Two Different Isocitrate Dehydrogenases from : Enzymology and Coenzyme-Evolutionary Implications.

PAO1, as an experimental model for Gram-negative bacteria, harbors two NADP-dependent isocitrate dehydrogenases (NADP-IDHs) that were evolved from its ancient counterpart NAD-IDHs. For a better understanding of PaIDH1 and PaIDH2, we cloned the genes, overexpressed them in and purified them to homogeneity. PaIDH1 displayed higher affinity to NADP and isocitrate, with lower Km values when compared to PaIDH2.