Antimicrobial Activity of Ten Local Actinobacterial Strains against ESKAPE, Bacillus subtilis and Pseudomonas baetica Pathogens

Maryam Hazim Abduljaba *

Department of Biology, College of Science, University of Mosul, Iraq.

Talal Sabhan Salih

Department of Medical Physics, College of Science, University of Mosul, Iraq.

*Author to whom correspondence should be addressed.


Aims: The study included the isolation, purification, cultural characteristics, antimicrobial activities and molecular identification of local actinobacterial strains isolated from different locations north of Iraq.

Methodology: Oligotrophic medium supplemented with the antifungals cycloheximide (50 mg/l) and nystatin (30 mg/l) was used for preliminary isolation. ISP-3 medium was chosen as a potential medium for subsequent purification of actinobacterial strains. The cultural characteristics of all isolated actinobacterial strains were elucidated on International Streptomyces Project media (ISP2-ISP-7). 16S rRNA marker gene was used for molecular identification using 27F and 1492R universal primers.

Results: Ten isolates were biologically active against tested ESKAPE, Bacillus subtilis and pseudomonas paetica pathogens when cultured on different ISPs media under the OSMAC approach. Six representative isolates that exhibited antimicrobial activity against all or almost tested bacteria were sequenced using 16S rRNA gene. The sequences were compared with those of other actinobacterial strains that are found in Genebank database to find the best similarity and the close reference strains to our isolates. Five of the sequenced strains have been identified as Streptomyces species; MT5, MT8, MT12, MT23 and MT26 and one was identified as a rare actinobacterial strain Lentzea sp.; MT4. Nucleotide sequences have been provided and deposited in the National Center for Biotechnology Information NCBI under the accession numbers ON514131, ON514133, ON514134, ON514135, ON514136 and ON514130 respectively.

Keywords: Actinobacteria, antimicrobial activities, ESKAPE pathogens, streptomyces spp, 16S rRNA

How to Cite

Abduljaba, M. H., & Salih, T. S. (2022). Antimicrobial Activity of Ten Local Actinobacterial Strains against ESKAPE, Bacillus subtilis and Pseudomonas baetica Pathogens. South Asian Journal of Research in Microbiology, 13(4), 1–10.


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O'Neill J. Tackling drug-resistant infections globally: final report and recommendations; 2016.

Accessed 5 August 2022.


Centers for Disease Control and Prevention. Antibiotic resistance threats in the United States, 2013. Centers for Disease Control and Prevention, US Department of Health and Human Services, Atlanta, GA; 2013.

Accessed 12 September 2022.

Available: https://www. cdc. gov/drugresistance/threat-report-2013/pdf/arthreats-2013-508. pdf

Monserrat-Martinez A, Gambin, Y, Sierecki, E. Thinking outside the bug: molecular targets and strategies to overcome antibiotic resistance. International Journal of Molecular Sciences. 2019;20(6):12-20.

Cillóniz C, Dominedò C, Torres A. Multidrug resistant gram-negative bacteria in community-acquired pneumonia. Annual Update in Intensive Care and Emergency Medicine 2019. 2019;459-475.

Wang Z, Koirala B, Hernandez Y, Zimmerman M, Park S, Perlin DS, Brady SF. A naturally inspired antibiotic to target multidrug-resistant pathogens. Nature. 2022;601(7894):606-611.

Cook MA, Wright GD. The past, present, and future of antibiotics. Science Translational Medicine. 2022;14(657): eabo7793.

Azman AS, Othman I, Velu SS, Chan KG, Lee LH. Mangrove rare actinobacteria: Taxonomy, natural compound, and discovery of bioactivity. Frontiers in microbiology. 2015;6:85-96.

Selim MS, Abdelhamid SA, Mohamed SS. Secondary metabolites and biodiversity of actinomycetes. Journal of Genetic Engineering and Biotechnology. 2021; 19(1):1-13.

Tan LT, Chan KG, Pusparajah P, Yin WF, Khan TM, Lee LH, Goh BH. Mangrove derived Streptomyces sp. MUM265 as a potential source of antioxidant and anticolon-cancer agents. BMC microbiology. 2019;19(1):1-16.

Bérdy J. Thoughts and facts about antibiotics: Where we are now and where we are heading. The Journal of antibiotics. 2012;65(8):385-395.

van Bergeijk DA, Terlouw BR, Medema MH, van Wezel GP. Ecology and genomics of Actinobacteria: new concepts for natural product discovery. Nature Reviews Microbiology. 2020;18(10):546-558.

Aminov RI. A brief history of the antibiotic era: lessons learned and challenges for the future. Frontiers in microbiology. 2010; 1:34-39.

