Staphylococcal enterotoxin B, from Staphylococcus aureus (S. aureus), is one of the most potent bacterial superantigens with profound toxic effects on the immune system. It is associated with food poisoning, toxic shock, atopic dermatitis, asthma, and nasal polyps in humans. The current diagnostic methods for staphylococcal enterotoxin are mainly based on traditional monoclonal antibodies which hardly meet the requirements for clinical applications, and hybridoma clones lose their ability to secrete antibodies during time. The present study investigates the development of a novel, highly specific, low-cost, and sensitive nanobody capable of being used in immunoassays for Staphylococcal enterotoxin B (SEB) detection in suspicious foods. For this purpose, Camelus dromedarius was immunized against SEB toxin. After obtaining acceptable titration, a high-quality phage display nanobody library (4 × 10 PFU/ml) was constructed. High-affinity SEB-specific nanobodies were retrieved from constructed libraries. After phage rescue and five round of biopanning, clone screening was performed by phage ELISA. Recombinant nanobodies which were expressed from C7 and C21 clone showed the highest affinity for SEB. The presence of high quality and pure nanobody band at ~ 15 kDa was confirmed by SDS-PAGE and western blotting. The affinity constant which was measured by ELISA was calculated to be around 10 M. The results suggest that the proposed detection method by nanobodies is an alternative diagnostic tool enabling a rapid, inexpensive, and specific detection of the SEB.

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The properties of bacteriorhodopsin (BR) can be manipulated by genetic engineering. Therefore, by the methods of gene engineering, Asp85 was replaced individually by two other amino acids (D85V, D85S). The resulting recombinant proteins were assembled into soybean vesicles retinylated to form functional BR-like nano-particles. Proton translocation was almost completely abrogated by the mutant D85S, while the D85V mutant was partially active in pumping protons. Compared with wild type, maximum absorption of the mutants, D85V and D85S, were 563 and 609 nm, which illustrated 5 nm reductions (blue shift) and 41 nm increases (red shift), respectively. Since proton transport activity and spectroscopic activities of the mutants are different, a wide variety of membrane bioreactors (MBr) have been developed. Modified proteins can be utilized to produce unique photo/Electro-chromic materials and tools.

Introduction: The top 3 causes of death worldwide include heart disease, injury, and cancer; and cancer records the 2nd place as the leading cause of death in the United States of America after cardiovascular diseases and injuries. Cancer can begin and progress in a very highly twisted and complex pattern and follow the multifactorial route. There is only very few research on medicinal properties Oliveria decumbens rare and valuable plant specially on cancer. So, in this study we tried to cover all needs for future in vivo research. Methods: MTT assay has been performed to estimate the cytotoxicity of the ethanolic extract of the plant. Its free radical capacity evaluation was done by DPPH assay. Furthermore, real-time PCR, the wound-healing assay along with a DNA damage test to study DNA fragmentation characteristics. The plants transcriptomic study was performed by NGS de Novo assembly. Result: Oliveria decumbens ethanolic extract showed an Ic50 of 14.39 mu g/ml. The real-time PCR showed that Oliveria decumbens ethanolic extract significantly induced apoptosis by upregulating the bax gene and slight downregulation of bcl2 an anti-apoptosis gene. The NGS de Novo transcriptome analysis discovered 38 genes responsible for secondary metabolite synthesis so far. The remaining genes and reconstruction of the co-expression network of the transcriptome are underway. Conclusion: The outcome of the Scratch-test and DNA fragmentation confirmed the anti-metastatic and DNA damage properties respectively. Based on these findings; Oliveria decumbens ethanolic extract shall be considered as potential anticancer and chemotherapeutic agents which may elucidate in upcoming studies.