Takamiya S, Yu Y, Cavaleante M E, Murayama K, Taka H, Tateno S, Takeuchi T, Aoki T
Department of Parasitology, Juntendo University School of Medicine, Tokyo, Japan.
Mol Biochem Parasitol. 1996 Jul;79(1):61-70. doi: 10.1016/0166-6851(96)02650-3.
Mitochondrial cytochrome c was isolated at high purity from adult Ascaris suum muscle and its molecular properties were investigated. The molecular weight of A. suum cytochrome c was determined to be 13,119 by electrospray ionization mass spectrometry. The oxidation-reduction potential of nematode cytochrome c was measured to be +248 mV; this value is comparable to those for cytochrome c from mammalian sources. The A. suum cytochrome c, like bovine heart cytochrome c, showed biphasic kinetics against bovine heart cytochrome c oxidase. Comparative kinetic studies revealed species-specificity in the reaction between cytochrome c and cytochrome c oxidase from A. suum and bovine sources. The cytochrome c content in mitochondria was highest at the second larval stage, in which the respiratory chain is the most aerobic among various developmental stages of A. suum. These data clearly show that adult A. suum cytochrome c, as isolated, is a bona fide substrate for cytochrome c oxidase in the aerobic respiratory chain of second-stage larvae.
从成年猪蛔虫肌肉中以高纯度分离出线粒体细胞色素c，并对其分子特性进行了研究。通过电喷雾电离质谱法测定猪蛔虫细胞色素c的分子量为13119。测得线虫细胞色素c的氧化还原电位为+248 mV；该值与来自哺乳动物的细胞色素c的值相当。猪蛔虫细胞色素c与牛心细胞色素c一样，对牛心细胞色素c氧化酶表现出双相动力学。比较动力学研究揭示了猪蛔虫和牛源细胞色素c与细胞色素c氧化酶之间反应的物种特异性。线粒体中的细胞色素c含量在第二幼虫阶段最高，在猪蛔虫的各个发育阶段中，该阶段的呼吸链需氧性最强。这些数据清楚地表明，所分离的成年猪蛔虫细胞色素c是第二阶段幼虫有氧呼吸链中细胞色素c氧化酶的真正底物。
