Hidden Intermediate State and Second Pathway Determining Folding and Unfolding Dynamics of GB1 Protein at Low Forces
- 物理技术－已发表论文 
【Abstract】Atomic force microscopy experiments found that GB1, a typical two-state model protein used for study of folding and unfolding dynamics, can sustain forces of more than 100 pN, but its response to low forces still remains unclear. Using ultrastable magnetic tweezers, we discovered that GB1 has an unexpected nonmonotonic force-dependent unfolding rate at 5–160 pN, from which a free energy landscape with two main barriers and a hidden intermediate state was constructed. A model combining two separate models by Dudko et al. with two pathways between the native state and this intermediate state is proposed to rebuild the unfolding dynamics over the full experimental force range. One candidate of this transient intermediate state is the theoretically proposed molten globule state with a loosely collapsed conformation, which might exist universally in the folding and unfolding processes of two-state proteins.
Description厦门大学物理学系陈虎教授与吴晨旭教授，在蛋白质折叠与去折叠动力学方面取得新的研究进展，发现典型的两态模型蛋白质GB1在折叠去折叠过程中会经过一个不稳定的隐藏中间态，并且在自然状态与这个中间态之间存在两条不同的转变路径。 厦门大学物理系博士生郭子龙是文章第一作者，陈虎和吴晨旭老师为通讯作者，南京大学曹毅教授和王炜教授在样品制备方面和实验设计方面做出重要贡献。This research was supported by the National Nature Science Foundation of China (No. 11874309, No. 11474237, and No. 11574310 to H. C.) and the 111 Project (B16029).
CitationPhysical Review Letters,,2020,125(19):198101