Purification and properties of the nicotinamide–adenine dinucleotide phosphate-dependent isocitrate dehydrogenase from pig liver cytoplasm

Abstract

The NADP-dependent isocitrate dehydrogenase from pig liver soluble fraction was purified over 500-fold with an overall yield of 25%. The purified enzyme, which is homogeneous by all the usual criteria, has a molecular weight of about 75000 and is composed of two identical subunits. This has been demonstrated by ultracentrifugation, fluorescence titration and peptide ;fingerprinting'. The maximal turnover number, extinction coefficients at 280nm and 260nm and amino acid analysis are described.