Equilibrium folding and unfolding dynamics to reveal detailed free energy landscape of src SH3 protein by magnetic tweezers  

作　　者：Huanhuan Su Hao Sun Haiyan Hong Zilong Guo Ping Yu Hu Chen 苏环环;孙皓;洪海燕;郭子龙;余平;陈虎(Institute for Biomimetics and Soft Matter,Fujian Provincial Key Laboratory for Soft Functional Materials Research,Department of Physics,Xiamen University,Xiamen 361005,China;Center of Biomedical Physics,Wenzhou Institute,University of Chinese Academy of Sciences,Wenzhou 325000,China;Oujiang Laboratory,Wenzhou 325000,China)

机构地区：[1]Institute for Biomimetics and Soft Matter,Fujian Provincial Key Laboratory for Soft Functional Materials Research,Department of Physics,Xiamen University,Xiamen 361005,China [2]Center of Biomedical Physics,Wenzhou Institute,University of Chinese Academy of Sciences,Wenzhou 325000,China [3]Oujiang Laboratory,Wenzhou 325000,China

出　　处：《Chinese Physics B》2021年第7期595-599,共5页中国物理B（英文版）

基　　金：the National Natural Science Foundation of China(Grant Nos.11874309 and 11474237);the 111 Project(Grant No.B16029)。

摘　　要：Src SH3 protein domain is a typical two-state protein which has been confirmed by research of denaturant-induced unfolding dynamics.Force spectroscopy experiments by optical tweezers and atomic force microscopy have measured the force-dependent unfolding rates with different kinds of pulling geometry.However,the equilibrium folding and unfolding dynamics at constant forces has not been reported.Here,using stable magnetic tweezers,we performed equilibrium folding and unfolding dynamic measurement and force-jump measurement of src SH3 domain with tethering points at its N-and C-termini.From the obtained force-dependent transition rates,a detailed two-state free energy landscape of src SH3 protein is constructed with quantitative information of folding free energy,transition state barrier height and position,which exemplifies the capability of magnetic tweezers to study protein folding and unfolding dynamics.

关 键 词：protein folding and unfolding magnetic tweezers free energy landscape transition state 

分 类 号：R318[医药卫生—生物医学工程]