NMR Ensembles of Models: Difference between revisions
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The '''variation between models''' in the ensemble can mean either of two things. The variation can represent actual '''flexibility and thermal motion''' that occurred during the NMR measurements in solution, typically at room temperature. Alternatively, the variation can simply mean '''uncertainty in the atomic positions''', namely, that an inadequate number of restraints were available to determine the positions of some atoms. Unfortunately, there is nothing comparable to the ''B factor'' or ''temperature value'' that quantitates the uncertainty of the position of each atom in crystallographic results. Hence, the only way to find out what the meaning of the variation between models is to contact the experimenters who authored the published ensemble of models. | The '''variation between models''' in the ensemble can mean either of two things. The variation can represent actual '''flexibility and thermal motion''' that occurred during the NMR measurements in solution, typically at room temperature. Alternatively, the variation can simply mean '''uncertainty in the atomic positions''', namely, that an inadequate number of restraints were available to determine the positions of some atoms. Unfortunately, there is nothing comparable to the ''B factor'' or ''temperature value'' that quantitates the uncertainty of the position of each atom in crystallographic results. Hence, the only way to find out what the meaning of the variation between models is to contact the experimenters who authored the published ensemble of models. | ||
==Reliability of NMR Models== | |||
NMR models are more likely to contain major errors <ref>Traditional biomolecular structure determination by NMR spectroscopy allows for major errors. Sander B. Nabuurs, Chris. A. E. M. Spronk, Geerten W. Vuister, and Gert Vriend. (2006). PLoS Computational Biology 2: Open Access Full Text. DOI: 10.1371/journal.pcbi.0020009</ref> than are crystallographic models that have good [[Resolution]] and [[Free R]] values. | |||
==The Most-Representative Model== | ==The Most-Representative Model== | ||
