Analyses on structural transition of peptide amphiphile micelles with small angle neutron scattering and circular dichroism

Sakamoto, Naoki*; Shimada, Tomoko*; Motokawa, Ryuhei   ; Koizumi, Satoshi*

Peptide amphiphile (PA) micelles are unique materials, whose morphologies are controlled by the peptide secondary structure as well as the length of the peptide and alkyl chains. The dynamics of the thermally-induced structural transition of our designed PA micelles was investigated by in situ small-angle neutron scattering (SANS) and Circular Dicroism (CD). The results revealed the time-evolution of the peptide secondary structure and the micellar morphology after temperature-jump. We propose the mechanism of these cooperative transitions: the change of the peptide secondary structure from a-helix and random coil to B-sheet induces the micellar structural transition from the spherical to the worm-like.