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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: Pseudomonas aeruginosa is an opportunistic pathogen that is a major cause of mortality in immunocompromised patients. One of the most important mechanisms of resistance of this bacterium is biofilm formation. The aim of this study was done to determine the Effect of Morin on Expression of Biofilm Gene of Pseudomonas aeruginosa Isolated from burn wounds by Real time PCR.
Methods: In this descriptive-analytic study 60 sample were collected from burn wounds of patients admitted to the hospitals in Tehran, Iran. Samples were identified by using biochemical methods. The DNA of the isolates was extracted and then antimicrobial activity of morin analyzed by microbroth dilution assay. The presence of biofilm production genes was investigated by PCR. Finally, the expression of lasI gene in combination with Sub-MIC concentration of morin in biofilm-producing bacteria was evaluated using Real time PCR.
Results: From 60 samples that analyzed by Multiplex-PCR, 12 (20%) Pseudomonas aeruginosa strains were isolated in which 12 isolates (100%) were carried lasI and lasR, genes, respectively. 3 isolates (25%) were carried rhlI gene. Sub-MIC concentration of morin in biofilm-producing bacteria reduced lasI gene expression in Pseudomonas aeruginosa.
Conclusion: Morin has significant efficacy on Pseudomonas aeruginosa and could be a good alternative for treatment of antibiotic resistant isolates.