Wideline Separation (WISE) NMR of Native Elastin

Abstract

Native elastin is an insoluble, amorphous (noncrystalline) protein with significant hydrophobic character. As its name suggests, the elasticity of blood vessels and other tissue types in vertebrates originates from this protein. We have previously shown that there is significant structural heterogeneity in this protein and its mimetics, and our earlier data indicated that its dynamic profile includes motions under multiple time scales. To examine this picture further, we use WIdeline SEparation (WISE) NMR experiments to characterize the natural-abundance 13C populations of unenriched elastin in fully hydrated and lyophilized states. The hydrated elastin has only one peak in the indirect dimension, reflective of significant motional narrowing. In contrast, the lyophilized elastin has a broad feature, indicating limited or no motion. In addition, however, our results indicate that a faster motion is also present, even in the absence of the water. The details of the line fitting and the possible implications...