Far-UV CD spectra were recorded on a JASCO J-815
spectropolarimeter (Jasco Corporation, Tokyo, Japan)
equipped with a Peltier-type temperature controller and a
thermostated cell holder, interfaced with a thermostatic
bath at 25C using a cell with a path length of 0.1 cm.
Typical spectral accumulation parameters were a
scanning rate of 50 nm/min with a 2 nm bandwidth over
the wavelength range 200–250 nm with six scans
averaged for each far-UV spectrum using a protein
concentration of 10–15 μM in 10 mM Tris–HCl and pH
7.5. The CD data are presented in terms of mean residue
ellipticity (MRE, expressed as deg cm2 dmol−1) as a
function of wavelength, using the following equation: