Iron (Fe3+)-mediated redox responses and amelioration of oxidative stress in cadmium (Cd2+) stressed mung bean seedlings: a biochemical and computational analysis

The present investigation aims to evaluate the possible ameliorative role of iron (Fe3+) on cadmium (Cd2+)-induced oxidative stress in mung bean (Vigna radiata L.) seedlings using biochemical and computational approaches. Imposition of Cd2+ stress for a period of 7d showed substantial changes in the growth of root and shoot, and was accompanied by significant Cd2+ accumulation and alteration of biochemical parameters. Cd2+ stress resulted in a significant reduction in root and shoot length, biomass and moisture content, and increased the levels of reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) and superoxide (O-2(center dot-)). Furthermore, a significant increase in the rate of lipid peroxidation and degradation of antioxidant defence metabolism were observed. Supplementation of the Cd2+-stressed seedlings with Fe3+ for 7d resulted in amelioration of growth, and restoration of normal cellular homeostasis as observed by considerable changes in oxidative stress parameters as compared to Cd2+ treated seedlings alone. Besides, in absence of Fe3+, Cd2+ accumulation in both root and shoot were significantly high as compared to both control and Fe3+-supplemented seedlings. Computational (molecular docking) analysis with superoxide dismutase and catalase as target enzymes revealed that both Cd2+ and Fe3+ have got affinities for the active sites of these antioxidant enzymes. Thus, it is hereby proposed that Cd2+ may potentially interfere with the activities of these antioxidant enzymes, while Fe3+ may prevent such interactions. Our findings based on biochemical and computational analysis clearly reveals the ameliorative role of Fe3+ on Cd2+-induced alterations in growth and oxidative stress in mung bean seedlings.