Backbone motion in elastin's hydrophobic domains as detected by ²H NMR spectroscopy

The elasticity of vertebrate tissue originates from the insoluble, cross-linked protein elastin. Here, the results of variable-temperature ²H NMR spectra are reported for hydrated elastin that has been enriched at the Hα position in its abundant glycines. Typical powder patterns reflecting averaged quadrupolar parameters are observed for the frozen protein, as opposed to the two, inequivalent deuterons that are detected in a powder sample of enriched glycine. The spectra of the hydrated elastin at warmer temperatures are dominated by a strong central peak with features close to the baseline, reflective of both isotropic and very weakly anisotropic motions.