Structure-function relationships in mitochondrial complex I of the strictly aerobic yeast Yarrowia lipolytica
Structure-function relationships in mitochondrial complex I of the strictly aerobic yeast Yarrowia lipolytica
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DOI：
10.1042/bst0330840
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发表时间：
2005-08-01
影响因子：
3.9
通讯作者：
Kerscher, S
中科院分区：
文献类型：
--
作者：
Brandt, U;Abdrakhmanova, A;Kerscher, S
专性需氧酵母解脂耶氏酵母已被建立为分析线粒体复合物 I 的强大模型系统。利用基因组学和蛋白质组学方法的组合，总共鉴定了 37 个亚基。一些辅助亚基预计是 STMD（单跨膜结构域）蛋白。解脂耶氏酵母复合体 I 的定点诱变提供了强有力的证据，表明泛醌还原催化核心的重要部分位于 49 kDa 和 PSST 亚基中，并且可以使用远缘相关酶（即来自 Desulfovibrio spp 的水溶性 [NiFe] 氢化酶）的 X 射线结构进行建模。铁硫簇 N2 与氢化酶近端簇相关，直接参与醌还原。 49 kDa 亚基的 His(226) 和 Arg(141) 诱变提供了对簇 N2 周围结构-功能关系的详细了解。总的来说，我们的研究结果表明，复合物 I 的质子泵采用长程构象相互作用，而泛醌中间体在该机制中发挥着关键作用。
The obligate aerobic yeast Yarrowia lipolytica has been established as a powerful model system for the analysis of mitochondrial complex I. Using a combination of genomic and proteomic approaches, a total of 37 subunits was identified. Several of the accessory subunits are predicted to be STMD (single transmembrane domain) proteins. Site-directed mutagenesis of Y. lipolytica complex I has provided strong evidence that a significant part of the ubiquinone reducing catalytic core resides in the 49 kDa and PSST subunits and can be modelled using X-ray structures of distantly related enzymes, i.e. water-soluble [NiFe] hydrogenases from Desulfovibrio spp. iron-sulphur cluster N2, which is related to the hydrogenase proximal cluster, is directly involved in quinone reduction. Mutagenesis of His(226) and Arg(141) of the 49 kDa subunit provided detailed insight into the structure-function relationships around cluster N2. Overall, our findings suggest that proton pumping by complex I employs long-range conformational interactions and ubiquinone intermediates play a critical role in this mechanism.