Department of Biochemistry (2013 - Present)
biochemistry
, Tarbiat Modares University,
Biology - Biochemistry
, Al-Zahra University / QA /,
Biology - Cellular and molecular sciences
, University of Tehran, Iran
Platelets, with hemostasis and thrombosis activities, are one of the key components in the blood circulation. As a guard, they rapidly respond to any abnormal blood vessel injury signal and release their granules' contents, which induce their adhesion and aggregation on wound site for hemostasis. Recently, increasing evidence has indicated that platelets are critically involved in the growth and metastasis of cancer cells by releasing a variety of cytokines and chemokines to stimulate cancer cell proliferation and various angiogenic regulators to accelerate tumor angiogenesis. Platelets also secrete active transforming growth factor beta (TGF‐β) to promote the epithelial–mesenchymal transition of cancer cells and their extravasation f
Carboxypeptidase G2 is a bacterial enzyme that catalyzes methotrexate conversion to its inactive forms which are then eliminated via a non-renal pathway in patients with renal disorders during a high-dose methotrexate administration. Due to the increasing demand of this enzyme, it was of interest to simplify its production process. For this reason, we developed a method for production and one-step purification of this enzyme using an intein-mediated system with a chitin-binding affinity tag. The carboxypeptidase G2 gene from Pseudomonas RS16 was optimized, synthesized, cloned into the pTXB1 expression vector and finally transformed into Escherichia coli BL21 (DE3) cells. The optimal condition for the enzyme soluble expression was achieved i
Background and objectives: Urease, that catalyzes the hydrolysis of urea, has received substantial attention for its impact on living organisms’ health and human life quality. Urease inhibitors play important role in management of different diseases including gastritis and other gastrointestinal disorders. In the present study, a new surface plasmon resonance-based biosensor was designed to discover new urease inhibitors. Methods: The biosensor surface was prepared by the covalent immobilization of urease on carboxymethyldextran hydrogel (CMD 500D) via its primary amine groups. Results: The biosensor combined with an orthogonal enzyme inhibition assay was utilized for screening of 40 traditional medicinal plant extracts against Jack-bean
Herein proteomic profiling of the rat hippocampus from the kindling and pilocarpine models of epilepsy was performed to achieve new potential targets for treating epileptic seizures. A total of 144 differently expressed proteins in both left and right hippocampi by two-dimensional electrophoresis coupled to matrix-assisted laser desorption-mass spectrometry were identified across the rat models of epilepsy. Based on network analysis, the majority of differentially expressed proteins were associated with Ca 2+ homeostasis. Changes in ADP-ribosyl cyclase (ADPRC), lysophosphatidic acid receptor 3 (LPAR3), calreticulin, ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1), synaptosomal nerve-associated protein 25 (SNAP 25) and transgelin 3 protein
In spite of long-term intensive scientific research efforts, there are still many issues concerning the mechanisms of epileptogenesis and epilepsy to be resolved. Temporal lobe, in particular hippocampus, is vulnerable to epileptogenic process. Herein, electrical kindling model of temporal lobe were analyzed using proteomic approach. A dramatic decrease in nicotinamide adenine dinucleotide (NAD+) level was exhibited during the kindling procedure in hippocampus. After stage 3, high CD38 expression was detected by qPCR, nano-liquid chromatography-tandem mass spectrometry (nano-LC-MS/MS) and western blot analysis. An increase in expression of CD38/NADase activity was observed during the kindling procedure in hippocampus that represent it as on
The bacterial enzyme chondroitinase ABC, which digests extracellular chondroitin sulfate proteoglycans, has been shown to enhance axonal regeneration. However, the utilization of this enzyme as therapeutics is notably restricted due to its thermal instability. Therefore, red luminescent porous silicon that hold promise for potential applications in biological/medical imaging was used as a carrying matrix for chondroitinase with the aim of enhancing its stability. Porous Si nanoparticles were prepared by electrochemical etching of silicon wafers in ethanolic HF solution. The size of nanoparticles (210 nm) and the mean pore diameter (8 −20 nm) were determined using dynamic light scattering and scanning electron microscopy. Purified chon
Purpose The present study sought to design a multi‐functional fusion peptide with hydroxyapatite (HA) binding domain (HABD) and heparin binding domain (HBD). Methods The 74 amino acid fusion peptide contained N‐terminus of the fibrinogen β chain (β 15–66), double G4S‐linker and 12 residues with HA affinity. This construct was designed, synthesized and cloned into pET21a(+) vector and expressed in E. coli. Results HABD facilitated purification of the fusion peptide by HA affinity chromatography. Kinetic peptide binding and release on HA scaffold showed sustained release of peptide for up to 16 days. Competitive ELISA and intrinsic fluorescence assays were applied to determine HBD affinity to bone morphogenetic protein‐2 (
