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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Bacteriocins, Caspases, Cell Line, Cell Survival, Cytoskeleton, Deoxyribonucleases, Escherichia coli Proteins, Human Umbilical Vein Endothelial Cells, Humans, Mutagens.
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Is escherichia coli uropathogenic-specific protein , Usp , a bacteriocin-like genotoxin? Context: Bacterial genotoxins provoke DNA damage and carcinogenesis. The Escherichia coli uropathogenic-specific protein gene, usp, and its linked genes, imu1-3, are associated with strains from pyelonephritis, prostatitis, and bacteremia of urinary tract origin. While the Usp C-terminal domain exhibits similarity with DNase-like colicins and pyocins, its role and mechanisms of action, as well as those of the 3 associated proteins, is unknown. We isolated Usp and Imu1-3 and examined their activity on plasmid DNA, human umbilical vein endothelial cells, and human embryonic kidney cells (cell line HEK293). The affect of Usp and Imu1-3 was assessed by MTT and Comet assays, infection assays, caspase 3/7 activity, fluorescently labeled actin staining, and Western blotting. Usp possesses DNase activity and, particularly when coapplied with Imu2, exhibits genotoxic activity in mammalian cells. Infection assays demonstrated that E. coli usp(+) imu1-3(+) affects the viability of mammalian cells, induces increased caspase 3/7 activity, and perturbs cell cytoskeleton structure.
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Usp is a novel E. coli genotoxin active against mammalian cells. Optimal in vivo activity of Usp requires Imu2. Infection with E. coli usp(+) imu1-3(+) induces a response characteristic of apoptosis. Final Decision: yes