Iron-Sulfur-Nitrosyl Complex Increases the Resistance of Pea Seedling to Water Deficiency

The binding of free iron ions in the composition of nitrosyl complexes is probably one of the mechanisms of the antioxidant action of nitric oxide. The study of the protective properties of nitric oxide is often carried out using exogenous NO donors. In our work, we used nitric oxide donor - sodium μ2-dithiosulfate-tetranitosyldiferrate tetrahydrate (TNIC-thio). The aim of our work was to investigate the possibility of using TNIC-thio to increase the resistance of plants to stress factors. Since the implementation of anti-stress programs requires a lot of energy expenditure, we studied the functional state of the mitochondria of pea seedlings under conditions of water deficiency and treatment with TNIC-thio. The functional state of the mitochondria was studied as per the level of lipid peroxidation by the spectrofluorimetry, by a fatty acid composition of mitochondrial membranes with the chromatography technique and by the morphology of mitochondria with the atomic force microscopy. Water deficiency has caused changes in the Fatty Acid (FA) composition, which manifested themselves in increasing the content of saturated FAs and decreasing the content of unsaturated FAs containing 18 and 20 carbon atoms. Treatment of pea seeds with 10–8 M TNIC-thio under these conditions led to the prevention of LPO, prevention of changes in the FA composition of mitochondrial membranes and reduction in the number of swollen organelles. It can be assumed that the protective effect of TNIC-thio is due to the preservation of the functional state of the mitochondria.