Hydrogen Sulfide Caused a Modification in the Structure of Mitochondrial Membranes of Epicotyls of Pea Pisum sativum L. Seedlings under Water Stress

The change in the structural characteristics of mitochondrial membranes isolated from epicotyls of Nemchinovsky 100 pea seedlings under the effect of sodium hydrosulfide at various concentrations has been studied. It was shown that seed treatment with sodium hydrosulfide solution at doses of 2 × 10^–4 M and 5 × 10^–6 M caused a shift of thermally induced structural transitions in mitochondrial membranes to lower temperatures and to an increase in the microviscosity of both lipid and protein regions of mitochondrial membranes with a decrease in their crystallinity. The presence of exogenous NaHS, as well as endogenous hydrogen sulfide, could increase the activity of antioxidant defense enzymes and caused the accumulation of osmolytes. As a result, the microviscosity of the lipid bilayer could increase. To test this hypothesis, the effect of the antioxidant resveratrol on the microviscosity of the mitochondrial lipid bilayer of epicotyles of pea seedlings was studied with both untreated and pretreated with NaHS seeds. The bioenergetic characteristics of mitochondria were also studied. Data have been obtained that confirm the effect of hydrogen sulfide on the structural characteristics of mitochondrial membranes by activating enzymes of antioxidant protection and accumulation of osmolytes.