Kinetics of the helix-coil transition of a polypeptide with non-ionic side groups, derived from ultrasonic relaxation measurements.
Ultrasonic absorption and velocity dispersion curves have been measured in the temperature induced helix-coil transition range of poly-N5-(3-hydroxypropyl)-L-glutamine in a methanol/water mixture. The results clearly reflect an effect due to the kinetics of the conformational conversion. A practically single relaxation time is observed which passes through a maximum when plotted versus the degree of transition. This maximum occurs at definitely less than 50% helix as predicted for by the theory for the comparatively short chain length involved here. The results are discussed in relation to previous theoretical and experimental findings.
D002151:Calorimetry; D007700:Kinetics; D008968:Molecular Conformation; D010455:Peptides; D013816:Thermodynamics; D014465:Ultrasonics
D010455:Peptides