Reactive oxygen/nitrogen species and antioxidants in legume nodules

Abstract

Reactive oxygen species (ROS), such as the superoxide radical and H202, are generated in legume root nodules as a result of respiration, nitrogen fixation, and other metabolic processes involving electron transfer (1). Sirnilarly, reactive nitrogen species (RNS), such as nitric oxide (NO) and nitrosoglutathione (GSNO), are produced by enzymatic and nonenzymatic mechanisms (2). Both ROS and RNS perform useful functions in redox and stress signaling and in growth and Reactive oxygen species (ROS), such as the superoxide radical and H202, are generated in legume root nodules as a result of respiration, nitrogen fixation, and other metabolic processes involving electron transfer (1). Sirnilarly, reactive nitrogen species (RNS), such as nitric oxide (NO) and nitrosoglutathione (GSNO), are produced by enzymatic and nonenzymatic mechanisms (2). Both ROS and RNS perform useful functions in redox and stress signaling and in growth and mechanisms (2). Both ROS and RNS perform useful functions in redox arid stress signalíng and in qrowth aid developmental processes when their concentrations are tiqhtly regulated by antioxidants; otherwise, ROS and RNS are potentially toxic and can give rice co oxidative and nitrosative stress, respectively (3).

In this presentation, I will give an ovewiew of the ROSIRNS and antioxidant network of nodules, and will present recent results using Lotus japonicus as a modal legume.