Production of peroxynitrite in arabidopsis peroxisomes

Peroxisomes are subcellular compartments involved in multiple cellular metabolic pathways. Corpas and Barroso use fluorescent probes to study transgenic Arabidopsis thaliana and show that under conditions of no stress peroxynitrite (ONOO^–), a nitric oxide-derived molecule that causes nitration of proteins, is clearly localized in the peroxisomes of roots and stomatal guard cells. They demonstrate that cadmium causes a general increase in the production of superoxide anions and nitric oxide with a concomitant generation of peroxynitrite, suggesting that peroxisomes participate in the nitro-oxidative stress response against cadmium.