High-pressure NMR study of the dissociation of Arc repressor.
High-pressure NMR study of the dissociation of Arc repressor.
复制标题
电弧抑制子离解的高压核磁共振研究。
DOI：
10.1021/bi00193a020
复制
发表时间：
1994
期刊：
影响因子：
2.9
通讯作者：
Silva,JL
中科院分区：
文献类型：
--
作者：
Peng,X;Jonas,J;Silva,JL
1994年5月5日收到的修订版Mandalpt ®摘要：Arc阻遏物的不同变性状态通过一维和二维NMR以及荧光光谱进行表征。压力的增加促进了Arc阻遏物结构的连续变化：从中性二聚体到预解离状态，再到变性的熔融球单体。一个紧凑的状态（熔融球）的Arc阻遏物的Arc阻遏物的压力，而高温和尿素诱导解离和展开较少的结构构象的解离中获得。在压力下（高达5.0 kbar）的单体的NMR光谱是典型的熔融球，它们是相当大的不同，从那些天然的二聚体和热或化学变性的单体。在高压下的NMR谱中，许多共振的谱线展宽和重叠表明，在中间交换速率下，熔融球的许多不同构象之间存在相互转化。二维NOE谱表明，压力变性后的单体保留了大量的二级结构。解离状态下3-折叠区域中NOE的存在表明天然二聚体中的亚基间3-折叠（残基6-14）被单体内3-折叠取代。解离前2D NMR谱的变化表明存在一个预解离状态，可能代表Arc阻遏蛋白折叠和亚基缔合途径的中间体。
Revised Manuscript Received May 5, 1994® abstract: Different denatured states of Arc repressor were characterized by one-dimensional and twodimensional NMR and by fluorescence spectroscopy. Increasing pressure promoted sequential changes in the structure of Arc repressor: from thenative dimer through a predissociated state to a denaturated molten globule monomer. A compact state (molten globule) of Arc repressor was obtained in the dissociation of Arc repressor by pressure whereas high temperature and urea induced dissociation and unfolding to less structured conformations. The NMR spectra of the monomer under pressure (up to 5.0 kbar) are typical of a molten globule, and they are considerably different from those of the native dimer and the thermally or chemically denatured monomer. The substantial line broadening and overlap of many resonances in theNMR spectra at high pressures indicatethat there is interconversion between a number of different conformations of the molten globule at an intermediate exchange rate. The two-dimensional NOE spectra show that thepressure-denatured monomer retains substantial secondary structure. The presence of NOEs in the 3-sheet region in the dissociated state suggests that the intersubunit 3-sheet (residues 6-14) in the native-dimer is replaced by an intramonomer 3-sheet. Changes in 2D NMR spectra prior to dissociation indicate theexistence of a predissociated state that may represent an intermediate in the folding and subunit association pathway of Arc repressor.