Table 1.
Experimental pulsed (electron) dipolar spectroscopy (PDS) and calculated PRONOX distances in doubly spin-labeled soybean seed lipoxygenase-1 mutants
| SDSL pair | PDS distance (Å)∗ | PRONOX distances (Å)† |
|---|---|---|
| 270-480 | 32.5 | 30.1 ± 0.5 |
| 270-569 | 37 | 37.6, 39.5 ± 0.2, 40.3 ± 0.9 |
| 270-619 | 47 | 48.5 |
| 270-782 | 38 | 41.8 |
| 480-569 | 37.5 | 37.4 ± 0.1, 39.6 ± 0.4, 39.9 ± 0.5 |
| 480-619 | 46.5 | 46.0 ± 0.5 |
| 480-782 | 52.5 | 52.0 ± 0.7 |
| 569-619 | 44 | 39.7, 41.3 ± 1.4, 49.9 ± 0.8 |
| 569-782 | 44/52 | 47.3, 48.7 ± 0.7, 48.9 ± 1.1 |
| 619-782 | 20/22 | 22.0 |
SDSL, site-directed spin label.
Experimental distances are the maxima in the distance distributions shown in Fig. 3. The corresponding maxima in Fig. 5 are LOPTC spin to F270R1 (23 and 30 Å), L480R1 (43 Å), A569R1 (38 Å), A619R1 (47 Å), and F782R1 (37.5 Å). The distance between residues A619R1 and F782R1 showed two close peaks, but a single value of 22 Å was used in calculations of the LOPTC spin location.
Calculated interspin distances are the average of the distance between N-N and O-O. Multiple acceptable PRONOX fits of the spin label at L480R1 and A569R1 were found, of 2 and 10, respectively. Average distances and their standard deviations are given for pairs involving these sites.