2H NMR study of molecular motion in collagen fibrils.

Collagen was labelled through tissue culture with [3,3,3-d3]alanine. 2HNMR spectra were obtained of the labelled collagen as fibrils and in solution using the quadrupolar echo technique for solids. The 2H NMR data were analysed in terms of a model for reorientation in which the molecule is considered to jump between two orientations in a time which is short compared to the residence time in each site, and short compared to (delta vq)-1. The best fit of the data indicates that the collagen molecule in the fibrils experiences reorientation about its long axis over an angular range of approximately 30--40 degrees. The T2 for [3,3,3-d3]alanine-labelled collagen fibrils is estimated to be approximately 110 mus.