- - - Department of Biology, Urmia Branch, Islamic Azad University, Urmia, Iran
- - - Department of Biology, Urmia Branch, Islamic Azad University, Urmia, Iran

Background: The study for new antibiotics is of great importance in investigating programs around the worldwide for pharmaceutical, industrial and agricultural applications. Streptomyces like filamentous soil bacteria are used as an essential biological tool for their ability to producing a wide range of new secondary metabolites such as antibiotics. Identification and isolation of new species seemed to be important in the presentation of significantly adequate antibiotics, because antibiotic resistance infectious diseases are the second leading cause of death worldwide, inducing research and development of new antibiotics. Therefore, in this study, we aimed to isolate and characterize novel strains of Streptomyces spp. with high antibiotic production ability. Methods: Soil samples were collected randomly from primitive soils of Urmia, West Azerbaijan province, from Iranin ۲۰۱۹. The isolates of Streptomyces spp. were carried out in a specific culture medium. Their primary and secondary antibacterial activity againstgram-positive bacteria Listeria monocytogenes, Bacillus cereus and Staphylococcus aureus, alsogram-negative Escherichia coli was checked out. Finally, the antibacterial properties of strains based on ۱۶S rRNA sequencing were analyzed by MEGA X software. Results: Totally, ۱۵۰ colonies were isolated from four soil collected samples. In the primary screening of ۱۰ isolates, insulated antibacterial activity and in the secondary screening, ۳ examples were selected. The microorganisms showed antibacterial activity. Sequencing of the ۱۶S rRNA gene from C-B۱-۱۲, D-D۳-۷, and C-Y۲-۲ isolates showed similarity to Streptomyces indiaensis. Conclusions: The results of this study indicated that there are new isolates in the soil samples of West Azerbaijan province that are capable of producing new antibacterial agents.

Actinomycetes, Streptomyces, Antibacterial activity, ۱۶s rRNA gene, Iran