Evaluation of antibacterial activity of peptide fractions derived from Iranian scorpion Hemiscorpius lepturus

Continuous appearance of antibiotic resistance bacteria can cause significant complications and mortality. In this regard, tracing for new antimicrobial agents is of great significance. During the past decades, many studies have documented isolation of Antimicrobial Peptides (AMPs) from different sources. These peptides which are responsible for hinnate immunity were purified from human, vertebrates, invertebrates, insects, venomous animals, and plants. This study aimed to extract antibacterial peptides from Iranian scorpion Hemiscorpius lepturus. Venom was obtained by electric stimulation and its quality examined by protein electrophoresis. The venom peptides were purified using Gel filtration chromatography and subsequently with Reverse Phase- High Performance Liquid Chromatography (RP-HPLC). The peptide fractions were evaluated for antibacterial activity against Pseudomonas aeruginosa ATCC 27853. Inhibitory activity was determined by disk diffusion method. Seven protein fractions were obtained from Sephadex-G50, among them only two fractions had peptides with less than 10 kDa. One FPLC purified fraction had anti-pseudomonas activity by disk diffusion method and was selected for further purification. Four major fractions were obtained by RP-HPLC ranging from 4 to 7 kDa. Subsequent tests showed that two fractions had bactericidal activity against pseudomonas. Natural compounds like antimicrobial peptides derived from venomous animals could be an effective solution to deal with multidrug-resistant pathogens. The results demonstrated that two peptide fractions of the scorpion venom had bactericidal activity against pseudomonas. This is the first report for isolation of antibacterial peptides from the Iranian scorpion Hemiscorpius lepturus.