Thermal unfolding in presence of Sodium halides. Thermal denaturation profile at pH 8.5 in presence of 200 mM NaCl (panel A), NaF (panel B) and at pH 6 in presence of 200 mM NaCl (panel C) and NaF (panel D), respectively. The open and closed circles represent CD ellepticity measured at 222 nm and 415 nm, respectively. A linear extrapolation of baselines in pre and post transition regions was used to determine the fraction unfolded protein within the transition region by assuming a two state mechanism of unfolding. The thermal transition of the enzyme was found to be irreversible with precipitation observed at the end of the scan.