Single molecule kinetics of bacteriorhodopsin by HS-AFM
| العنوان: | Single molecule kinetics of bacteriorhodopsin by HS-AFM |
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| المؤلفون: | Perrino, Alma P., Miyagi, Atsushi, Scheuring, Simon |
| المصدر: | Nature Communications, Vol 12, Iss 1, Pp 1-10 (2021) Nature Communications |
| بيانات النشر: | Nature Portfolio, 2021. |
| سنة النشر: | 2021 |
| مصطلحات موضوعية: | Cytoplasm, Ion Transport, Multidisciplinary, Light, Protein Conformation, Science, Biophysics, General Physics and Astronomy, General Chemistry, Hydrogen-Ion Concentration, Molecular Dynamics Simulation, Proton Pumps, Microscopy, Atomic Force, Article, Single Molecule Imaging, General Biochemistry, Genetics and Molecular Biology, Membrane biophysics, Atomic force microscopy, Kinetics, Single-molecule biophysics, G protein-coupled receptors, Bacteriorhodopsins, Receptors, Opioid, Nanotechnology |
| الوصف: | Bacteriorhodopsin is a seven-helix light-driven proton-pump that was structurally and functionally extensively studied. Despite a wealth of data, the single molecule kinetics of the reaction cycle remain unknown. Here, we use high-speed atomic force microscopy methods to characterize the single molecule kinetics of wild-type bR exposed to continuous light and short pulses. Monitoring bR conformational changes with millisecond temporal resolution, we determine that the cytoplasmic gate opens 2.9 ms after photon absorption, and stays open for proton capture for 13.2 ms. Surprisingly, a previously active protomer cannot be reactivated for another 37.6 ms, even under excess continuous light, giving a single molecule reaction cycle of ~20 s−1. The reaction cycle slows at low light where the closed state is prolonged, and at basic or acidic pH where the open state is extended. Here, the authors use high-speed atomic force microscopy (HS-AFM) methods to characterize the single molecule kinetics of wild-type bacteriorhodopsin (bR) with millisecond temporal resolution, providing new insights into the bR conformational cycle. |
| اللغة: | English |
| تدمد: | 2041-1723 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::318367eb2cc3e7ccd6a60c6cffaffb3eTest https://doaj.org/article/8cb3eaef9fad4202a1ed7133ccef787eTest |
| حقوق: | OPEN |
| رقم الانضمام: | edsair.doi.dedup.....318367eb2cc3e7ccd6a60c6cffaffb3e |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 20411723 |
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