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Synthesizing new chemical compounds and studying their biological applications have been important issues in scientific research. In this investigation, we synthesized and characterized ten new N-acetyl phosphoramidate compounds and explored the crystal structure of three others. Furthermore, not only were some kinetic inhibition parameters measured, like IC 50, K i, k p, K D for 7 compounds on human acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), but also their hydrophobic parameter was determined by shake-flask technique. All compounds (number 1–10) were investigated for anti-bacterial activity against three Gram-positive and three Gram-negative bacteria, while chloramphenicol was used as a standard antibiotic. In order to
The photoprotein aequorin has been widely used as a bioluminescent label in various biological and analytical techniques. Here, rigidifying flexible sites as a protein engineering approach was used to design the aequorin variants with high thermostability. Based on two simple approaches, B-factor analysis and replacement of glycine residues in α-helix, three mutations were created in the Gly14 and Glu156 positions. The studies showed that the bioluminescence activity of the G14A mutant was slightly increased, however, it was decreased for the E156N mutant. Also, the G14N mutant showed no significant changes compared to the wild type. Structural studies indicated that E156N mutation became much more flexible than the wild type, although G14
HSP70 is a powerful antiapoptotic protein that can block the extrinsic and intrinsic pathways of apoptosis. The present study describes a rapid, sensitive, and inexpensive system using luciferase as a reporter for the functional analysis of apoptotic compounds. For this approach, the co-transformation of Escherichia coli cells was performed with two expression vectors containing Hsp70 and firefly luciferase. It was found that the luciferase inactivated by heat treatment (40–46 ?C for 10 min) was approximately reactivated at room temperature and regained 70% of its initial activity before heat inactivation after 60 min. The results show that the reactivation of thermally inactivated luciferase was inhibited in living cells by
Abnormal angiogenesis is associated with various diseases such as solid tumors and metastasis, retinopathies, and rheumatoid arthritis. VEGF-A is the most important mediator of angiogenesis among all growth factors. The bioactivity of VEGF is mediated by two tyrosine kinase receptors VEGFR-1 and VEGFR-2 present on endothelial cells. VEGF signaling through VEGFR-2 is the major angiogenic pathway that leads to stimulation of endothelial cell ingrowths into the tumor. It comprised of an extracellular portion, a cytoplasmic portion, and a short transmembrane domain. The extracellular portion consists of seven Ig-like domains (D1–D7), of which the 1st to 3rd domains function as ligand-binding sites. In the present work, a soluble recombinant e
A targeted and controlled drug delivery system based on β-cyclodextrin (β-CD) for encapsulation and controlled release of hydrophobic drugs in the presence of maltogenic amylase (MAase), as a cyclodextrin-hydrolyzing enzyme, and trastuzumab antibody has been developed. In this study, the inclusion complex of curcumin (CUR), as a model anticancer compound, with β-CD was prepared and we constructed an antibody-enzyme bioconjugate (dextran mediated MAase–Trastuzumab bioconjugate) for controlled and targeted release of CUR at HER2 positive cancer cells (including SKBR3 and BT474). Immunocytochemistry analysis indicated that the MAase–Trastuzumab bioconjugate had significant binding affinities to HER2 positive cancer cells and demonstrate
Background: TGF-β isoforms play crucial roles in diverse cellular processes. Therefore, targeting and inhibiting TGF-β signaling pathway provides a potential therapeutic opportunity. TGF-β isoforms bind and bring the receptors (TβRII and TβRI) together to form a signaling complex in an ordered manner.Objectives: Herein, an antagonistic variant of TGF-β (AnTβ) has been designed and prepared to inhibit the formation of signaling complex and consequently its signaling pathway. This TGF-β homodimeric variant contains intact TβRII binding sites and blocked TβRI binding sites by substituting three peptide segments. So, AnTβ could only bind to TβRII, but prevent binding and recruitment of TβRI to form a signaling complex.Materials and
Abstract Saccharomyces cerevisiae is being used for long as a rich source of proteins, sugars, nucleotides, vitamins and minerals. Autolyzed and hydrolyzed yeast biomass has found numerous applications in the health food industry as well as livestock feeds. Here, we have compared three lysis methods for production of yeast lysates using autolysis, plasmolysis (ethyl acetate 1.5%), and enzymatic hydrolysis (Alcalase 0.2%). The efficiency of each process was compared according to soluble solid and protein contents, cell lysis monitoring, and release of intracellular materials, cell viability and microscopic analysis. Results showed that plasmolysis by ethyl acetate was found to be more efficient compared to autolysis, with a higher recovery
