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Molecular organization and physiological functions of the respiratory chain specific for mitochondria from Plasmodium

疟原虫线粒体呼吸链的分子组织和生理功能

基本信息

批准号：
14021014
负责人：
KITA Kiyoshi
金额：
$ 36.48万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research on Priority Areas
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2005
项目状态：
已结题

项目摘要

1. Studies on the respiratory chain specific for mitochondria from PlasmodiumThe mitochondrion and the apicoplast of the malaria parasite, Plasmodium spp is microscopically observed in a close proximity to each other. In this study, we tested the suitability of two different separation techniques-Percoll density gradient centrifugation and fluorescence-activated organelle sorting for improving the purity of mitochondria isolated from the crude organelle preparation of P falciparum. To our surprise, the apicoplast was inseparable from the plasmodial mitochondrion by each method. This implies these two plasmodial organelles are bound each other. This is the first experimental evidence of a physical binding between the two organelles in Plasmodium.2. Studies on cyanide-resistant alternative oxidases from parasitic protozoa and its spescific inhibitor, ascofuranoneBased on amino acid sequence similarity and the ability to catalyze the four-electron reduction of oxygen to water using a quin … More ol substrate, mitochondrial alternative oxidase (AOX) and plastid terminal oxidase (PTOX) appear to be two closely related members of the membrane-bound diiron carboxylate group of proteins. In the current studies, we took advantage of the high activity of Trypanosoma vivax AOX (TvAOX) to examine the importance of the conserved Glu and the Tyr residues around the predicted third helix region of AOXs and PTOXs. We first compared the amino acid sequences of TvAOX with AOXs and PTOXs from various taxa and then performed alanine-scanning mutagenesis of TvAOX between amino acids Y199 and Y247. We found that the ubiquinol oxidase activity of TvAOX is completely lost in the E214A mutant, whereas mutants E215A and E216A retained more than 30% of the wild-type activity. Among the Tyr mutants, a complete loss of activity was also observed for the Y221A mutant, whereas the activities were equivalent to wild-type for the Y199A, Y212A, and Y247A mutants. Finally, residues G1u214 and Tyr221 were found to be strictly conserved among AOXs and PTOXs. Based on these findings, it appears that AOXs and PTOXs are a novel subclass of diiron carboxylate proteins that require the conserved motif E(X)eY for enzyme activity. Less

1.疟原虫线粒体特异性呼吸链的研究用显微镜观察了疟原虫的线粒体和顶质体。在这项研究中，我们测试了两种不同的分离技术-Percoll密度梯度离心和荧光激活的细胞器分选提高恶性疟原虫粗细胞器制备分离的线粒体的纯度的适用性。令我们惊讶的是，每种方法的顶质体是不可分割的原质团的孢子。这意味着这两个疟原虫细胞器相互结合。这是疟原虫中两个细胞器之间物理结合的第一个实验证据。寄生原生动物抗氰交替氧化酶及其特异性抑制剂子囊呋喃酮的研究 ...更多信息线粒体交替氧化酶（AOX）和质体末端氧化酶（PTOX）是膜结合二铁羧酸盐蛋白质组中两个密切相关的成员。在本研究中，我们利用间日锥虫AOX（TvAOX）的高活性来检查AOX和PTOX的预测的第三螺旋区域周围的保守的Glu和Tyr残基的重要性。我们首先将TvAOX的氨基酸序列与来自各种分类群的AOX和PTOX进行比较，然后在氨基酸Y199和Y247之间对TvAOX进行丙氨酸扫描诱变。我们发现TvAOX的泛醇氧化酶活性在E214 A突变体中完全丧失，而突变体E215 A和E216 A保留了野生型活性的30%以上。在Tyr突变体中，还观察到Y221 A突变体的活性完全丧失，而Y199 A、Y212 A和Y247 A突变体的活性与野生型相当。最后，发现残基G1 u214和Tyr 221在AOX和PTOX之间是严格保守的。基于这些发现，AOX和PTOX似乎是二铁羧酸盐蛋白的新亚类，其需要保守基序E（X）eY用于酶活性。少

项目成果

期刊论文数量（68）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

冨塚江利子 et al.: "Direct evidence for two distinct forms of the flavoprotein subunit of human mitochondrial complex II (succinate-ubiquinone reductase)"J.Biochem.. 134. 191-195 (2003)

Eriko Tomizuka 等人：“人线粒体复合物 II（琥珀酸泛醌还原酶）黄素蛋白亚基的两种不同形式的直接证据”J.Biochem.. 134. 191-195 (2003)

DOI：
发表时间：
期刊：
影响因子：
0
作者：
通讯作者：

Mutational analysis of the Trypanosoma vivax alternative oxidase : the E(X)eY motif is conserved in both mitochondrial alternative oxidase and plastid terminal oxidase and is indispensable for enzyme activity

间日锥虫替代氧化酶的突变分析：E(X)eY基序在线粒体替代氧化酶和质体末端氧化酶中都是保守的，并且对于酶活性是不可或缺的

DOI：
发表时间：
2005
期刊：
Biochem. Biophys. Res. Commun. 334
影响因子：
0
作者：
Nakamura;K.;Sakamoto;K.Kido;Y.;Fujimoto;Y.;Suzuki;T.;Suzuki;M.;Yabu;Y;Ohta;N.;Tsuda;A.;Onuma;M.;Kita;K.
通讯作者：
K.

Parasite mitochondria as a target of chemotherapy : The inhibitory effect of licochalcone A on the Plasmodium falciparum respiratory chain.

寄生虫线粒体作为化疗靶点：甘草查耳酮 A 对恶性疟原虫呼吸链的抑制作用。

DOI：
发表时间：
2005
期刊：
Ann.New York Acad.Sci. 1056
影响因子：
0
作者：
Sariego;I. et al.;見市文香 et al.
通讯作者：
見市文香 et al.

Mutational analysis of the Trypanosoma vivax alternative oxidase : the E(X)_6 Y motif is conserved in both mitochondrial alternative oxidase and plastid terminal oxidase and is indispensable for enzyme activity.

间日锥虫替代氧化酶的突变分析：E(X)_6 Y基序在线粒体替代氧化酶和质体末端氧化酶中都是保守的，并且对于酶活性是不可或缺的。

DOI：
发表时间：
2005
期刊：
Biochem.Biophys.Res.Commun. 334
影响因子：
0
作者：
山崎敏明;源野広和;能勢博;中村公亮 et al.
通讯作者：
中村公亮 et al.

Developmental stage-specific triacylglycerol biosynthesis, degradation and trafficking as lipid bodies in Plasmodium falciparum-infected erythrocyte.

恶性疟原虫感染的红细胞中发育阶段特异性三酰甘油生物合成、降解和作为脂质体的运输。

DOI：
发表时间：
2004
期刊：
J. Cell. Sci. 117(Pt8)
影响因子：
0
作者：
Palacpac N.M.Q.;Hiramine Y.;Mi-ichi F.;Torii M.;Kita K.;Hiramatsu R.;Horii T.;Mitamura T.
通讯作者：
Mitamura T.