. Titrations with SDS orLiDS show that a secondary structure conversion ofAb(1–40) can be described essentially as a two-stateprocess, involving conversion of the initial weak struc-ture to b-sheet-rich. detergent⁄ peptide (D⁄ P) ratios of0.7–267, respectively. The CD data report on a firststructural conversion from a mixture of ppII helix andrandom coil (weak positive shoulder at approximately220. (3.0 mm LiDS,D ⁄ P = 40), a new state is observed, mostly consistingof a-helix structure. The conversion to a-helix struc-ture reached its final state at 20 mm LiDS with a char-acteristic maximum...