The secondary structure of bacteriorhodopsin in organic solution

Fourier transform infrared spectroscopy is used to estimate the secondary structure of bacteriorhodopsin dissolved in Chloroform‐methanol (1:1 v/v), 0.1 M LiClO 4 . Curve‐fitting of the deconvolved spectra in the amide I region shows that the total content of α‐helices, reverse turns and β‐sheets are similar to the native state. However, the α II ‐helices, which are the major helical class in native bacteriorhodopsin, are greatly decreased in the solubilized sample. Similarly, the reverse turns and the β‐sheets are strongly altered.