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Clostridioides difficile (C. difficile) is an opportunistic anaerobic bacterium that causes severe diseases of the digestive tract of humans and animals. One of the possible methods of preventing C. difficile infection is to develop a vaccine. The most promising candidates for vaccine antigens are the proteins involved in the adhesion phenomena. Among them, the FliC and FliD are considered to be suitable candidates. In this paper, the FliC and FliD protein polypeptide epitopes were mapped in silico and by using PEPSCAN procedure. We identified four promising epitopes: 117QRMRTLS123, 205MSKAG209 of FliC and 226NKVAS230, 306TTKKPKD312 of FliD protein. We showed that 117QRMRTLS123 sequence is not only located in TLR5-binding and activating region, as previously shown, but forms an epitope recognized by C. difficile-infected patients' antibodies. 205MSKAG209 is a C. difficile-unique, immunogenic sequence that forms an exposed epitope on the polymerized flagella structure which makes it a suitable vaccine antigen. 226NKVAS230 and 306TTKKPKD312 are well exposed and possess potential protective properties according to VaxiJen analysis. Our results open the possibility to use these epitopes as suitable anti-C. difficile vaccine antigens. [ABSTRACT FROM AUTHOR]

Background: The aim of the current study was to investigate whether the Basidiomycetes fungus Lentinula edodes can biosynthesize Se-methyl-seleno- l-cysteine, a seleno-amino acid with strong anticancer activity, and to optimize the culture conditions for its biosynthesis. We hypothesize that preparations obtained from Se-methyl-seleno- l-cysteine-enriched mycelia from this medicinal mushroom would possess stronger cancer-preventive properties than current preparations. Results: By optimizing the concentration of selenium in the culture medium, we increased the mycelial concentration of Se-methyl-seleno- l-cysteine from essentially non-detectable levels to 120 µg/g dry weight. Significantly elevated levels of this amino acid also correlated with significant (twofold) inhibition of mycelial growth. Increases in the concentration of mycelial Se-methyl-seleno- l-cysteine appeared to be highly correlated with the enhanced biosynthesis of selenomethionine and total selenium content in mycelium. Conclusions: We have demonstrated that in L. edodes, enhanced biosynthesis of this non-protein amino acid eliminates excess selenium. [ABSTRACT FROM AUTHOR]

The paper presents investigations of the influence of chemically aggressive bio functionalization process for histidine-tagged proteins on thickness, optical and mechanical properties of silicon oxynitride (SiOxNy) film, which is often used as substrate material for a number of biosensors. We discuss the biofunctionalization effect for a set of SiOxNy films deposited by the radio frequency plasma-enhanced chemical vapour deposition method with various N2O/(SiH4+NH3) gas flow rate. It has been found that as an effect of biofunctionalization procedure, the SiOxNy films increase both their refractive index and hardness. Moreover, films deposited with higher N2O flow, which are softer and show lower refractive index, may slightly reduce their thickness as a result of the biofunctionalization process, but their surface favours more formation of on them protein biofilm than on films obtained with lower concentration of N2O. [ABSTRACT FROM AUTHOR]