TABLE 2.
Results from fluorescent lifetime measurements for the investigation of ESPT
| GFP mutant | λdet (nm) | τ1 (ps) | A1 (%) | τ2 (ps) | A2 (%) | τ3 (ns) | A3 (%) |
|---|---|---|---|---|---|---|---|
| T203V | 460 | 71 (12) | 68 (5) | 422 (76) | 25 (3) | 1.21 (0.20) | 7 (2) |
| 515 | 111 (33) | −5 (4) | — | — | 3.29 (0.06) | 100 (1) | |
| T203V (D2O) | 460 | 112 (11) | 79 (5) | 463 (133) | 15 (4) | 1.49 (0.22) | 6 (2) |
| 515 | 90 (19) | −56 (14) | — | — | 3.32 (0.07) | 100 (1) | |
| S65G/E222Q | 460 | — | — | 200 (180) | 37 (16) | 1.15 (0.10) | 63 (10) |
| 515 | — | — | 370 (260) | 40 (18) | 1.27 (0.26) | 60 (23) | |
| S65G/E222Q (D2O) | 460 | — | — | 200 (200) | 33 (16) | 1.14 (0.09) | 67 (19) |
| 515 | — | — | — | — | 1.06 (0.06) | 100 | |
| S65G/E222Q T = 2 K* | 445 | — | — | — | — | 2.67 (0.09) | 100 |
| 465 | — | — | — | — | 2.71 (0.11) | 100 | |
| 480 | — | — | — | — | 2.53 (0.07) | 100 | |
| 503 | — | — | — | — | 2.51 (0.08) | 100 | |
| S65G/T203V/E222Q | 460 | — | — | 432 (79) | 33 (4) | 1.38 (0.04) | 67 (3) |
| 515 | — | — | 400 (78) | 37 (3) | 1.39 (0.04) | 63 (4) | |
| S65G/T203V/E222Q (D2O) | 460 | — | — | 455 (52) | 37 (3) | 1.39 (0.03) | 63 (4) |
| 515 | — | — | 395 (90) | 36 (4) | 1.37 (0.06) | 64 (6) |
The data were collected with a TCSPC setup using an excitation wavelength λexc = 390 nm (*λexc = 420 nm). If not stated otherwise, the experiments were performed in aqueous buffer at room temperature. D2O was used as a solvent to monitor a slowdown of ESPT due to an isotope effect. Values given in parentheses represent the standard error.