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Background and Aims: Cyanobacteria are considered as favorable source for new pharmaceutical compounds. To date, the majority of bioactive metabolites isolated from cyanobacteria are either polyketides (PKSs) or non-ribosomal peptides. Despite of several worldwide studies on prevalence of PKSs, none of them included the terrestrial cyanobacteria of the Lavasan. Therefore, this study aimed to detectthe PKS genes and correlation of the presence of these genes with antimicrobial compounds synthesis. Materials and Methods: Morphological and molecular identification of the terrestrial strains was performed after culture and purification. Amplification of polyketide synthase and phylogenetic trees were used for phylogenetic analysis. Nucleotide and protein sequences were deposited in GenBank. Lastly, to show the correlation of this gene with antimicrobial compounds synthesis, antibiogram bioassay was used. Results: Phylogentic analysis revealed that most of the identified 16SrRNA genes and PKS domains had more than 90% similarity to their closest matches in the Gen-Bank. In addition, antibiogram assessment showedthe different pattern of inhibition, indicating the involvement of variety antimicrobial substances. Conclusions: According to the results of this sudy, it seems the antibiogram bioassay and molecular detection of polyketide synthase genes are useful techniques for the assessment of productive species of natural products and the possible role of polyketide synthase enzyme complexes in the biosynthesis of biologically active compounds. [ABSTRACT FROM AUTHOR]

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Introduction: Cervical cancer is the leading cause of morbidity and cancer mortality in women throughout the world and persistent infection with human papillomavirus (HPV) is the main etiology for the development of this cancer. Peptide vaccines derived from E6 and E7 oncogenes are promising candidates for HPV vaccine production due to their safety, high stability, and ease of production. In the current study, expression strains such as Escherichia coli BL21 (DE3), BL21 (DE3)-AI, Rosetta, C41 (DE3), and BL21 (DE3)-pLysS were applied for poly epitopic E6 expression and the effects of temperature, induction time, and inducer concentration on the expression level of recombinant HPV16-E6 polypeptide protein were examined in the mentioned strains. Materials and Methods: In the present study, the optimized gene of E6 recombinant protein was cloned into pET28a vector under the control of T7 promoter and the resulting plasmid was successfully transformed into Escherichia coli strains BL21 (DE3), BL21 (DE3)-AI, Rosetta, C41 (DE3), and BL21 (DE3)-pLysS. Then, the ability of these strains to express the desired recombinant protein in different conditions was compared. Two temperatures of 25 ° C and 37 ° C, IPTG concentrations between 0.1 and 1.0 mM, and different incubation times were selected to examine the expression level of recombinant E6 protein in these strains. Results: The highest level of expression was obtained in Escherichia coli BL21 (DE3) -AI strain inducing at Optical Density (OD) of 0.9, 0.1 mM IPTG, and 16 hours induction at 25 °C. Discussion and Conclusion: The results of this study can be used to produce E6 protein as a vaccine candidate in the treatment of HPV-related cancers. [ABSTRACT FROM AUTHOR]

In this Study, the egg white fish (Rutilus frisii kutum) hydrolyzed protein was produced. Hydrolysis was performed by alcalase enzyme in 60, 120, 180, and 240 minutes and their effects on degree of hydrolysation were evaluated. The results showed that the highest degree of hydrolysis was obtained in 240 minutes. Then, in order to separate peptides, based on their molecular weights, Millipore ultra filters (3, 10 and 30 KDa) were used. The antioxidant properties of hydrolyzed protein and peptide fractions 3, 10 and 30 KDa were measured, which can compete well with synthetic antioxidants such as BHT. Four antioxidant tests including DPPH, ABTS, Ferric reducing antioxidant power (FRAP) and Ferrous (Fe2+) ion chelating ability were evaluated. In three antioxidant tests DPPH, ABTS and chelation of iron ions at a concentration of 5 mg, the highest percentage of inhibitory was observed in the treatment of hydrolyzed protein 78, 92 and 69, respectively. In the antioxidant test, fraction reduction of iron ions less than 3 kDa showed the highest absorption (1.25) at a concentration of 4 mg. [ABSTRACT FROM AUTHOR]

Background and Aim recombinant DNA technique is a powerful and appropriate method for the production of protein biopolymers with specificity in amino acid sequence and spatial chemistry. Elastin-Like Polypeptide (ELP) is a biocompatible, biodegradable and non-immunological biopolymer used in various biotechnology studies. The ELP tag is a cheap, fast and non-chromatographic technique for purifying target proteins. In this study, pET expression vector was designed for the combination of ELP gene sequences and target recombinant protein in order to produce recombinant fusion protein with the ELP tag. Methods & Materials MOD gene was transformed to E. coli-BL21 (DE3) cells after designing and synthesis among the XbaI and XhoI restriction sites in the pET-32a (+) vector of the clone. Then, colonies were isolated based on plasmid size and examined by cutting using restriction enzymes. The final recombinant colonies was verified using polymerase chain reaction method and DNA sequencing. Ethical Considerations The Research Ethics Committee of Arak University of Medical Sciences approved all ethical considerations ofworking on laboratory animals (Code: 92-146-11). Results Replacing the MOD sequence in the pET-32a vector (+) eliminated the components expressing the fusion tags (Thioredoxin, Histidine, and S-tag), the identification site of protease enzyme (tobacco etch virus), and multiple cloning site. In addition, it added specific restriction enzyme identification sequences of ELP gene and target gene. As a result, in the optimized pET-MODvector, 466 nucleotides reduced in size and the secondary structure was improved. Conclusion Considering the improvement of spatial structure and reduction of pET-MOD vector size, as well as the possibility of the fusion of recombinant protein with the ELP tag, it is possible to use this vector for ELPyation of the target protein. [ABSTRACT FROM AUTHOR]

Cancer is one of the leading causes of death worldwide. Thus, it is important to find newer, more selective, and more effective therapies for this disease. One of these methods that have attracted many researchers is using anticancer peptides regarding their specificity, lower side effects, and higher effectiveness on the cancer cells. One type of anticancer peptides is antimicrobial peptides. Although they have already been studied and introduced as potential agents to fight infectious diseases, only recently they have been used as a new way of cancer treatment. For decades, antimicrobial peptides have been considered a component of the native immune system; however, they can also be used as anticancer peptides due to their mechanisms and properties. This new therapeutic approach can provide a promising pathway for optimal cancer treatment with fewer side effect. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most common type of dementia in the elderly. The neuropathology and treatment of AD is not precisely determined yet, but according to the pathological studies, AD is associated with presence of toxic soluble oligomers and insoluble senile plaques formed by amyloidosis of Amyloid Beta (Aβ) in neocortical region of brain. The V10HHQKLVFFAE22 is a critical region of Aβ42 which facilitates aggregation process. An attractive therapeutic approach to treat AD is to identify small ligands that are capable of binding to critical residues in order to inhibit or reverse Aβ amyloidosis process as source of neurotoxicity. In this area, therapeutic efforts designed various organic agents and most of them focused on the N- terminal sequence of Aβ. Here, a peptide inhibitor derived from the C-terminal of Aβ (G33LMVG37) is utilized as inhibitor and combined Docking and Molecular dynamics simulation used to find the binding sights in the critical region (V10HHQKLVFFAE22). The simulation identified tree stable sites for process of penta peptide binding to Aβ42 as an inhibitor. This result indicate that this penta-peptide is capable to inhibit aggregation process and can be consider as an AD drug for preclinical studies. [ABSTRACT FROM AUTHOR]