Solid-state NMR analysis of the sodium pump Krokinobacter rhodopsin 2 and its H30A mutant
| Autor: | Christian Bamann, Johanna Becker-Baldus, Josef Wachtveitl, Peter Eberhardt, Clara Nassrin Kriebel, Lynda J. Brown, Richard C. D. Brown, Clemens Glaubitz, Alexander J. Leeder, Jagdeep Kaur, Orawan Jakdetchai, Ingrid Weber |
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| Rok vydání: | 2019 |
| Předmět: |
Models
Molecular Magnetic Resonance Spectroscopy Protein Conformation Sodium Retinal binding chemistry.chemical_element Protomer 03 medical and health sciences chemistry.chemical_compound Bacterial Proteins Structural Biology Rhodopsins Microbial Amino Acid Sequence Binding site 030304 developmental biology 0303 health sciences Molecular Structure biology Chemistry 030302 biochemistry & molecular biology Polyene Crystallography Ion pump Solid-state nuclear magnetic resonance Rhodopsin Mutation biology.protein Sodium-Potassium-Exchanging ATPase Flavobacteriaceae |
| Zdroj: | Journal of Structural Biology. 206:55-65 |
| ISSN: | 1047-8477 |
| DOI: | 10.1016/j.jsb.2018.06.001 |
| Popis: | Krokinobacter eikastus rhodopsin 2 (KR2) is a pentameric, light-driven ion pump, which selectively transports sodium or protons. The mechanism of ion selectivity and transfer is unknown. By using conventional as well as dynamic nuclear polarization (DNP)-enhanced solid-state NMR, we were able to analyse the retinal polyene chain between positions C10 and C15 as well as the Schiff base nitrogen in the KR2 resting state. In addition, 50% of the KR2 13C and 15N resonances could be assigned by multidimensional high-field solid-state NMR experiments. Assigned residues include part of the NDQ motif as well as sodium binding sites. Based on these data, the structural effects of the H30A mutation, which seems to shift the ion selectivity of KR2 primarily to Na+, could be analysed. Our data show that it causes long-range effects within the retinal binding pocket and at the extracellular Na+ binding site, which can be explained by perturbations of interactions across the protomer interfaces within the KR2 complex. This study is complemented by data from time-resolved optical spectroscopy. |
| Databáze: | OpenAIRE |
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