PMC:2728246 / 42917-44147 JSONTXT

{"target":"https://pubannotation.org/docs/sourcedb/PMC/sourceid/2728246","sourcedb":"PMC","sourceid":"2728246","source_url":"https://www.ncbi.nlm.nih.gov/pmc/2728246","text":"Most striking, however, is the observation of in all available cases as seen in Fig. 4e, f. The obvious interpretation is that the rotameric jump model only explains part of the mobility experienced by the Cβ–Cγ bond. Just like the ratio defines the temporally distinct supra-τc order parameters, the ratio could define a geometrically distinct libration order parameter around the equilibrium positions. For instance, I30(Cγ1) is predicted to mostly sample a single rotamer with the gauche− rotamer dominating the χ1 distribution, based on . This same methyl group is however, quite mobile based on (0.48 ± 0.20). Interestingly, the backbone at that position over the same time scale is relatively flexible based on (NH) = 0.78, which would suggest that some of the mobility would be due to “wobbling” of the Cα–Cβ bond with the backbone. Nevertheless, for other residues where the Cγ undergo significant rotameric interconversions, is exquisitely sensitive to supra-τc motions. Notably, the were significantly lower than the (CC) for several residues in the first pair of ubiquitin’s anti-parallel β-strand, indicating that rotameric averaging on a time scale slower than the rotational correlation time is taking place.","tracks":[]}