Nitric Oxide Associated Protein (NOA) in Pea (Pisum sativum L.)

Nitric oxide synthase (NOS) activity was detected in pea leaf extracts using citrulline formation assay. Total protein extraction method was modified based on biochemical activities such as the use of protease inhibitors, pH and precipitation with salts and organic solvents. Physiological aspects such as the effects of various chemicals that induce systemic resistance in plants on NOS activity and immunodetection of a NOS-like protein were also studied. The NOS-like protein was partially isolated using liquid chromatography and characterized based on mammalian NOS inhibitor and co-factor requirement. Correlation of NOS activity and NOS-like gene expression during pea-bacterial interactions were investigated using Ralstonia solanacearum and Pseudomonas syringae pv pisi. NOS activity was detected using citruline formation assay. Gene expression was measured using real-time reverse transcription-polymerase chain reactions (RT-PCR) and a 348-bp probe designed from a cloned cDNA fragment of pea that was homologous to NOS of snail and AtNOS1/AtNOA1 of Arabidopsis. The possibility of NO production from various sources in the cells of pea was also discussed.