摘要
实验证明细胞色素c具有很强的抗氧化功能 ,在线粒体中氧化态的细胞色素c直接清除O2 ·,还原态的细胞色素c清除H2 O2 .由于呼吸链传递电子合成ATP的同时 ,总有少部分电子从呼吸链底物端的复合物Ⅰ和Ⅲ漏出 ,而且漏出的电子首先使氧分子还原成O2 ·,然后O2 ·歧化成H2 O2 ,所以细胞色素c清除O2 ·和H2 O2 的功能使呼吸链出现了两条电子漏旁路 .细胞色素c通过这两条电子漏路径实现其控制线粒体中O2 ·和H2 O2 水平的功能 .根据两条电子漏旁路都是O2 ·代谢路径的事实 ,引进了线粒体自由基代谢的概念 。
Cytochrome c has been proved to be a powerful scavenger of O-2(radical anion) and H2O2, the ferricytochrome c scavenges O-2(radical anion) and the ferrocytochrome c scavenges H2O2. As the respiratory chain leak some electrons from complex I and III to generate O-2(radical anion) and then O-2(radical anion) dismutate to H2O2, the scavenge of O-2(radical anion) and H2O2 by cytochrome c makes respiratory chain operated with two electron leak bypass. Cytochrome c plays a role to keep O-2(radical anion) and H2O2 in the normal physiological level in mitochondria. A concept of radical metabolism is introduced into mitochondria based on the electron leak bypass is the metabolic path of O-2(radical anion). The role of electron leak of respiratory chain in cell apoptosis is discussed in the dysfunction of radical metabolism of mitochondria.
出处
《生物化学与生物物理进展》
SCIE
CAS
CSCD
北大核心
2003年第4期655-657,共3页
Progress In Biochemistry and Biophysics
基金
国家自然科学基金资助项目 (3 95 70 193 )
国家科学技术部资金部分资助~~
关键词
呼吸链电子漏
细胞凋亡
抗氧化
细胞色素C
线粒体自由基代谢
cytochrome c
radical scavenger
electron leak of respiratory chain
radical metabolism of mitochondria
