Publication at Faculty of Science |
2009
Abstract
Non-photosynthetic NADP-malic enzyme EC 1.1.1.40 (NADP-ME), which could be involved in plant defence responses, was isolated from Nicotiana tabacum L. leaves. Mechanism of the enzyme reaction was studied by the initial rate method and was found out as ordered sequential one.
Furthermore regulation possibilities of purified cytosolic NADP-ME by cell metabolites were tested. Macroergic compounds (GTP, ATP and ADP) were strong inhibitors of NADP-ME; type of inhibition and inhibition constants were determined in the presence of the most effective cofactors, required by NADP-ME.
Predominantly non-competitive type of inhibitions of NADP-ME with respect to NADP+ and mixed type to L-malate were found.