Ceruloplasmin revisited: structural and functional roles of various metal cation-binding sites.
Ceruloplasmin revisited: structural and functional roles of various metal cation-binding sites.
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DOI：
10.1107/s090744490604947x
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发表时间：
2007-02
期刊：
影响因子：
--
通讯作者：
Lindley, Peter F
中科院分区：
文献类型：
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作者：
Bento, Isabel;Peixoto, Cristina;Zaitsev, Vjacheslav N;Lindley, Peter F
使用在 100 K 温度下从冷冻至液氮温度的晶体收集的 X 射线同步加速器数据，重新研究了人血清铜蓝蛋白的三维分子结构。使用在 100 K 温度下从冷冻至液氮温度的晶体收集的 X 射线同步加速器数据，重新研究了人血清铜蓝蛋白的三维分子结构。所得模型的分辨率从 3.1 增加到 2.8 Å，全面改进了分子结构，特别是侧链。此外，它还可以明确定义以前未识别的 Ca2+ 结合和 Na+ 结合位点。 Ca2+ 阳离子位于结构域 1 中，其构型与活化的牛因子 Va 中的构型非常相似。Na+ 位点似乎在为分子顶表面的三个突起提供刚性方面发挥着结构作用。这些特征可能有助于在氧化之前将基底引导至单核铜位点，并限制接近基底的尺寸。三核铜中心似乎与室温结构不同，因为双氧部分的结合方式与枯草芽孢杆菌内生孢子外壳蛋白 CotA 中发现的方式类似。
The three-dimensional molecular structure of human serum ceruloplasmin has been reinvestigated using X-ray synchrotron data collected at 100 K from a crystal frozen to liquid-nitrogen temperature. The three-dimensional molecular structure of human serum ceruloplasmin has been reinvestigated using X-ray synchrotron data collected at 100 K from a crystal frozen to liquid-nitrogen temperature. The resulting model, with an increase in resolution from 3.1 to 2.8 Å, gives an overall improvement of the molecular structure, in particular the side chains. In addition, it enables the clear definition of previously unidentified Ca2+-binding and Na+-binding sites. The Ca2+ cation is located in domain 1 in a configuration very similar to that found in the activated bovine factor Va. The Na+ sites appear to play a structural role in providing rigidity to the three protuberances on the top surface of the molecule. These features probably help to steer substrates towards the mononuclear copper sites prior to their oxidation and to restrict the size of the approaching substrate. The trinuclear copper centre appears to differ from the room-temperature structure in that a dioxygen moiety is bound in a similar way to that found in the endospore coat protein CotA from Bacillus subtilis.