LightCycler assay.
From the article: "Scope: During food processing, the Maillard reaction ( М R) may occur, resulting in the formation of glycated proteins. Glycated proteins are of particular importance in food allergies because glycation may influence interactions with the immune system. This study compared native and extensively glycated milk allergen β -lactoglobulin (BLG), in their interactions with cells crucially involved in allergy. Methods and results: BLG was glycated in MR and characterized. Native and glycated BLG were tested in experiments of epithelial transport, uptake and degradation by DCs, T-cell cytokine responses, and basophil cell degranulation using ELISA and flow cytometry. Glycation of BLG induced partial unfolding and reduced its intestinal epithelial transfer over a Caco-2 monolayer. Uptake of glycated BLG by bone marrow–derived dendritic cells (BMDC) was increased, although both BLG forms entered BMDC via the same mechanism, receptor-mediated endocytosis. Once inside the BMDC, glycated BLG was degraded faster, which might have led to observed lower cytokine production in BMDC/CD4 + T-cells coculture. Finally, glycated BLG was less efficient in induction of degranulation of BLG-specific IgE sensitized basophil cells. Conclusions: This study suggests that glycation of BLG by MR significantly alters its fate in processes involved in immunogenicity and allergenicity, pointing out the importance of food processing in food allergy."
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The quantification and identification of new plasmid-acquiring bacteria in representative mating conditions is critical to characterize the risk of horizontal gene transfer in the environment. This study aimed to quantify conjugation events resulting from manure application to soils and identify the transconjugants resulting from these events. Conjugation was quantified at multiple time points by plating and flow cytometry, and the transconjugants were recovered by fluorescence-activated cell sorting and identified by 16S rRNA sequencing. Overall, transconjugants were only observed within the first 4 days after manure application and at values close to the detection limits of this experimental system (1.00–2.49 log CFU/g of manured soil, ranging between 10–5 and 10–4 transconjugants-to-donor ratios). In the pool of recovered transconjugants, we found amplicon sequence variants (ASVs) of genera whose origin was traced to soils (Bacillus and Nocardioides) and manure (Comamonas and Rahnella). This work showed that gene transfer from fecal to soil bacteria occurred despite the less-than-optimal conditions faced by manure bacteria when transferred to soils, but these events were rare, mainly happened shortly after manure application, and the plasmid did not colonize the soil community. This study provides important information to determine the risks of AMR spread via manure application.
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Water treatment companies are more and more interested in chemical-free water treatment. This is a solution that might not only decrease costs of chemicals, but also decrease possible formation of by-products and contribute to decreasing the introduction of emerging contaminants in the environment. A possible route for this is the use of magnetic fields based treatment. Magnetic fields exist around us (our planet is surrounded by such fields) but are not broadly used in water treatment. A reason for this situation isthe fact that water treatment is a rather traditional market and magnetic treatment, conversely, a rather controversial and (still) not completely understood. Even with such resistance, recently it has been shown that magnetic fields applied to drinking water resulted in significant structural change of its microbiome [1]. This community structural change was clearly detected with a newly developed flow cytometry method, where the phenotypic characteristics of the entire microbial community could be analysed instantly [2-9]. Lab-scale batch experiments have shown that magnetic fields can selectively boost the growth of smaller bacteria [1][3] and indicated as a next step that the same principle could be addressed in pilot scale tests. ISusMag is structured to apply the robust and instant flow cytometry method to examine the effect of magnetic fields on drinking water at pilot scale under realistic field conditions. For this purpose, groundwater will be evenly distributed into two (pipe)lines of the same length: one will be magnetically treated, and one will be used as control. Samples will be taken at the end of the two pipes for flow cytometry examination. Measurement results can help drinking water companies to understand whether a magnetic treatment is an alternative to control the growth of pathogenic bacteria instead of classical chemical treatment (disinfection).
