Conformational states of human H-Ras detected by high-field EPR, ENDOR, and 31P NMR spectroscopy
Copyright 2005 John Wiley & Sons, Ltd
| Veröffentlicht in: | Magnetic resonance in chemistry : MRC. - 1985. - 43 Spec no.(2005) vom: 15. Nov., Seite S74-83 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , , , |
| Format: | Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2005
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| Zugriff auf das übergeordnete Werk: | Magnetic resonance in chemistry : MRC |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Ligands Nucleotides Phosphorus Isotopes Solutions ras Proteins EC 3.6.5.2 |
| Zusammenfassung: | Copyright 2005 John Wiley & Sons, Ltd Ras is a central constituent of the intracellular signal transduction that switches between its inactive state with GDP bound and its active state with GTP bound. A number of different X-ray structures are available. Different magnetic resonance techniques were used to characterise the conformational states of the protein and are summarised here. 31P NMR spectroscopy was used as probe for the environment of the phosphate groups of the bound nucleotide. It shows that in liquid solution additional conformational states in the GDP as well as in the GTP forms coexist which are not detected by X-ray crystallography. Some of them can also be detected by solid-state NMR in the micro crystalline state. EPR and ENDOR spectroscopy were used to probe the environment of the divalent metal ion (Mg2+ was replaced by Mn2+) bound to the nucleotide in the protein. Here again different states could be observed. Substitution of normal water by 17O-enriched water allowed the determination of the number of water molecules in the first coordination sphere of the metal ion. In liquid solution, they indicate again the existence of different conformational states. At low temperatures in the frozen state ENDOR spectroscopy suggests that only one state exists for the GDP- and GTP-bound form of Ras, respectively |
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| Beschreibung: | Date Completed 22.12.2005 Date Revised 15.11.2006 published: Print Citation Status MEDLINE |
| ISSN: | 1097-458X |