Biochemical studies on aerobic-anaerobic respiratory transition in mitochondria from parasitic helminthes

寄生蠕虫线粒体有氧-无氧呼吸转变的生化研究

基本信息

批准号：
03670201
负责人：
TAKAMIYA Shinzaburo
金额：
$ 1.09万
依托单位：
Juntendo University School of Medicine
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1991
资助国家：
日本
起止时间：
1991 至 1992
项目状态：
已结题

项目摘要

1. The primary structures of the Ip subunit of complex II of adult Ascaris were determined using peptides separated on Biogel P-60 in the presence of sodium dodecylsulfate. The alanine-threonine cluster, a conserved region in the amino terminus of the mammalian Ip subunit, was found in the Ascaris Ip subunit. Two of the three cystein-rich segments generally conserved in the Ip subunit were sequenced following chemical modification of cystein residues. From a comparative analysis of the sequences, the Ip subunit of complex II in Ascaris adult appears to be more closely related to those of bacterial SDH and mammalian complex II than to that of bacterial FRD, even though Ascaris complex II shows a high FRD activity.2. To elucidate mechanisms of aerobic-anaerobic respiratory transition during development of Ascaris nematode, the larval respiratory chain and its complex II have been characterized in the isolated mitochondria by spectrophotometry, immunoblotting using anti adult complex II antibodies and determination of quinones. The results obtained showed that L2 larvae were the most aerobic among stages studied and the larval complex II was different from the adult counterpart. Furthermore, evidence showing biosynthetic conversion of quinones durig development was obtained.3. Mitochondria from a lung fluke, Paragonimus westermani, were isolated to study the worm respiratory chain. Interestingly, the adult worm mitochondria were shown to possess both aerobic and anaerobic respiratory chains, i. e., cyanide-sensitive succinate oxidase and NADH-fumarate reductase system, respectively. The mitochondria were also found to contain both rhodoquinone-10 and ubiquinone-10.

1. 在十二烷基硫酸钠存在下，使用 Biogel P-60 上分离的肽确定了成虫复合物 II 的 Ip 亚基的一级结构。丙氨酸-苏氨酸簇是哺乳动物 Ip 亚基氨基末端的保守区域，在蛔虫 Ip 亚基中被发现。在对半胱氨酸残基进行化学修饰后，对 Ip 亚基中通常保守的三个富含半胱氨酸的片段中的两个进行了测序。从序列比较分析来看，成虫蛔虫复合物II的Ip亚基与细菌SDH和哺乳动物复合物II的Ip亚基的相关性似乎比与细菌FRD的相关性更密切，尽管蛔虫复合物II显示出高FRD活性。 2.为了阐明蛔虫线虫发育过程中需氧-厌氧呼吸转变的机制，通过分光光度法、使用抗成虫复合物 II 抗体的免疫印迹和醌的测定，对分离的线粒体中的幼虫呼吸链及其复合物 II 进行了表征。获得的结果表明，L2 幼虫是所研究阶段中最有氧的，并且幼虫复合体 II 与成虫对应物不同。此外，还获得了醌在发育过程中生物合成转化的证据。 3．从肺吸虫（卫氏并殖吸虫）中分离线粒体，用于研究蠕虫呼吸链。有趣的是，成虫线粒体被证明具有需氧和厌氧呼吸链，即。即，分别是氰化物敏感的琥珀酸氧化酶和NADH-富马酸还原酶系统。线粒体还被发现含有 rhodoquinone-10 和 ubiquinone-10。