Geromel V, Parfait B, von Kleist-Retzow J C, Chretien D, Munnich A, Rötig A, Rustin P
Unité de Recherches sur les Handicaps Génétique de l'Enfant, INSERM U393, Hôpital des Enfants-Malades, Paris, France.
Biochem Biophys Res Commun. 1997 Jul 30;236(3):643-6. doi: 10.1006/bbrc.1997.7024.
The competition between the respiratory substrates to gain access simultaneously to the respiratory chain depends on the dehydrogenase activity, the mitochondrial ubiquinone pool, and the oxidizing activity of the cytochrome segment. By studying the co-oxidation of NADH and succinate by control human liver homogenates, we found that a change in the balance between respiratory chain complex activities may affect significantly the ability of the mitochondria to oxidize one or the other substrate. Accordingly, in the particular case of a patient presenting with a partial complex I and IV deficiency, we observed a strongly reduced ability to oxidize NADH in the presence of succinate. It therefore appeared that even a slight imbalance between respiratory chain enzyme activities may result in a full blockade of a given substrate oxidation.
呼吸底物之间同时进入呼吸链的竞争取决于脱氢酶活性、线粒体泛醌池以及细胞色素段的氧化活性。通过研究对照人肝匀浆中NADH和琥珀酸的共氧化，我们发现呼吸链复合体活性之间平衡的改变可能会显著影响线粒体氧化一种或另一种底物的能力。因此，在一名患有部分复合体I和IV缺乏症的患者的特殊情况下，我们观察到在存在琥珀酸的情况下氧化NADH的能力大幅降低。因此，即使呼吸链酶活性之间存在轻微失衡也可能导致特定底物氧化的完全阻断。