Removal of chondroitin sulfate proteoglycans (CSPGs) with chondroitinase ABC I (ChABC) facilitates axonal plasticity, axonal regeneration and remyelination, following injury to the central nervous system (CNS). However, the ChABC rapidly undergoes thermal inactivity and needs to be injected repeatedly. Here this limitation was overcame by immobilizing the ChABC on porous silicon (PSi) nanoparticles (ChABC@PSi). The efficacy of immobilized ChABC on CSPGs level and the demyelination insult was assessed in mice corpora callosa demyelinated by 6?weeks cuprizone (CPZ) feeding. ChABC@PSi was able to reduce the amount of CSPGs two weeks after animals treatment. CSPGs digestion by ChABC@PSi reduced the extent of demyelinated area as well as the ast
α-Synuclein fibrillation is now regarded as a major pathogenic process in Parkinson’s disease and its proteinaceous deposits are also detected in other neurological disorders including Alzheimer's disease. Therefore anti-amyloidegenic compounds may delay or prevent the progression of synucleinopathies disease. Molecular chaperones are group of proteins which mediate correct folding of proteins by preventing unsuitable interactions which may lead to aggregation. The objective of this study was to investigate the anti-amyloidogenic effect of molecular chaperone artemin on α-synuclein. As the concentration of artemin was increased up to 4?μg/ml, a decrease in fibril formation of α-synuclein was observed using thioflavin T (ThT) fluoresce
Pseudomonas aeruginosa is a unique microorganism among the antibiotic-resistant microbial pathogens. Among the various therapeutic approaches, antimicrobial peptides are effective to combat this infection. The chimera C3 is a peptide derived from the human beta-defensins 2 and 3 that has previously displayed antibacterial activity against the Gram-negative and Gram-positive bacteria. In this research, the antibacterial activity and the effect of a new genetically designed chimera C3 (i.e. chimera C3-3) on the bacterial membrane was assessed by molecular dynamics (MD) simulation. To investigate the interactions of the peptide with the lipid bilayer model and their effects on each other, the characterizations e.g. Area Per Lipid (APL), densi
Evaluation of changes expression of D1 mGluR1 and CD38 genes after electrical kindling and treatment with low-frequency stimulation in rat-Tarbiat Modares University Journals System-Modares Journal of Biotechnology
Fibrinogen is a major component of the coagulation cascade following tissue damage and rapidly forms an insoluble fibrin scaffold. Fibrin is a filamentous biopolymer that naturally forms from fibrinogen polymerization during blood clotting. After tissue damage and coagulation cascade initiation, soluble fibrinogen polymerization by thrombin enzyme begins and forms an insoluble fibrin network and blood clots with platelets. This fibrin network is crucial for the development of homeostasis after tissue damage. This biopolymer also plays a key role in wound healing as a temporary scaffold and due to its unique structural properties and physiological function, it is used in reconstructive medicine. Fibrin is able to absorb extracellular matrix
DNA replication is spatially and temporally regulated during S phase to execute efficient and coordinated duplication of entire genome. Various epigenomic mechanisms operate to regulate the timing and locations of replication. Among them, Rif1 plays a major role to shape the “replication domains” that dictate which segments of the genome are replicated when and where in the nuclei. Rif1 achieves this task by generating higher-order chromatin architecture near nuclear membrane and by recruiting a protein phosphatase. Rif1 is a G4 binding protein, and G4 binding activity of Rif1 is essential for replication timing regulation in fission yeast. In this article, we first summarize strategies by which cells regulate their replication
Background: Methotrexate is one of the most widely used chemotherapeutic agents that may cause kidney failure as a side effect. Carboxypeptidase G2 (Glucarpidase marketed under the brand name of Voraxaze) is a bacterial enzyme that can convert methotrexate to its inactive metabolites and provides an alternative non-renal pathway for methotrexate elimination in patients with renal dysfunction during high-dose methotrexate treatment. Methods: In this research, carboxypeptidase G2 was synthetized in pUC 57 vector. Then it was subcloned into pET28a between NdeI and XhoI restriction sites. Recombinant vector was transformed into E. coli BL21 and its expression was examined in various conditions.Results: The optimum expression of recombinant prot
Background: Methotrexate is one of the most widely used chemotherapeutic agents that may cause kidney failure as a side effect. Carboxypeptidase G2 (Glucarpidase marketed under the brand name of Voraxaze) is a bacterial enzyme that can convert methotrexate to its inactive metabolites and provides an alternative non-renal pathway for methotrexate elimination in patients with renal dysfunction during high-dose methotrexate treatment.Methods: In this research, carboxypeptidase G2 was synthetized in pUC 57 vector. Then it was subcloned into pET28a between NdeI and XhoI restriction sites. Recombinant vector was transformed into E. coli BL21 and its expression was examined in various conditions.Results: The optimum expression of recombinant prote
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