Abstract
The helix—coil transition of a polypeptide is investigated for the case in which a tensile force is applied at the chain ends. The free energy is calculated by the use of a Green’s function which was first introduced by de Gennes. The helix content, the mean end-to-end vector, and the mean length of the helical sequences are calculated as functions of the external force. It is found that in the coil region, the helical sequences continue to break as the external force increases. However, in the helix region, the external force first winds the polypeptide and produces longer helical sequences, but when the force becomes strong enough, the helical sequences break abruptly, and finally the polypeptide is brought to the random coil state.
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Doi, M. Helix—Coil Transition under External Forces. Polym J 6, 222–229 (1974). https://doi.org/10.1295/polymj.6.222
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DOI: https://doi.org/10.1295/polymj.6.222