Activity of one of two engineered heterodimers of AhpF, the NADH:peroxiredoxin oxidoreductase from Salmonella typhimurium, reveals intrasubunit electron transfer between domains.
Activity of one of two engineered heterodimers of AhpF, the NADH:peroxiredoxin oxidoreductase from Salmonella typhimurium, reveals intrasubunit electron transfer between domains.
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AhpF 的两个工程异二聚体之一（来自鼠伤寒沙门氏菌的 NADH：过氧化还原酶氧化还原酶）的活性揭示了结构域之间的亚基内电子转移。
DOI：
10.1021/bi002766h
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发表时间：
2001
期刊：
影响因子：
2.9
通讯作者：
Poole,LB
中科院分区：
文献类型：
--
作者：
Reynolds,CM;Poole,LB
AhpF是鼠伤寒沙门氏菌非烷基氢过氧化物还原酶系统的黄蛋白还原酶组分，它催化该系统的另一组分AhpC的过氧化物活性位点的亚基间二硫键的还原，AhpC是过氧化物还原素家族的成员。先前的研究表明，AhpF可以被分解成两个功能单元，一个类似硫氧还蛋白还原酶的c端（含有FAD和一个氧化还原活性二硫化物，Cys345 - Cys348）和一个含有第二个氧化还原活性二硫化物中心的n端结构域（Cys129 - Cys132）。n端结构域作为AhpC的直接还原剂，介导AhpF c端氧化还原中心的电子转移，已经通过几种方法得到了证实。然而，尚不清楚在二聚AhpF中，电子在c端和n端二硫化中心之间的转移是作为亚基间还是亚基内的过程发生的。因此，两个异二聚AhpF物种被创造出来，其中两条通路中的一条被完全破坏，而另一条在每个结构中部分完整。只有含有一个野生型AhpF单体和一个突变（和截断）AhpF单体的异源二聚体与AhpC表现出过氧化物酶活性，这表明AhpF结构域之间的电子转移是一个亚基内过程。
AhpF, the flavoprotein reductase component of theSalmonella typhimuriumalkyl hydroperoxide reductase system, catalyzes the reduction of an intersubunit disulfide bond in the peroxidatic active site of the system's other component, AhpC, a member of the peroxiredoxin family. Previous studies have shown that AhpF can be dissected into two functional units, a thioredoxin reductase-like C-terminus (containing FAD and a redox-active disulfide, Cys345−Cys348) and an N-terminal domain containing a second redox-active disulfide center (Cys129−Cys132). The role of the N-terminal domain as the direct reductant of AhpC, mediating electron transfer from the C-terminal redox centers of AhpF, has been firmly established by several approaches. Not known, however, was whether the transfer of electrons between the C-terminal and N-terminal disulfide centers occurred as an inter- or intrasubunit process in dimeric AhpF. Two heterodimeric AhpF species were therefore created in which one of the two pathways was completely disrupted while the other was left partially intact in each construct. Only the heterodimer containing one monomer of wild type AhpF and a monomer of mutated (and truncated) AhpF exhibited peroxidase activity with AhpC indicating that electron transfer between domains of AhpF is an intrasubunit process.