Figure 3.

Secondary structure, thermal stability and thermal activity profile analyses of WT and mutant I-AniI variants. (A) Circular dichroism analysis. Far-UV CD spectra were measured between 190 and 260 nm at 25°C. (B) Temperature-dependent denaturation on the basis of changes in circular dichroism ellipticity at 222 nm. Temperature of 50% transition was 53.9, 52.6 and 43.5°C for WT, Y2 variant and M5 variant, respectively. (C) Thermal profiles of the cleavage activity. The reactions ran at 22, 30, 37, 42, 47, 55 and 65°C. Relative activity was shown by taking cleavage activity at 47°C as 100%. Errors mean ± S.D.