Crystal structure of quinol-dependent nitric oxide reductase from Geobacillus stearothermophilus
Crystal structure of quinol-dependent nitric oxide reductase from Geobacillus stearothermophilus
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DOI：
10.1038/nsmb.2213
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发表时间：
2012-02-01
影响因子：
16.8
通讯作者：
Shiro, Yoshitsugu
中科院分区：
文献类型：
--
作者：
Matsumoto, Yushi;Tosha, Takehiko;Shiro, Yoshitsugu
嗜热硬脂菌（G. stearothermophilus）中喹啉依赖性一氧化氮还原酶（qNOR）的结构在2.5埃分辨率下被表征，该酶催化NO的还原产生主要的臭氧消耗气体N2O。的整体折叠qNOR类似于细胞色素c的依赖也(cNOR),和一些结构特点cNOR特点,如钙离子结合位点和亲水性细胞色素c域,在qNOR观察,即使它没有血红素c。cNOR相比,基于结构的诱变和qNOR的分子动力学模拟研究表明,水通道从细胞质中可以作为一个质子转移催化反应途径。qNOR与cNOR以及有氧和微有氧呼吸氧化酶的进一步结构比较阐明了它们的进化关系和可能的功能转换。
The structure of quinol-dependent nitric oxide reductase (qNOR) from G. stearothermophilus, which catalyzes the reduction of NO to produce the major ozone-depleting gas N2O, has been characterized at 2.5 angstrom resolution. The overall fold of qNOR is similar to that of cytochrome c dependent NOR (cNOR), and some structural features that are characteristic of cNOR, such as the calcium binding site and hydrophilic cytochrome c domain, are observed in qNOR, even though it harbors no heme c. In contrast to cNOR, structure-based mutagenesis and molecular dynamics simulation studies of qNOR suggest that a water channel from the cytoplasm can serve as a proton transfer pathway for the catalytic reaction. Further structural comparison of qNOR with cNOR and aerobic and microaerobic respiratory oxidases elucidates their evolutionary relationship and possible functional conversions.