Chaperonins are known to facilitate the productive folding of numerous misfolded proteins. Despite their established importance, the mechanism of chaperonin-assisted protein folding remains unknown. In the present art...Chaperonins are known to facilitate the productive folding of numerous misfolded proteins. Despite their established importance, the mechanism of chaperonin-assisted protein folding remains unknown. In the present article, all-atom explicit solvent molecular dynamics （MD） simulations have been performed for the first time on rhodanese folding in a series of cavity-size and cavity-charge chaperonin mutants. A compromise between stability and flexibility of chaperonin structure during the substrate folding has been observed and the key factors affecting this dynamic process are discussed.展开更多
Fluorescence lifetime and anisotropy has become a prevalent tool to detect the structure change and motility property of proteins. YgaP is the only membrane-integrated rhodanese in E. coli. The sulfur transfer process...Fluorescence lifetime and anisotropy has become a prevalent tool to detect the structure change and motility property of proteins. YgaP is the only membrane-integrated rhodanese in E. coli. The sulfur transfer process has been characterized by various studies. However, the mechanism of the outward transportation of SCN-remains unclear. In this work, we examined the fluorescence lifetime and anisotropy of site-specific incorporated unnatural amino acid 7-HC to study the conformational change of YgaP upon SCN-binding. We also compared the fluorescence changes between detergent-wrapped environment in DPC and intact native membrane environment in SMA. Our results suggested the presence of at least two different conformations in YgaP protein. Both the residues in the middle of TMH2 and the residues near extracellular side play important roles in the binding and/or output of SCN-. SMA is a good material to reflect the in situ conformation changes of protein than micelles.展开更多
基金supported by the Knowledge Innovation Programof Chinese Academy of Sciences under the Grant Nos. O82811 and KGCX2-YW-124National Natural Science Foundation of Chinaunder the Grant Nos. 20490201 and 20221603
文摘Chaperonins are known to facilitate the productive folding of numerous misfolded proteins. Despite their established importance, the mechanism of chaperonin-assisted protein folding remains unknown. In the present article, all-atom explicit solvent molecular dynamics （MD） simulations have been performed for the first time on rhodanese folding in a series of cavity-size and cavity-charge chaperonin mutants. A compromise between stability and flexibility of chaperonin structure during the substrate folding has been observed and the key factors affecting this dynamic process are discussed.
基金supported by the National Key R&D Program of China (Nos. 2016YFA0400900, 2017YFA0505300)the Instrument Developing Project of the Chinese Academy of Sciences (No. YZ201564)
文摘Fluorescence lifetime and anisotropy has become a prevalent tool to detect the structure change and motility property of proteins. YgaP is the only membrane-integrated rhodanese in E. coli. The sulfur transfer process has been characterized by various studies. However, the mechanism of the outward transportation of SCN-remains unclear. In this work, we examined the fluorescence lifetime and anisotropy of site-specific incorporated unnatural amino acid 7-HC to study the conformational change of YgaP upon SCN-binding. We also compared the fluorescence changes between detergent-wrapped environment in DPC and intact native membrane environment in SMA. Our results suggested the presence of at least two different conformations in YgaP protein. Both the residues in the middle of TMH2 and the residues near extracellular side play important roles in the binding and/or output of SCN-. SMA is a good material to reflect the in situ conformation changes of protein than micelles.
