1. 1. The separation by zonal centrifugation of two enoyl-CoA reductases located in microsomes and mitochondria of rat liver is described. 2. 2. The microsomal enzyme can use either NADH or NADPH as hydrogen donor. It shows optimal activity at pH 7.9 with trans-2,3-hexenoyl-CoA as substrate. 3. 3. The mitochondrial enzyme shows an absolute requirement for NADPH as hydrogen donor with an optimum at pH 7.7. An investigation of the chain length specifity revealed a maximum with trans-2,3-decenoyl-CoA. In contrast to the microsomal system, the enzymatic activity from mitochondria could be solubilized by treatment with acetone. 4. 4. Varying effects of both NADH and NADPH on the rate of acetyl-CoA-dependent chain elongation in crude mitochondrial preparations, reported by several groups, could be explained by varying degrees of microsomal contamination. 5. 5. A possible physiological significance of the mitochondrial system in hydrogen transport and conservation of energy is discussed.
|Original language||English (US)|
|Number of pages||13|
|Journal||Biochimica et Biophysica Acta (BBA)/Lipids and Lipid Metabolism|
|State||Published - Oct 5 1972|
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