The role of molecular crowding in long-range metalloprotein electron transfer: Dissection into site- and scaffold-specific contributions
Here we report the effect of molecular crowding on long-range protein electron transfer (ET) and disentangle the specific responses of the redox site and the protein milieu. To this end, we studied two different one-electron redox proteins that share the cupredoxin fold but differ in the metal cente...
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2019
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| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00134686_v294_n_p117_Zitare http://hdl.handle.net/20.500.12110/paper_00134686_v294_n_p117_Zitare |
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paper:paper_00134686_v294_n_p117_Zitare2023-06-08T14:35:50Z The role of molecular crowding in long-range metalloprotein electron transfer: Dissection into site- and scaffold-specific contributions Electron transfer Frictional control Loop engineering Metalloproteins Molecular crowding Activation energy Electron transitions Friction Intelligent agents Metals Scaffolds Scaffolds (biology) Dynamical coupling Electron transfer Electronic coupling Metallo-proteins Metalloprotein Molecular crowding Orthologous proteins Redox proteins Proteins Here we report the effect of molecular crowding on long-range protein electron transfer (ET) and disentangle the specific responses of the redox site and the protein milieu. To this end, we studied two different one-electron redox proteins that share the cupredoxin fold but differ in the metal center, T1 mononuclear blue copper and binuclear CuA, and generated chimeras with hybrid properties by incorporating different T1 centers within the CuA scaffold or by swapping loops between orthologous proteins from different organisms to perturb the CuA site. The heterogeneous ET kinetics of the different proteins was studied by protein film electrochemistry at variable electronic couplings and in the presence of two different crowding agents. The results reveal a strong frictional control of the ET reactions, which for 10 Å tunnelling distances results in a 90% drop of the ET rate when viscosity is matched to that of the mitochondrial interior (ca. 55 cP) by addition of either crowding agent. The effect is ascribed to the dynamical coupling of the metal site and the milieu, which for T1 is found to be twice stronger than for CuA, and the activation energy of protein-solvent motion that is dictated by the overall scaffold. This work highlights the need of explicitly considering molecular crowding effects in protein ET. © 2018 Elsevier Ltd 2019 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00134686_v294_n_p117_Zitare http://hdl.handle.net/20.500.12110/paper_00134686_v294_n_p117_Zitare |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Electron transfer Frictional control Loop engineering Metalloproteins Molecular crowding Activation energy Electron transitions Friction Intelligent agents Metals Scaffolds Scaffolds (biology) Dynamical coupling Electron transfer Electronic coupling Metallo-proteins Metalloprotein Molecular crowding Orthologous proteins Redox proteins Proteins |
| spellingShingle |
Electron transfer Frictional control Loop engineering Metalloproteins Molecular crowding Activation energy Electron transitions Friction Intelligent agents Metals Scaffolds Scaffolds (biology) Dynamical coupling Electron transfer Electronic coupling Metallo-proteins Metalloprotein Molecular crowding Orthologous proteins Redox proteins Proteins The role of molecular crowding in long-range metalloprotein electron transfer: Dissection into site- and scaffold-specific contributions |
| topic_facet |
Electron transfer Frictional control Loop engineering Metalloproteins Molecular crowding Activation energy Electron transitions Friction Intelligent agents Metals Scaffolds Scaffolds (biology) Dynamical coupling Electron transfer Electronic coupling Metallo-proteins Metalloprotein Molecular crowding Orthologous proteins Redox proteins Proteins |
| description |
Here we report the effect of molecular crowding on long-range protein electron transfer (ET) and disentangle the specific responses of the redox site and the protein milieu. To this end, we studied two different one-electron redox proteins that share the cupredoxin fold but differ in the metal center, T1 mononuclear blue copper and binuclear CuA, and generated chimeras with hybrid properties by incorporating different T1 centers within the CuA scaffold or by swapping loops between orthologous proteins from different organisms to perturb the CuA site. The heterogeneous ET kinetics of the different proteins was studied by protein film electrochemistry at variable electronic couplings and in the presence of two different crowding agents. The results reveal a strong frictional control of the ET reactions, which for 10 Å tunnelling distances results in a 90% drop of the ET rate when viscosity is matched to that of the mitochondrial interior (ca. 55 cP) by addition of either crowding agent. The effect is ascribed to the dynamical coupling of the metal site and the milieu, which for T1 is found to be twice stronger than for CuA, and the activation energy of protein-solvent motion that is dictated by the overall scaffold. This work highlights the need of explicitly considering molecular crowding effects in protein ET. © 2018 Elsevier Ltd |
| title |
The role of molecular crowding in long-range metalloprotein electron transfer: Dissection into site- and scaffold-specific contributions |
| title_short |
The role of molecular crowding in long-range metalloprotein electron transfer: Dissection into site- and scaffold-specific contributions |
| title_full |
The role of molecular crowding in long-range metalloprotein electron transfer: Dissection into site- and scaffold-specific contributions |
| title_fullStr |
The role of molecular crowding in long-range metalloprotein electron transfer: Dissection into site- and scaffold-specific contributions |
| title_full_unstemmed |
The role of molecular crowding in long-range metalloprotein electron transfer: Dissection into site- and scaffold-specific contributions |
| title_sort |
role of molecular crowding in long-range metalloprotein electron transfer: dissection into site- and scaffold-specific contributions |
| publishDate |
2019 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00134686_v294_n_p117_Zitare http://hdl.handle.net/20.500.12110/paper_00134686_v294_n_p117_Zitare |
| _version_ |
1768542486863544320 |