*4.5. CD and FTIR Experiments*

CD and FTIR analyses were performed as previously described [43]. In particular, Far-UV CD spectra of 20 μM AS in PBS buffer were acquired on a J-815 spectropolarimeter (JASCO Corp., Tokyo, Japan) under the following instrumental settings: data pitch, 0.1 nm; scan speed, 20 nm/min; bandwidth, 1 nm; accumulation spectra, 2. A 1-mm path length quartz cuvette was employed. FTIR spectra of 340 μM AS in deuterated PBS buffer were acquired on a Varian 670-IR spectrometer (Varian Australia Pty. Ltd., Mulgrave, VIC, Australia) under the following instrumental settings: resolution, 2 cm<sup>−</sup>1; scan speed, 25 kHz; scan coadditions, 1000; apodization, triangular; nitrogen-cooled mercury cadmium telluride detector. A temperature-controlled transmission cell with two BaF2 windows separated by a 100-μm Teflon spacer was employed. Representative spectra from three independent experiments are shown.
