as indicated by greater loss in peak volume for rigid residues than partially mobile residues. The greatest mobility was observed in the CypA binding loop, consistent with our own results. 15N–15N backbone dipolar recoupling (15N-BARE) experiments were utilized for the measurement of the torsion angles wi and wi1 (and ui to an extent).
While
most a-helical residues exhibited rapid dephasing due to relatively
short interhelical distances, some residues displayed slower dephasing times, indicative of extended backbone conformations,