Abstract
The time scale of internal motion of the Ala 3-Leu 4 peptide linkage plane of gramicidin A in its channel conformation is analyzed by interpreting solid-state 15N T 1 measurements taken at 4.7 and 9.4 T. The T 1 relaxation measurements have been interpreted using a structural model of local motion which has previously been experimentally determined. According to this model, the individual peptide plane motion is a rotational diffusion subject to a harmonic restoring potential about an axis through successive α carbons. The results which best fit the model to the data reported here and to previously determined information about the motions of the gramicidin channel suggest that the correlation time for librations of the Ala 3-Leu 4 peptide linkage is 36 ns. This suggests that the peptide backbone motions of the gramicidin channel may be on the same time scale as the translational motion of a cation in the channel.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
