Related Experiment Video
Updated: Sep 2, 2026

Application of an In vitro DNA Protection Assay to Visualize Stress Mediation Properties of the Dps Protein
Published on: May 31, 2013
Ferric nitrilotriacetate induced DNA and protein damage: inhibitory effect of a fermented papaya preparation
1Department of Molecular and Cell Biology, University of California, Berkeley 94720-3200, USA.
Abstract:
The carcinogen Fe-NTA catalyzes the hydrogen peroxide-derived production of free radicals and possibly acts through a mechanism involving oxidative stress. Fermented papaya preparation (FPP) has been reported as a natural antioxidant able to prevent lipid peroxidation in vitro and in vivo. However, little is known about the antioxidant properties of FPP regarding iron-mediated oxidative damage to DNA and proteins. In the present study FPP protected supercoiled plasmid DNA against Fe-NTA plus H2O2 induced single and double strand breaks. Similar protective effects of FPP were evident when human T-lymphocytes were challenged with Fe-NTA/H2O2 and DNA damage was determined using the Comet assay. Fe-NTA/H2O2 also induced fragmentation of bovine serum albumin (BSA) in vitro and depleted cellular GSH levels in lymphocytes. BSA fragmentation and GSH depletion were dose-dependently counteracted by FPP. EPR spin trapping studies demonstrated that antioxidant properties of FPP are related to both hydroxyl scavenging as well as iron chelating properties.
Related Concept Videos
DNA Damage can Stall the Cell Cycle
Mutagenicity and Carcinogenicity
Bioactivation and Tissue Toxicity
Spontaneous and Induced Mutations
Inhibitors of Bacterial DNA Synthesis

