ISSN:
0006-3525
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
To attempt to resolve the controversy over “fast” and “slow” helix-coil transition rates in polypeptides, nuclear magnetic resonance spectra were measured for monodisperse poly-γ-benzyl-L-glutamate (PBLG). These results were compared with simulated line spectra which were computed by taking the molecular-weight distribution into consideration. Broad but single peaks have been observed in 220 mHz nmr for the α-CH and NH proton resonance spectra in the transition region. The shape of the line changes with the extent of polydispersity. Assuming a fast conversion rate, a molecular model of the helix-coil transition simulates these results. Consequently, the double peak which has been observed in the nmr of polypeptides at the helix-coil transition region is shown to result from the polydispersity in molecular weight.
Additional Material:
11 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/bip.1973.360121102
