Solution deuterium NMR quadrupolar relaxation study of heme mobility in myoglobin
| العنوان: | Solution deuterium NMR quadrupolar relaxation study of heme mobility in myoglobin |
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| المؤلفون: | Kevin M. Smith, Daniel W. Parish, Kevin C. Langry, Gerd N. La Mar, Robert D. Johnson |
| المصدر: | Journal of the American Chemical Society. 111:481-485 |
| بيانات النشر: | American Chemical Society (ACS), 1989. |
| سنة النشر: | 1989 |
| مصطلحات موضوعية: | Deuterium NMR, Chemistry, Relaxation (NMR), General Chemistry, Nuclear magnetic resonance spectroscopy, Biochemistry, Catalysis, chemistry.chemical_compound, Crystallography, Colloid and Surface Chemistry, Nuclear magnetic resonance, Myoglobin, Proton NMR, Heme, Motional narrowing, Hyperfine structure |
| الوصف: | NMR spectroscopy has been used to monitor the quadrupolar relaxation and motional dynamics of {sup 2}H selectively incorporated into skeletal and side chain positions of the heme in sperm whale myoglobin. The hyperfine shifts of the heme resonances in paramagnetic states of myoglobin allow resolution of the signals of interest, and paramagnetic contributions to the observed line widths are shown to be insignificant. The {sup 2}H line widths for the skeletal positions of deuterohemin-reconstituted myoglobin yield a correlation time identical with that of overall protein tumbling (9 ns at 30{degree}C) and hence reflect an immobile heme group. The {sup 2}H NMR line widths of heme methyl groups exhibit motional narrowing indicative of very rapid internal rotation. Hence the methyl rotation is effectively decoupled from the overall protein tumbling, and the residual quadrupolar line width can be used directly to determine the protein tumbling rate. The {sup 2}H NMR lines from heme vinyl groups were found narrower than those from the heme skeleton. However, the range of quadrupolar coupling constants for sp{sup 2} hybridized C-{sup 2}H bonds does not permit an unequivocal interpretation in terms of mobility. 48 refs., 4 figs. |
| تدمد: | 1520-5126 0002-7863 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_________::aa5bcb51299b7399b5b397c115323e95 https://doi.org/10.1021/ja00184a013 |
| رقم الأكسشن: | edsair.doi...........aa5bcb51299b7399b5b397c115323e95 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15205126 00027863 |
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