BIOCHEMICAL CHARACTERISTIC OF SOLUBLE LECTINS IN CORN UNDER THE IMPACT OF WATER DEFICIT AND HYPERTHERMIA

Introduction. Drought and high temperature are two of the key factors of the environment limiting crop capacity of grains. Response of the plants to drought and high temperature is very complex and includes interaction between various molecular, physiological and biochemical processes. Synthesis of a number of proteins present under normal conditions, including lectins, increases along with synthesis of stress proteins under adverse conditions.Aim. The goal of our study is to identify the changes in the activity and biochemical characteristics of soluble lectins in maize seedlings with different drought tolerance under water and heat stress in order to create new biochemical methods for assessing drought tolerance.Methods. Three-day young sprouts of corn lines (Zea mays L.) with different levels of drought tolerance were used in the research: drought-tolerant lines Od 329, IK107 zM, non-drought tolerant lines GK 26, IK107VS3 / 66. Lectin activity was defined on the basis of their ability to agglutinate trypsinized erythrocytes of white rats. Electrophoresis was performed in 10 % PAGE following the Laemmli method.Results. The study enabled us to identify increase in soluble lectin activity (244-281 % of the reference value) under the given stress factors in drought-tolerant lines, and decrease in soluble lectin activity (39 - 79 % of reference value) under the given stress factors in non-drought-tolerant lines. Soluble lectins were isolated and purifid using salting out with ammonium sulfate, dialysis and affiity chromatography. The molecular weight of the isolated soluble lectins is in the range of 50-60 kDa. The isolated lectins had a high affiity for N-acetylglucosamine and D-fructose-6-phosphate.Conclusion. Therefore, it has been established that corn lines with positively different levels of drought tolerance are characterized by varying activity of soluble lectins.