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Background and Objective: Human erythropoietin (EPO) is a glycosylated hormone with molecular weight of about 40 KDa which is synthesized in kidneys and plays an important role in proliferation and differentiation of erythrocytes.This study was done to assess and analyze the expression of recombinant EPO in Leishmania tarentolae host. Method: In this descriptive study, the EPO gene was codoned , optimized with bioinformatics database prior to be synthesized. It was cleaved by KpnIandXbaI enzymes and cloned into pLEXSY expression vector. The constructed expression cassette was transfected into Leishmania tarentolae through electroporaton method. Identification and confirmation of transfected colonies was performed using PCR expression diagnostic primers and EPO specific primers. Induction of the cloned gene was done with tetracycline. The expression in induced strains was analyzed by SDS-PAGE and western blotting techniques. The amount of recombinant protein was quantified by ELISA method. Confirmation of cloning and EPO expression cassette was carried out through genetic engineering procedures. Results: Expression analysis of transfected parasitic strain with SDS-PAGE and western blotting confirmed gene integration into chromosomal of host as well as expression. The optimal conditions for expression were found to be 10μg of tetracycline and 72h induction time. Molecular weight of expressed protein estimated to be 40 KDa and expression level was determined to be 12.4 mg/l which was equal to 1% of total protein mass. Conclusion: EPO expression cassette for cloning and expression in Leishmania tarentolae was designed and protein of interest was successfully induced and identified Leishmania tarentolae can be used as a suitable host for production of recombinant EPO and this technology has a potential for localization.

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Background and Objective: Streptomyces are gram-positive and aerobic bacterial strains that are isolated from different sources. Streptomyces have the ability to produce secondary metabolites and biologically active substances and are therefore very important in the field of biocontrol. Urate oxidase is a microbial enzyme product that can be extracted from a variety of sources, including streptomycin. In the present study, cloning of the urate oxidase gene isolated from seawater streptomycosis was performed in Escherichia coli Origami bacteria.
Methods: In this descriptive study, a total of 60 water and sediment samples were collected from different depths of the Caspian Sea coast in Mazandaran province, Iran. The Geram, staining methyl red, VP, citrate, starch hydrolysis, casein hydrolysis, nitrate reduction, oxidase and catalase tests were performed to identify and isolate Streptomyces. The urate oxidase gene was cloned using the T-A cloning method using the PTG-19 vector inside the host of Escherichia coli Origami. The expression of cloned genes in recombinant colonies was investigated by Real-Time PCR. The phylogenetic tree was drawn using clustalX and Mega5 software.
Results: Screening of marine water samples identified 12 isolated streptomyces, all of which had the urate oxidase gene. The expression of urate oxidase gene in Escherichia coli Origami was confirmed by Real-Time PCR. The results of phylogenetic studies identified some close relatives of Streptomyces as candidates for subsequent studies.
Conclusion: Streptococcus bacteria can be considered as a rich source of secondary metabolites with many applications and can be used as a native to produce the enzyme urate oxidase. By using different cloning hosts and examining optimal production conditions, this strain can be a candidate for future studies to develop antimicrobial drugs and compounds.

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Background and Objective: Streptococci are Gram-positive and anaerobic bacteria that are isolated from different sources. These bacteria are capable of producing superantigens, toxins, and biologically-active substances and are therefore very important in the field of infectious disease. Streptococcal pyrogenic exotoxins A (speA) is produced by various bacteria, including Streptococcus dysgalactiae. This study aimed at the isolation, cloning, and production of speA from streptococci from the skin of psoriasis patients.
Methods: In this descriptive-laboratory study, samples were taken from 60 psoriasis patients. S. dysgalactiae isolated were identified by different tests. The speA gene was cloned by the TA cloning method using PTG-19 vector into the Escherichia coli X11 blue as host. Expression of the cloned gene in recombinant colonies was evaluated by SDS-PAGE.
Results: Screening of white recombinant colonies confirmed the presence of speA genes. Expression of the speA gene in E. coli X11 blue was confirmed by SDS-PAGE.
Conclusion: Streptococcus superantigens can be considered as a rich source of vaccine production for different infections caused by these bacteria. By utilizing different cloning hosts and investigating optimal production conditions, S. dysgalactiae could be a candidate for future studies on vaccine production.