Functioning of malate dehydrogenase system in mesophyll and bundle sheath cells of maize leaves under salt stress conditions

The formation of adaptive response to salt stress in mesophyll and bundle sheath cells of maize (Zea mays L.) leaves was studied at the level of operation of enzyme systems that participate in oxidation of malate. Functioning of four malate dehydrogenases (MDH), the components of this system, was studied and found to maintain malate and pyruvate pools, which are required for operation of the Hatch-Slack cycle and actively used for neutralization of salt treatment. The increase in activity of NAD-MDH was related to salt-induced synthesis of the additional isoform of MDH in mesophyll cells. Such changes in the isozyme pattern were not found in bundle sheath cells.