Preparation and Reactivity of a Tetranuclear Fe(II) Core in the Metallothionein α-Domain
Preparation and Reactivity of a Tetranuclear Fe(II) Core in the Metallothionein α-Domain
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金属硫蛋白 α 结构域四核 Fe(II) 核的制备及其反应活性
DOI：
10.1016/j.jinorgbio.2011.01.011
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Yohei Sano
中科院分区：
文献类型：
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作者：
Nonaka;Kyoshiro;Yohei Sano
金属硫蛋白（Metallothionein，MTs）是一类富含半胱氨酸的小分子蛋白质，对多种金属离子具有高亲和力，在储存必需金属和解毒中发挥重要作用。对MT氧化还原性质的研究相当有限。近年来，我们将研究重点放在MT的α结构域（MTα）作为蛋白质基质，并引入四核金属簇作为还原剂。UV-可见光谱、CD和MS数据表明，在MTα基质中形成了稳定的四核金属-半胱氨酸簇合物，其中FeII 4-MTα和CoII 4-MTα存在于水中。此外，发现FeII 4-MTα物种在温和条件下促进高铁肌红蛋白和偶氮苯衍生物的还原。在25 °C下，FeII 4-MTα（1：1）对甲基红的化学计量还原反应在6 h内的转化率为98%。这表明所有四个Fe（II）核都有助于还原。在本文中，我们描述了四核铁簇在蛋白质基质中的制备和反应性。
Metallothioneins (MTs) are small cysteine-rich proteins which exhibit high affinities for various metal ions and play roles in storage of essential metals and detoxification of toxic metals. Studies on the redox properties of MTs have been quite limited. Recently, we focused on the α-domain of MT (MTα) as a protein matrix and incorporated a tetranuclear metal cluster as a reductant. UV–visible, CD and MS data indicate the formation of the stable tetranuclear metal–cysteine cluster in the MTα matrix with FeII4–MTα and CoII4–MTα species existing in water. Furthermore, the FeII4–MTα species was found to promote the reduction of met-myoglobin and azobenzene derivatives under mild conditions. Particularly, the stoichiometric reduction of methyl red with FeII4–MTα (1:1) was found to proceed with a conversion of 98% over a period of 6 h at 25 °C. This indicates that all of the four Fe(II) cores contribute to the reduction. In this paper, we describe the preparation and reactivity of the tetranuclear iron cluster in the protein matrix.