KINETIC ROLE OF A METASTABLE NATIVE-LIKE 2-DISULFIDE SPECIES IN THE FOLDING TRANSITION OF BOVINE PANCREATIC TRYPSIN-INHIBITOR
KINETIC ROLE OF A METASTABLE NATIVE-LIKE 2-DISULFIDE SPECIES IN THE FOLDING TRANSITION OF BOVINE PANCREATIC TRYPSIN-INHIBITOR
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DOI：
10.1016/0022-2836(84)90077-9
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发表时间：
1984-01-01
影响因子：
5.6
通讯作者：
GOLDENBERG, DP
中科院分区：
文献类型：
--
作者：
CREIGHTON, TE;GOLDENBERG, DP
最近确定的牛胰蛋白酶抑制剂的形式，只有2的3个二硫键的天然蛋白质，但具有天然的构象的属性。还原抑制剂的重折叠动力学进行了重新测量，以阐明在折叠的动力学作用，这2-二硫化物物种，它是直接从一个次要的1-二硫化物中间体和重排的其他2二硫化物中间体。它不是生产性中间体，因为Cys 30和Cys 51硫醇被掩埋且不反应。通过使用分子内和分子间二硫化物试剂扩展了先前的动力学分析。获得了该途径所有分子内步骤的速率的完全一致的动力学参数，并且使用这两种类型的试剂允许详细解剖动力学途径。在这个过程中，折叠转变的能量学被更彻底地测量。关于还原牛胰蛋白酶抑制剂重折叠过程中二硫化物的形成和稳定性的独特信息提供了一个有用的描述，其中许多弱相互作用在一个蛋白质合作产生一个稳定的折叠构象。
The properties were determined of a recently identified form of bovine pancreatic trypsin inhibitor, with only 2 of the 3 disulfide bonds of the native protein, but possessing a native-like conformation. The kinetics of refolding of the reduced inhibitor were re-measured to elucidate the kinetic role in folding of this 2-disulfide species; it is formed both directly from a minor 1-disulphide intermediate and by rearrangement of the other 2 disulphide intermediates. It is not a productive intermediate because the Cys30 and Cys51 thiols are buried and unreactive. The previous kinetic analysis was extended by using both intra- and intermolecular disulphide reagents. Entirely consistent kinetic parameters for the rates of all the intramolecular steps of the pathway were obtained, and use of both types of reagents permits a detailed dissection of the kinetic pathway. In the process, the energetics of the folding transition were measured more thoroughly. The unique information available about the formation and stabilities of the disulphides during refolding of reduced bovine pancreatic trypsin inhibitor provides a useful description of the way in which numerous weak interactions within a protien co-operate to produce a stable folded conformation.