Waksman SA, Woodruff HB. Bacteriostatic and bactericidal substances produced by a soil Actinomyces. Proceedings of the society for Experimental Biology and Medicine. 1940;45(2):609-614.

Takahashi Y, Nakashima T. Actinomycetes, an inexhaustible source of naturally occurring antibiotics. Antibiotics. 2018;7(2):45-52.

Amin DH, Abdallah NA, Abolmaaty A, Tolba S, Wellington EM. Microbiological and molecular insights on rare Actinobacteria harboring bioactive prospective. Bulletin of the National Research Centre. 2020;44(1):1-12.

Terra L, Dyson PJ, Hitchings MD, Thomas L, Abdelhameed A, Banat IM, Quinn GA. A novel alkaliphilic Streptomyces inhibits ESKAPE pathogens. Frontiers in microbiology. 2018;24:58-64.

Quinn GA, Banat AM, Abdelhameed AM, Banat IM. Streptomyces from traditional medicine: Sources of new innovations in antibiotic discovery. Journal of Medical Microbiology. 2020;69(8):1040-1049.

Van Norman GA. Drugs, devices, and the FDA: part 1: An overview of approval processes for drugs. JACC: Basic to Translational Science. 2016;1(3): 170-179.

DiMasi JA, Grabowski HG, Hansen RW. Innovation in the pharmaceutical industry: New estimates of R&D costs. Journal of health economics. 2016;47:20-33.

Shirling EB, Gottlieb D. Methods for characterization of Streptomyces species. International Journal of Systematic Bacteriology. 1966;16:313-340.

Shirling EB, Gottlieb D. Cooperative description of type strains of streptomyces. International Journal of Systematic Bacteriology. 1972;22:265-394.

Chun J, Goodfellow M. A phylogenetic analysis of the genus Nocardia with 16S rRNA gene sequences. International Journal of Systematic and Evolutionary Microbiology. 1995;45(2):240-245.

Altschul P, Gish W, Miller W, Myers E, Lipman D. Basic local alignment search tool. J. Mol. Biol. 1990;215:403-410.

Rajeswari P, Jose PA, Amiya R, Jebakumar SR. Characterization of saltern based Streptomyces sp. and statistical media optimization for its improved antibacterial activity. Frontiers in Microbiology. 2015; 5:75-87.

Paudel D, Dhungana B, Caffe M, Krishnan P. A review of health-beneficial properties of oats. Foods. 2021;10(11):25-35.

Balouiri M, Sadiki M, Ibnsouda SK. Methods for in vitro evaluating antimicrobial activity: A review. Journal of pharmaceutical analysis. 2016;6(2):71-79.

Stan D, Enciu AM, Mateescu AL, Ion AC, Brezeanu AC, Stan D, Tanase C. Natural compounds with antimicrobial and antiviral effect and nanocarriers used for their transportation. Frontiers in Pharmacology. 2021;24:82-89.

May KL, Grabowicz M. The bacterial outer membrane is an evolving antibiotic barrier. Proceedings of the National Academy of Sciences. 2018;115(36):8852-8854.

Zhang YB, Liu XY, Jiang PP, Li WD, Wang YF. Mechanism and antibacterial activity of cinnamaldehyde against Escherichia coli and Staphylococcus aureus. Mod. Food Sci. Technol. 2015;31:31-35.

Romano S, Jackson SA, Patry S, Dobson AD. Extending the “one strain many compounds”(OSMAC) principle to marine microorganisms. Marine drugs. 2018; 16(7):244-252.

Rateb ME, Houssen WE, Harrison WT, Deng H, Okoro CK, Asenjo JA, Jaspars M. Diverse metabolic profiles of a streptomyces strain isolated from a hyper-arid environment. Journal of natural products. 2011;74(9): 1965-1971.

Liu T, Ren Z, Chunyu WX, Li GD, Chen X, Zhang ZT, Yin M. Exploration of diverse secondary metabolites from streptomyces sp. YINM00001, Using Genome Mining and One Strain Many Compounds Approach. Frontiers in microbiology. 2022; 13:831174-831174.

Stackebrandt E, Rainey FA, Ward-Rainey N. Proposal for a new hierarchic classification system, Actinobacteria classis nov. International Journal of Systematic and Evolutionary Microbiology. 1997;47(2):479-491.

Varghese NJ, Mukherjee S, Ivanova N, Konstantinidis KT, Mavrommatis K, Kyrpides NC, Pati, A. Microbial species delineation using whole genome sequences. Nucleic acids research. 2015; 43(14):6761-6771.

Tortoli E. The new bacterial species description: The genus Mycobacterium as an example. Revista Pan-Amazônica de Saúde. 2017;8(4):2-12.