Table 1.
Cys mutant | EFRETa | R (Å)b | R0 (Å)c | |
---|---|---|---|---|
SP22 data | 190 | 0.70 | 29.2±0.5 | 33.7 |
213 | 0.21 | 42.3±0.2 | 32.4 | |
256 | 0.53 | 26.1±0.2 | 26.7 | |
287 | 0.70 | 26.2±0.2 | 30.3 | |
292 | 0.33 | 30.8±1.1 | 27.5 | |
371 | 0.35 | 37.8±0.5 | 30.6 | |
402d | 0.08 | 58.3±2.1 | 39.5 | |
447d | 0.15 | 52.8±1.8 | 39.5 | |
470d | 0.16 | 51.8±1.9 | 39.5 | |
506 | 0.10 | 49.1±1.2 | 34.0 | |
661 | 0.53 | 33.9±3.9 | 33.7 | |
718 | 0.36 | 37.3±0.1 | 40.6 | |
827 | 0.21 | 42.4±0.2 | 33.7 | |
SP2 data | 190 | 0.59 | 32.1±0.7 | 33.7 |
213 | 0.66 | 30.5±0.2 | 32.4 | |
256 | 0.53 | 39.4±0.3 | 33.7 | |
292 | 0.63 | 31.1±0.2 | 27.5 | |
827 | 0.50 | 33.9±0.1 | 33.7 |
FRET efficiency (EFRET) was measured by the quenching of the donor fluorescence intensity as described in Experimental Procedures.
The donor–acceptor distance (R) was calculated as described in Experimental Procedures.
The Förster energy transfer distance defined as 50% efficient.
The FRET fluorescent dye pair used included Alexa Fluor-488 and Alexa Fluor-555.