Proton transfer via a transient linear water-molecule chain in a membrane protein
| العنوان: | Proton transfer via a transient linear water-molecule chain in a membrane protein |
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| المؤلفون: | Erik Freier, Steffen Wolf, Klaus Gerwert |
| المصدر: | Proceedings of the National Academy of Sciences. 108:11435-11439 |
| بيانات النشر: | Proceedings of the National Academy of Sciences, 2011. |
| سنة النشر: | 2011 |
| مصطلحات موضوعية: | Halobacterium salinarum, Models, Molecular, Conformational change, Protein Conformation, Protonation, Molecular Dynamics Simulation, Biophysical Phenomena, Molecular dynamics, Protein structure, Spectroscopy, Fourier Transform Infrared, Water cluster, Binding Sites, Multidisciplinary, biology, Chemistry, Membrane Proteins, Water, Hydrogen Bonding, Bacteriorhodopsin, Biological Sciences, Proton pump, Crystallography, Membrane, Amino Acid Substitution, Bacteriorhodopsins, Mutagenesis, Site-Directed, biology.protein, Protons, Hydrophobic and Hydrophilic Interactions, Protein Binding |
| الوصف: | High-resolution protein ground-state structures of proton pumps and channels have revealed internal protein-bound water molecules. Their possible active involvement in protein function has recently come into focus. An illustration of the formation of a protonated protein-bound water cluster that is actively involved in proton transfer was described for the membrane protein bacteriorhodopsin (bR) [Garczarek F, Gerwert K (2006) Nature 439:109–112]. Here we show through a combination of time-resolved FTIR spectroscopy and molecular dynamics simulations that three protein-bound water molecules are rearranged by a protein conformational change that resulted in a transient Grotthuss-type proton-transfer chain extending through a hydrophobic protein region of bR. This transient linear water chain facilitates proton transfer at an intermediate conformation only, thereby directing proton transfer within the protein. The rearrangement of protein-bound water molecules that we describe, from inactive positions in the ground state to an active chain in an intermediate state, appears to be energetically favored relative to transient incorporation of water molecules from the bulk. Our discovery provides insight into proton-transfer mechanisms through hydrophobic core regions of ubiquitous membrane spanning proteins such as G-protein coupled receptors or cytochrome C oxidases. |
| تدمد: | 1091-6490 0027-8424 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::dfbde4fc7d4da47f50011cc8ab3c9540Test https://doi.org/10.1073/pnas.1104735108Test |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....dfbde4fc7d4da47f50011cc8ab3c9540 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 10916490 00278424 |
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