Protein folding mechanism revealed by single-molecule force spectroscopy experiments

Hao Sun; Zilong Guo; Haiyan Hong; Ping Yu; Zhenyong Xue; Hu Chen

doi:10.52601/bpr.2021.210024

Volume 7 Issue 5

Oct. 2021

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Hao Sun, Zilong Guo, Haiyan Hong, Ping Yu, Zhenyong Xue, Hu Chen. Protein folding mechanism revealed by single-molecule force spectroscopy experiments[J]. Biophysics Reports, 2021, 7(5): 399-412. doi: 10.52601/bpr.2021.210024

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Hao Sun, Zilong Guo, Haiyan Hong, Ping Yu, Zhenyong Xue, Hu Chen. Protein folding mechanism revealed by single-molecule force spectroscopy experiments[J]. Biophysics Reports, 2021, 7(5): 399-412. doi: 10.52601/bpr.2021.210024

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Protein folding mechanism revealed by single-molecule force spectroscopy experiments

doi: 10.52601/bpr.2021.210024

Hao Sun¹,
Zilong Guo^{1, 2, 3},
Haiyan Hong¹,
Ping Yu¹,
Zhenyong Xue¹,
Hu Chen^{1, 2, 3
,
,}

1.
Research Institute for Biomimetics and Soft Matter, Fujian Provincial Key Lab for Soft Functional Materials Research, Department of Physics, Xiamen University, Xiamen 361005, Fujian, China
2.
Center of Biomedical Physics, Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou 325000, Zhejiang, China
3.
Oujiang Laboratory, Wenzhou 325000, Zhejiang, China

Funds: This research was supported by the National Natural Science Foundation of China (11874309 and 11474237), 111 project (B16029), and the Start-up grant of Wenzhou Institute, University of Chinese Academy of Sciences (WIUCASQD2021008).

More Information

Corresponding author: chenhu@xmu.edu.cn (H. Chen)
Received Date: 18 July 2021
Accepted Date: 21 August 2021
Publish Date: 31 October 2021

Abstract

Abstract

Force spectroscopy experiments use mechanical force as a control factor to regulate the folding and unfolding process of proteins. Atomic force microscopy has been widely used to study the mechanical stability of proteins, and obtained unfolding forces and unfolding distance of different proteins, while recently, more low force folding and unfolding measurements were done by optical tweezers and magnetic tweezers. Due to the relatively small distortion of the free energy landscape, low force measurements give the free energy landscape information over bigger conformational space. In this review, we summarize the results of force spectroscopy experiments on different proteins. The unfolding distance obtained at high forces by atomic force microscopy are mostly smaller than 2 nm, while the unfolding distances at low forces distribute over a larger range: from a negative value to more than 6 nm. The sizes of the transition states at low force are ~4 nm for most compact two-state globular proteins, which indicates that this transition state might be the general free energy barrier separating the unfolded state and the theoretically predicated molten globule state. Up to now, only a limited number of proteins has been studied at low forces. We expect that more and more proteins with different conformations will be studied at low forces to reveal the general protein folding mechanism.
- Protein folding,
- Free energy landscape,
- Force spectroscopy,
- Molten globule state,
- Transition state

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References(98)

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