Electron transfer reactions between aromatic amine dehydrogenase and azurin.
Electron transfer reactions between aromatic amine dehydrogenase and azurin.
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芳香胺脱氢酶和天青蛋白之间的电子转移反应。
DOI：
10.1021/bi00038a020
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发表时间：
1995
期刊：
影响因子：
2.9
通讯作者：
Davidson,VL
中科院分区：
文献类型：
--
作者：
Hyun,YL;Davidson,VL
摘要：色氨酸甲萘醌（TTQ）酶、芳香胺脱氢酶（AADH）和I型铜蛋白天青蛋白之间的结合和电子转移反应已被表征。在稳态动力学测定使用天青蛋白作为电子受体，它被观察到，天青蛋白的表观Km随着离子强度的增加而降低。这些结果与TTQ酶甲胺脱氢酶（MADH）和amicyanin之间的反应所观察到的结果相反，尽管在两种情况下氧化还原蛋白对均为酸性蛋白。进一步证明天青蛋白不作为MADH的有效电子受体，并且amicyanin不作为AADH的有效电子受体。因此，虽然这两种TTQ酶各自使用I型铜蛋白作为生理电子受体，但铜蛋白作为氧化还原伴侣具有很强的特异性。用停流光谱法测定了还原型AADH与氧化型天青的电子转移反应动力学参数。根据AADH是用连二亚硫酸盐还是用底物酪胺进行化学还原，得到不同的结果。在30 ℃时的极限一级表观电子转移速率常数（& ET）分别为4和102 s-1。动力学确定的Kd值也相差2.4倍。这些数据表明，底物衍生的氨基基团的掺入到AADH的还原TTQ显着增加的表观α。AADH和天青蛋白之间的相互作用也定量使用超滤结合试验。AADH-天青蛋白复合物的Kd为300 µ。此Kd与从停流动力学研究获得的动力学确定的Kd值相关良好。讨论了amicyanin氧化还原对的异同。
Revised Manuscript Received July 17, 1995® abstract: Binding and electron transfer reactions between the tryptophan tryptophylquinone (TTQ) enzyme, aromatic amine dehydrogenase (AADH), and the type I copper protein azurin have been characterized. In steady-state kinetic assays using azurin as an electron acceptor, it was observed that the apparent Km for azurin decreased with increasing ionic strength. These results are the opposite of what was observed for the reaction between the TTQ enzyme methylamine dehydrogenase (MADH) and amicyanin, despitethe fact that in both cases the pairs of redox proteins are each acidic proteins. It was further demonstrated that azurin does not function as an effective electron acceptor for MADH, and that amicyanin does not function as an effective electron acceptor for AADH. Thus, while the two TTQ enzymes each use type I copper proteins as physiologic electronacceptors, there is a strong specificity for which copper protein serves as a redox partner. The kinetic parameters for the electron transfer reactions from reduced AADH to oxidized azurin were determined by stopped-flow spectroscopy. Different results were obtained depending upon whether AADH was reduced chemicallywith dithionite or with the substrate tyramine. The values for the limiting first-order apparent electron transfer rate constant (&ET) at 30 C were 4 and 102 s_1, respectively. Kinetically determined values of Kd also differed by a factor of 2.4. These data suggest that the incorporation of the substrate-derived amino group into the reduced TTQ of AADH significantly increases the apparent &· The interaction between AADH and azurin was also quantitated using an ultrafiltration binding assay. This yielded a Kd of 300 µ for the AADH—azurin complex. This Kd correlated well with the kinetically determined Kd values obtained from the stopped-flow kinetic studies. Similarities and differences i amicyanin redox pairs are discussed.
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影响因子：
--
作者：
E. Adman
通讯作者：
E. Adman
以 2.0 Å 和 1.8 Å 分辨率对反硝化副球菌中的阿米蓝蛋白和阿扑米蓝蛋白进行晶体结构分析
影响因子：
8
作者：
R. Durley;Longyin. Chen;F. Scott Mathews;L. W. Lim;V. Davidson
通讯作者：
V. Davidson
根据快速反应动力学数据确定酶-底物（或蛋白质-配体）相互作用的解离常数和特定速率常数。
DOI：
10.1016/s0021-9258(19)41384-7
发表时间：
1975
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
S. Strickland;G. Palmer;V. Massey
通讯作者：
V. Massey
来自粪产碱菌的天青蛋白和来自铜绿假单胞菌的细胞色素 c551 之间的电子转移。
DOI：
--
发表时间：
1981
期刊：
European Journal of Biochemistry
影响因子：
--
作者：
P. Rosen;M. Segal;I. Pecht
通讯作者：
I. Pecht
来自甲基营养细菌的甲胺脱氢酶。
影响因子：
--
作者：
Davidson,VL
通讯作者：
Davidson,VL