抄録
NADP-dependent isocitric dehydrogenase (ICD) has been found to exist in two isozymic forms in rat, human and rabbit tissues. The two isozymes differ in electrophoretic mobility and tissue and subcellular location.The isozyme predominating in heart tissue is located in the mitochondrial fraction and that predominating in liver tissue in the supernatant fraction of tissue homogenates. However, the isozyme in kidney tissue is located in the two fractions of tissue homogenates. The anomaly appears to be related with the isozyme composition of the ICD of the various organs.
Moreover, the effect on inhibition fo ICD by heat, lipase and trypsin in vatrowas also demonstrated, and the two isozymes were shown to differ in sensitivity to inhibition by heat and lipase. On the other hand, interaction of pyridoxal phosphate with ICD in vitrowas observed, and it indicated to involve formation of a Schiff base between the coenzyme and an amino group of the protein.
