TABLE 2.
Parameters associated with fluorescence intensity decays
The time-resolved fluorescence intensity decays of all the denatured samples fitted satisfactorily to a three-exponential function (Equation 1). The fluorescence lifetimes (τ) and their amplitudes (α) as well as the mean fluorescence lifetime (τm) values derived from the fitting are shown. The error associated with fluorescence lifetime measurement and its amplitude is ∼5–10%. The error associated with τm is <5%.
| Sample | τ1 (ns) (α1) | τ2 (ns) (α2) | τ3 (ns) (α3) | τm (ns) |
|---|---|---|---|---|
| [V3W]WT + 6 m GdnHCl | 0.25 (0.19) | 0.98 (0.28) | 2.48 (0.53) | 1.64 |
| [V71W]WT + 6 m GdnHCl | 0.32 (0.19) | 1.10 (0.36) | 3.53 (0.45) | 2.05 |
| [A124W]WT + 6 m GdnHCl | 0.26 (0.15) | 1.18 (0.36) | 3.17 (0.49) | 2.02 |
| [A140W]WT + 6 m GdnHCl | 0.21 (0.12) | 1.42 (0.19) | 4.99 (0.69) | 3.74 |
| [V3W]E46K + 6 m GdnHCl | 0.21 (0.54) | 1.2 (0.22) | 3.8 (0.24) | 1.29 |
| [V71W]E46K + 6 m GdnHCl | 0.34 (0.33) | 1.54 (0.33) | 4.02 (0.34) | 1.99 |
| [A124W]E46K + 6 m GdnHCl | 0.24 (0.2) | 1.39 (0.36) | 3.33 (0.44) | 2.01 |
| [A140W]E46K + 6 m GdnHCl | 0.65 (0.26) | 3.42 (0.34) | 5.71 (0.4) | 3.62 |
| [V3W]A53T + 6 m GdnHCl | 0.29 (0.29) | 1.49 (0.4) | 3 (0.31) | 1.61 |
| [V71W]A53T + 6 m GdnHCl | 0.34 (0.33) | 1.43 (0.33) | 3.94 (0.34) | 1.92 |
| [A124W]A53T + 6 m GdnHCl | 0.34 (0.21) | 1.39 (0.34) | 3.28 (0.45) | 2.02 |
| [A140W]A53T + 6 m GdnHCl | 0.46 (0.24) | 3.19 (0.28) | 5.59 (0.48) | 3.69 |
| [V3W]A30P + 6 m GdnHCl | 0.21 (0.22) | 1.23 (0.36) | 2.8 (0.42) | 1.67 |
| [V71W]A30P + 6 m GdnHCl | 0.33 (0.33) | 1.41 (0.33) | 3.93 (0.34) | 1.91 |
| [A124W]A30P + 6 m GdnHCl | 0.19 (0.12) | 1.1 (0.37) | 3.19 (0.51) | 2.06 |
| [A140W]A30P + 6 m GdnHCl | 0.48 (0.24) | 3.18 (0.28) | 5.56 (0.48) | 3.67 |