Hydrogen Sulfide Led to a Modification in the Structure of Mitochondrial Membrane of Epicotyls of Pea Seedlings Pisum sativum L. under Water Deficit Conditions

Abstract

The present study has been carried out to investigate changes in the structural characteristics of mitochondrial membranes isolated from epicotyls of pea seedlings of variety Nemchinovskiy 100 under the influence of different concentrations of NaHS. It was shown that treatment of pea seeds with NaHS at doses of 2∙10–4 and 5∙10–6 M resulted in the shift of thermally-induced structural transitions toward the region of lower temperatures and an increase in the microviscosity of both lipid and preprotein regions of mitochondrial membrane due to a decrease in the volume of their crystallization matrix. The presence of exogenous NaHS or endogenous hydrogen sulfide can enhance the activity of antioxidant defense enzymes and lead to accumulation of osmolytes. As a result, the microviscosity of the lipid bilayer could increase. To test this hypothesis, the effect of resveratrol, an antioxidant agent, on microviscosity of the lipid bilayer of epicotyl mitochondria of pea seedlings was investigated using normal pea seeds treated with resveratrol with or without pre-treatment with NaHS. Additionally, bioenergetic characteristics of mitochondria were studied. The results obtained confirmed that hydrogen sulfide has an effect on the structural characteristics of mitochondrial membranes through the activation of antioxidant enzymes and accumulation of osmolytes.