Characterization of hydride transfer to flavin adenine dinucleotide in neuronal nitric oxide synthase reductase domain: geometric relationship between the nicotinamide and isoalloxazine rings.
Characterization of hydride transfer to flavin adenine dinucleotide in neuronal nitric oxide synthase reductase domain: geometric relationship between the nicotinamide and isoalloxazine rings.
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神经元一氧化氮合酶还原酶结构域中氢化物转移至黄素腺嘌呤二核苷酸的表征：烟酰胺和异咯嗪环之间的几何关系。
DOI：
10.1006/abbi.2001.2588
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
Hinck,AP
中科院分区：
文献类型：
--
作者：
Miller,RT;Hinck,AP
基于神经元型一氧化氮合酶（nNOSred）还原酶结构域与NADPH-细胞色素P450还原酶（CPR）结构域在结构和功能上的相似性，我们确定了这两种蛋白质从NADPH到黄素腺嘌呤二核苷酸（FAD）的氢化物转移特征是否相似。其次，我们质疑氢化物从NADPH转移到nNOSred或holo-nNOS是否是这两种蛋白质催化的反应的速率限制。利用500 MHz质子NMR和氘代底物，我们确定了从NADPH的氢化物转移的立体特异性和糖苷键周围的烟酰胺环的构象在CPR和nNOSred之间是相似的。具体来说，nNOSred从NADPH中提取A侧氢，并且烟酰胺环处于反构象。我们确定，氢化物转移到FAD的速率似乎成为部分速率限制，只有特别好的电子受体，如细胞色素c。在本研究所用的任何条件下，氢化物转移都不是NO·生成的速率限制。有趣的是，当在高离子强度缓冲液中进行测定时，在使用nNOS和nNOSred的细胞色素c还原酶测定中氘同位素效应降低，表明氢化物转移至FAD的速率增加。这些结果与CPR获得的结果形成鲜明对比（D。S. Sem和C. B。Kasper，1995，Biochemistry 34，3391-3398），其中氢化物转移在高离子强度下是部分速率限制的，但在低离子强度下不是。在高和低离子强度的条件下，用CPR和nNOSred观察到的氘同位素效应中看似相反的结果表明这些重要黄素蛋白的结构和/或调节的差异。
Based on the similarity in both structure and function of the reductase domain of neuronal nitric oxide synthase (nNOSred) to that of NADPH-cytochrome P450 reductase (CPR), we determined whether the characteristics of hydride transfer from NADPH to flavin adenine dinucleotide (FAD) were similar for both proteins. Secondly, we questioned whether hydride transfer from NADPH to either nNOSred or holo-nNOS was rate limiting for reactions catalyzed by these two proteins. Utilizing 500 MHz proton NMR and deuterated substrate, we determined that the stereospecificity of hydride transfer from NADPH and the conformation of the nicotinamide ring around the glycosidic bond were similar between CPR and nNOSred. Specifically, nNOSred abstracts the A-side hydrogen from NADPH, and the nicotinamide ring is in the anti conformation. We determined that the rate of hydride transfer to FAD appears to become partially rate limiting only for exceptionally good electron acceptors such as cytochrome c. Hydride transfer is not rate limiting for NO· production under any conditions used in this study. Interestingly, the deuterium isotope effect was decreased in the cytochrome c reductase assay with both nNOS and nNOSred when the assays were conducted in high ionic strength buffer, suggesting an increase in the rate of hydride transfer to FAD. These results are in stark contrast to results obtained with CPR (D. S. Sem and C. B. Kasper, 1995, Biochemistry 34, 3391–3398) whereby hydride transfer is partially rate limiting at high, but not at low, ionic strength. The seemingly opposite results in deuterium isotope effect observed with CPR and nNOSred, under conditions of high and low ionic strength, suggest differences in structure and/or regulation of these important flavoproteins.
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NADPH-细胞色素 P-450 氧化还原酶中烟酰胺和异咯嗪环之间的几何关系：对进化和功能相关黄素蛋白分类的影响。
影响因子：
2.9
作者：
Sem,DS;Kasper,CB
通讯作者：
Kasper,CB
钙调蛋白通过双重机制控制神经元一氧化氮合酶。
DOI：
--
发表时间：
1994
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Abu-Soud,HM;Yoho,LL;Stuehr,DJ
通讯作者：
Stuehr,DJ
盐对一氧化氮合酶活性的异构体特异性影响。
DOI：
10.1016/s0167-4838(98)00138-1
发表时间：
1998
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
Schrammel,A;Gorren,AC;Stuehr,DJ;Schmidt,K;Mayer,B
通讯作者：
Mayer,B
大鼠神经元一氧化氮合酶的血红素和黄素结合域作为不同多肽的原核表达：将血红素结合近端硫醇配体鉴定为半胱氨酸-415。
影响因子：
2.9
作者：
McMillan,K;Masters,BS
通讯作者：
Masters,BS
影响因子：
2.9
作者：
VIOLA, RE;COOK, PF;CLELAND, WW
通讯作者：
CLELAND, WW