Molecular screening and cloning of the Protease encoded gene from Streptomyces strains isolated from Persian Gulf

Document Type : Research Article


1 East Tehran Branch, Islamic Azad University, Tehran, Iran

2 Department of Microbiology, School of Basic Sciences, Saveh Branch, Islamic Azad University, Saveh, Iran


Protease is an enzyme with various uses in medicine, industry and textile. One of the most important sources of protease production is bacteria such as Streptomyces. So, the aim of this study was cloning and sequencing of the protease gene in the Streptomyces spp isolated from Persian Gulf in Escherichia coli XL1blue. After collection of marine sediments from the Persian Gul, Streptomyces strains were identified using standard laboratory tests. All isolates were confirmed using 16S rRNA amplification test. Protease encoded gene were identified using specific primers in the PCR method. Protease gene was cloned in the E. coli host vector by TA cloning technique and finally the expression of the genes was measured using Real-time PCR method. ClustalX and Mega5 software were used to draw the phylogenetic tree. Twelve isolates of Streptomyces were isolated and 25% (n; 3/12) of them were positive for protease gene. After cloning of the gene, colony selection (blue / white colonies) were used for identification of success cloned strains. A relative expression of the protease gene was shown by real-time PCR test. Phylogenetic tree with the neighbor joining method show that, Streptomyces spp with bootstrap values 99% located in a clade which indicated their close relatedness. Protease enzyme production was performed by recombinant plasmid and TA cloning, and further studies could be helpful to optimize different conditions for this enzyme production. So, The Persian Gulf is a large pool for the protease producing Streptomyces for medical and industrial use.