The subcellular distribution and properties of XXXX dehydrogenases in @entity35 liver.

@entity2125 @entity1110 @entity1391 @entity35 @entity9955 @entity264 @entity3094
1. Kinetic experiments suggested the possible existence of at least two different @entity2125 -dependent @entity264 dehydrogenases in @entity35 liver. Distribution studies showed that one enzyme, designated enzyme I, was exclusively localized in the mitochondria and that another enzyme, designated enzyme II, was localized in both the mitochondria and the microsomal fraction. 2. A @entity1110 -dependent enzyme was also found in the mitochondria and the microsomal fraction and it is suggested that this enzyme is identical with enzyme II. 3. The K(m) for @entity3094 was apparently less than 10mum for enzyme I and 0.9-1.7mm for enzyme II. The K(m) for @entity2125 was similar for both enzymes (20-30mum). The K(m) for @entity1110 was 2-3mm and for @entity3094 0.5-0.7mm for the @entity1110 -dependent activity. 4. The @entity2125 -dependent enzymes show pH optima between 9 and 10. The highest activity was found in pyrophosphate buffer for both enzymes. In @entity1391 buffer there was a striking difference in activity between the two enzymes. Compared with the activity in @entity9955 buffer, the activity of enzyme II was uninfluenced, whereas the activity of enzyme I was very low. 5. The results are compared with those of earlier investigations on the distribution of @entity264 dehydrogenase and with the results from purified enzymes from different sources.
