Cadmium induces two waves of reactive oxygen species in Glycine max (L.) roots

Abstract

Cadmium (Cd) is a non-essential heavy metal that may be toxic or even lethal to plants as it can be easily taken up by the roots and loaded into the xylem to the leaves. Using soybean roots (Glycine max L.) DM 4800, we have analysed various parameters related to reactive oxygen metabolism and nitric oxide (NO) during a 6 day Cd exposure. A rise in H2O2 and NO, and to a lesser extent O2 ·− content was observed after 6 h exposure with a concomitant increase in lipid peroxidation and carbonyl group content. Both oxidative markers were significantly reduced after 24 h. A second, higher wave of O2 ·− production was also observed after 72 h of exposure followed by a reduction until the end of the treatment. NOX and glicolate oxidase activity might be involved in the initial Cd-induced reactive oxygen species (ROS) production and it appears that other sources may also participate. The analysis of antioxidative enzymes showed an increase in glutathione-S-transferase activity and in transcript levels and activity of enzymes involved in the ascorbate-glutathione cycle and the NADPH-generating enzymes. These results suggest that soybean is able to respond rapidly to oxidative stress imposed by Cd by improving the availability of NADPH necessary for the ascorbate-glutathione cycle.

Acquired tolerance to cadmium following long-term acclimation to CdCl2 in rice suspension cultures

“…The burst of H 2 O 2 was detected in many plants like Arabidopsis, tobacco, and soybean (De Michele et al 2009;Garnier et al 2006;Perez-Chaca et al 2014;RomeroPuertas et al 2004), thus was widely accepted as one of the fatal symptoms caused by Cd. Under our experimental conditions, the burst was also detected in the non-acclimated cells, however, was deterred in the acclimated cells.…”

“…Excessive ROS cause membrane damage, destruction of cellular organelles and biomolecules such as lipids, proteins and nucleic acids and eventually the death of the plants (Choppala et al 2014;Garnier et al 2006). Recently, ROS are emerging as signal molecules involving in the responses to biotic or abiotic stresses, rather than being just associated with toxicity (D'Autreaux and Toledano 2007; Gallego et al 2012;Perez-Chaca et al 2014). …”

Cadmium resistance mechanism in Escherichia coli P4 and its potential use to bioremediate environmental cadmium

“…Cadmium is a highly toxic, non-essential, and nonbiodegradable heavy metal (Aksoy et al 2014;Pérez-chaca et al 2014;Rahoui et al 2014;Xu et al 2014). Though it is found abundantly in earth crust and commonly associated with ores of zinc, lead, and copper (Cheng et al 2014), its increasingly high concentration in our environment is due to human activities (Maynaud et al 2014) such as mining, electroplating, stabilizing plastics, manufacturing batteries, alloy, pigment, and high phosphate fertilizers (Klaassen et al 2009;Yazdankhah et al 2010;Zeng et al 2013).…”

The Response of Duckweed (Lemna minor L.) Roots to Cd and Its Chemical Forms

“…Cd has previously been shown to induce reactive oxygen species (ROS) and cause oxidative stress (OS), which damages cell structure and function [16,17]. Plants have evolved effective scavenging mechanisms to survive the Cd stress [6].…”