Table III.
Paramagnetic relaxation times of the protons of ligands bound to PD73His and corresponding calculated iron-proton distances
For each ligand, a complete titration was performed three times.
| Ligand | Parameter | Proton | ||||
|---|---|---|---|---|---|---|
| CA | H5/H4/H3 | H6/H2 | H3′ | H2′ | ||
| T1M(μs) | 239 ± 8 | 311 ± 31 | 796 ± 6 | 737 ± 11 | ||
| r(Å) | 5.76 ± 0.2 | 6.02 ± 0.6 | 7.04 ± 0.05 | 6.95 ± 0.1 | ||
| 3TA | H5 | H2 | H4 | H3′ | H2′ | |
| T1M(μs) | 949 ± 144 | 1,145 ± 138 | 560 ± 34 | 1,145 ± 107 | 997 ± 82 | |
| r(Å) | 7.25 ± 1.1 | 7.48 ± 0.9 | 6.64 ± 0.4 | 7.48 ± 0.7 | 7.31 ± 0.6 | |
| 2TA | H5 | H4 | H3 | H3′ | H2′ | |
| T1M(μs) | 1,127 ± 60 | 1,082 ± 117 | 941 ± 39 | 1,250 ± 49 | 1,310 ± 137 | |
| r(Å) | 7.46 ± 0.4 | 7.41 ± 0.8 | 7.24 ± 0.3 | 7.59 ± 0.3 | 7.65 ± 0.8 | |
| 4VB | Hb | Hc | Ha | H3/H5 | H2/H6 | |
| T1M(μs) | 663 ± 29 | 1,427 ± 257 | 699 ± 20 | 475 ± 29 | 420 ± 27 | |
| r(Å) | 6.83 ± 0.3 | 7.76 ± 1.4 | 6.89 ± 0.2 | 6.46 ± 0.4 | 6.33 ± 0.4 | |
| 4FC | H5/H3 | H6/H2 | H3′ | H2′ | ||
| T1M(μs) | 213 ± 15 | 217 ± 11 | 424 ± 33 | 493 ± 23 | ||
| r(Å) | 5.65 ± 0.4 | 5.67 ± 0.3 | 6.34 ± 0.5 | 6.50 ± 0.3 |