... structure of RNase A coinciding with the loss of its enzymatic activity. In contrast to the dena-turation by guanidine hydrochloride, urea or temperature, the breakdown of the tertiary structure in ... CD spectra in the far-UV region, on the other hand, indicate a detectableincrease in the content of secondary structure only after the disruption of the native tertiary structure of RNase A(Figs ... guanidine hydro-chloride (GdnHCl), urea or elevated temperatures, theydestroy the tertiary structure of proteins which results in the loss of enzymatic activity. Regarding the secondary struc-ture...