Figure 4.

Chemical unfolding and refolding studies. (A) Gdn-HCl induced denaturation and renaturation of nJacalin as well as rJacalin (0.6 μM) at 30°C monitored by the fluorescence of Trp at required Gdn-HCl concentration. Protein sample was incubated for 4 h prior to measurements. The fluorescence spectra were recorded between 300 nm and 400 nm with the excitation wavelength of 280 nm. The percent residual activity after incubation of protein at a given concentration of Gdn-HCl was determined as described in the Materials and Methods section. For renaturation, the samples were diluted 10 times in phosphate buffer and incubated for 1 h at 30°C, spectra were observed, and activity was assessed. The symbols used in this figure are nJacalin denaturation (○), nJacalin renaturation (□), rJacalin denaturation (•), rJacalin renaturation (▪). (B) Denaturation by Gdn-HCl, ratio F(334/356). The symbols used are nJacalin (○) and rJacalin (•).