دورية أكاديمية
Factors that differentiate the H-bond strengths of water near the Schiff bases in bacteriorhodopsin and Anabaena sensory rhodopsin.
| العنوان: | Factors that differentiate the H-bond strengths of water near the Schiff bases in bacteriorhodopsin and Anabaena sensory rhodopsin. |
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| المؤلفون: | Saito, Keisuke, Kandori, Hideki, Ishikita, Hiroshi |
| المساهمون: | 石北, 央 |
| بيانات النشر: | American Society for Biochemistry and Molecular Biology |
| سنة النشر: | 2012 |
| المجموعة: | Kyoto University Research Information Repository (KURENAI) / 京都大学学術情報リポジトリ |
| مصطلحات موضوعية: | Anabaena/chemistry, Bacteriorhodopsins/chemistry, Crystallography, X-Ray, Deuterium Oxide/chemistry, Hydrogen Bonding, Protein Structure, Tertiary, Schiff Bases |
| الوصف: | Bacteriorhodopsin (BR) functions as a light-driven proton pump, whereas Anabaena sensory rhodopsin (ASR) is believed to function as a photosensor despite the high similarity in their protein sequences. In Fourier transform infrared (FTIR) spectroscopic studies, the lowest O-D stretch for D(2)O was observed at ∼2200 cm(-1) in BR but was significantly higher in ASR (>2500 cm(-1)), which was previously attributed to a water molecule near the Schiff base (W402) that is H-bonded to Asp-85 in BR and Asp-75 in ASR. We investigated the factors that differentiate the lowest O-D stretches of W402 in BR and ASR. Quantum mechanical/molecular mechanical calculations reproduced the H-bond geometries of the crystal structures, and the calculated O-D stretching frequencies were corroborated by the FTIR band assignments. The potential energy profiles indicate that the smaller O-D stretching frequency in BR originates from the significantly higher pK(a)(Asp-85) in BR relative to the pK(a)(Asp-75) in ASR, which were calculated to be 1.5 and -5.1, respectively. The difference is mostly due to the influences of Ala-53, Arg-82, Glu-194-Glu-204, and Asp-212 on pK(a)(Asp-85) in BR and the corresponding residues Ser-47, Arg-72, Ser-188-Asp-198, and Pro-206 on pK(a)(Asp-75) in ASR. Because these residues participate in proton transfer pathways in BR but not in ASR, the presence of a strongly H-bonded water molecule near the Schiff base ultimately results from the proton-pumping activity in BR. |
| نوع الوثيقة: | article in journal/newspaper |
| وصف الملف: | application/pdf |
| اللغة: | English |
| تدمد: | 0021-9258 22865888 |
| العلاقة: | http://hdl.handle.net/2433/169708Test; AA00251083; The Journal of biological chemistry; 287; 41; 34009; 34018 |
| الإتاحة: | http://hdl.handle.net/2433/169708Test |
| حقوق: | This research was originally published in "Journal of Biological Chemistry". Saito K., Kandori H., Ishikita H. Factors that differentiate the H-bond strengths of water near the schiff bases in bacteriorhodopsin and Anabaena sensory rhodopsin. 2012;287:34009-34018. © the American Society for Biochemistry and Molecular Biology. ; This is not the published version. Please cite only the published version. ; この論文は出版社版でありません。引用の際には出版社版をご確認ご利用ください。 |
| رقم الانضمام: | edsbas.F9407986 |
| قاعدة البيانات: | BASE |
Full Text Finder | تدمد: | 00219258 22865888 |
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