Background Since vascular endothelial growth factor (VEGF) is a major regulator of cancer angiogenesis, it is essential to develop a technology for its sensitive detection. Herein, we sensitized a chemiluminescence (CL) immunoassay through the combination of H 2 O 2-sensitive TGA-CdTe quantum dot (QD) as signal transduction, dextran system as a cross-linker to prepare enzyme-labeled antigen and the ultrahigh bioactivity of catalase (CAT) as reporter enzyme. Results Under the optimized experimental conditions, the CL-ELISA method can detect VEGF in the excellent linear range of 2–35000 pg mL− 1, with a detection limit (S/N= 3) of 0.5 pg mL− 1 which was approximately 10 times lower than the commercial colorimetric immunoassay. This prop
Artemin is an abundant thermostable protein in Artemia embryos and considered as a highly efficient molecular chaperone against extreme environmental stress conditions. The dynamic conformational properties of artemin appear to play a critical role in its biological activities. In this study, we have investigated the conformational transitions and functional changes of artemin under heat and oxidative stress to find some evidence of the relationship between the structure and function of artemin. The tertiary and quaternary structures of artemin have been evaluated by fluorescence measurements, protein cross-linking analysis, and dynamic light scattering. Based on the structural analysis, artemin showed irreversible substantial conformationa
The high-yield production of vascular endothelial growth factor (VEGF), as a major therapeutic target in pathological angiogenesis and diabetic wound healing, provides critical advantages for in vitro studies. In the present study, to improve the soluble production of human VEGF8–109 (receptor-binding domain (RBD) of VEGF or VEGF RBD), at first VEGF 8-109 encoded gene was expressed in SHuffle T7 E. coli. Moreover, in two steps, the protein production was optimized based on Taguchi design, by evaluating optimal levels of various induction parameters, such as cell density in induction time, temperature, inducer concentration, and media components. The results indicated that the highest amount of the protein was achieved in TB medium contain
ResultsUnder the optimized experimental conditions, the CL-ELISA method can detect VEGF in the excellent linear range of 2–35000 pg mL− 1, with a detection limit (S/N= 3) of 0.5 pg mL− 1 which was approximately 10 times lower than the commercial colorimetric immunoassay. This proposed method has been successfully applied to the clinical determination of VEGF in the human serum samples and the results illustrated the excellent correlation with the conventional ELISA method (R2= 0.997). The suitable recovery rate of the method in the serum ranged from 97–107%, with a relative standard deviation of 1.2–13.4%.
This experiment investigated the effects of different doses of Bacillus subtilis spore as a probiotic on the immune response, intestinal morphology and ileal dry matter digestibility in broiler chicks exposed to stress induced by corticosterone (CORT). Two hundred and eighty-eight one-day-old Ross 308 male broiler chicks were randomly assigned to six treatments in a completely randomized factorial design with and without CORT injection and 3 levels (0, 0.8?106, and 1.6?106 cfu/g) of B. subtilis spore supplementation. At 7 to 9 days of age (for 3 days), the chicks received one of the subcutaneous injections of CORT or corn oil (as control) at 2 mg/kg BW twice a day. The same injections were repeated at 25 to 27 days of age. Corticosterone in
Background: The immune system function depends on the coordination activity of the components of system and communications between them which leads to the formation of a complex communication network between immune cells. In this network, cytokines have an important role in the communication between immune cells through the interaction to their specific receptors. These molecules cause to cellular communications and normal function of a tissue. Reconstruction of such a complex network can be a way to provide a better understanding of cytokines’ function.Objective: Our main goal from reconstructing such a network was investigation of expressed cytokines and cytokines receptors in various lineage and tissues of immune cells and identifying
Because of the critical role of vascular endothelial growth factor (VEGF) in angiogenesis and its significantly increased serum levels in early stages of cancer, VEGF is considered an important prognostic biomarker in different cancers. Herein, the amplification power of PCR combined with phage displaying anti-VEGF VHH, a sensitive real-time immunoassay, was precisely designed based on phage display-mediated immuno-PCR (PD-IPCR) for the detection of VEGF. This system benefits from strong and specific binding of antigen and antibody in a sandwich immunosorbent assay platform using avastin (anti-VEGF monoclonal antibody) as the capture antibody. The anti-VEGF phage particles were used as both anti-VEGF agent and DNA template in the PD-IPCR. A