The structure and the dissociation reaction of oligomers Pr(Poligo) from reduced human prion huPrP(C)(23-231) have been studied by (1)H-NMR and tryptophan fluorescence spectroscopy at varying pressure, along with circular dichroism and atomic force microscopy. The 1H-NMR and fluorescence spectral feature of the oligomer is consistent with the notion that the N-terminal residues including all seven Trp residues, are free and mobile, while residues 105 approximately 210, comprising the AGAAAAGA motif and S1-Loop-HelixA-Loop-S2-Loop-HelixC, are engaged in intra- and/ or inter-molecular interactions. By increasing pressure to 200 MPa, the oligomers tend to dissociate into monomers which may be identified with PrP(C*), a rare metastable form of PrP(C) stabilized at high pressure (Kachel et al., BMC Struct Biol 6:16). The results strongly suggest that the oligomeric form PrP(oligo) is in dynamic equilibrium with the monomeric forms via PrP(C*), namely huPrP(C)[left arrow over right arrow]huPrP(C*)[left arrow over right arrow]huPrP(oligo).

中文翻译：

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人朊病毒蛋白中的可逆单体-寡聚体转变。

已通过 (1)H-NMR 和色氨酸荧光光谱在不同压力下以及圆二色性和原子力研究了来自还原型人朊病毒 huPrP(C)(23-231) 的低聚物 Pr(Poligo) 的结构和解离反应显微镜。寡聚体的 1H-NMR 和荧光光谱特征与包括所有七个 Trp 残基在内的 N 端残基是自由和可移动的概念一致，而残基 105 大约为 210，包含 AGAAAAGA 基序和 S1-Loop-HelixA- Loop-S2-Loop-HelixC，参与分子内和/或分子间相互作用。通过将压力增加到 200 MPa，低聚物倾向于解离成单体，可以用 PrP(C*) 鉴定，PrP(C*) 是一种罕见的亚稳态形式的 PrP(C)，在高压下稳定（Kachel 等人，BMC Struct Biol 6:16 ）。