Structural and dynamic characterization of copper(11) binding of the human prion protein outside the octarepeat region
Structural and dynamic characterization of copper(11) binding of the human prion protein outside the octarepeat region
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DOI：
10.1002/chem.200601225
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发表时间：
2007-01-01
影响因子：
4.3
通讯作者：
Valensin, Gianni
中科院分区：
文献类型：
--
作者：
Berti, Francesco;Gaggelli, Elena;Valensin, Gianni
人PrP92-100(SP1)、hPrP106-113(SP2)、hPrP91-120(M)和hPrP91-114(LP2)片段被用来描述铜-II结合位点(S)。将从LP1或LP2获得的核磁共振和EPR谱结果与从SP1和SP2获得的结果进行了比较。在低金属与高金属肽比例下，ESI质谱学证实并证实了His96和His111两个结合位点的共存。虽然室温核磁共振谱数据与以His111为中心的结合部位大约是以His96为中心的结合部位的四倍一致，但低温EPR光谱结果却证明了相反的趋势。这种分歧也出现在文献中，通过依赖温度的分子动力学运行证明Met112在室温下接近金属，这一过程有望通过疏水屏蔽金属配位球来稳定His111中心的结合部位。
Human prion protein (hPrP) fragments encompassing the 91-120 region, namely hPrP92-100 (SP1), hPrP106-113 (SP2), hPrP91-120 (M), and hPrP91-114 (LP2), were considered for delineation of the Cu-II-binding site(s). NMR and EPR spectroscopy results obtained from LP1 or LP2 were compared with those obtained from SP1 and SP2. The coexistence of two binding sites, one centered at His96 and the other at His111, was evidenced and ratified by ESI mass spectrometry at low and high metal:peptide ratios. While room-temperature NMR spectroscopy data were consistent with the binding site centered on His111 being approximately fourfold stronger than that centered on His96, low-temperature EPR spectroscopy results yielded evidence for the opposite trend. This disagreement, which has also occurred in the literature, was clarified by temperature-dependent molecular dynamics runs that demonstrated Met112 approaching the metal at room temperature, a process that is expected to stabilize the His111-centered binding site through hydrophobic shielding of the metal coordination sphere.