Assessment of Genotoxicity of Marcescin Produced by Clinical Isolates of Serratia marcescens in vivo

Background: Marcescin, a proteinaceous or antimicrobial peptide produced by Serratia marcescens , is a Gram-negative bacterium, that uses ribosome synthesis to inhibit the growth of closely related and nonrelated bacterial strains. Objectives: In this research, the genotoxic effects produced by S. marcescens were identified on the bone marrow cells of male albino mice using the comet assay. Materials and Methods: S. marcescen s was isolated from samples of urine, blood, and stool from patients at the Private Nursing Home Hospital and Baghdad Teaching Hospital. The most effective marcescin producers were selected after the cup assay was used to identify which isolates produced marcescin. By inducing the productive isolates with mitomycin-C (2 μg/mL), marcescin was obtained. The well diffusion method was employed to measure marcescin activity, and the Bradford method was used to measure protein concentration. About 2.5, 5, 10, 20, 40, and 80 mg/kg of the extract were given as intraperitoneal injection to the mice for 24 h. Results: According to the results, the crude marcescin has a dose-dependent harmful effect. Damage to deoxyribonucleic acid (DNA) increased significantly ( P ≤ 0.01) with increasing doses of marcescin in comet length, head diameter, %DNA in tail, and olive tail moment, respectively. While tail length showed nonsignificant differences between control and treatment groups. Conclusion: Marcescin causes damage to DNA in bone marrow cells of albino mice, and its damage increases with increasing dose. The comet assay is appropriate for determining this.