TABLE I.
Kinetic parameters obtained from kinetic analysis of TRXSS data of T72V HbI.
| Parameter | Fit value | Error |
|---|---|---|
| Time constant for I1-to-I2 transition | 3.1 ns | 0.4 ns |
| Time constant for geminate recombination | 140 ns | 80 ns |
| Faster time constant for R-T transition (τRT1) | 490 ns | 600 nsa |
| Slower time constant for R-T transition (τRT2) | 980 ns | 1 μsa |
| Time constant for formation of ligated I1 | 39 μs | 20 μs |
| Rate constant for bimolecular CO recombination | 310 mM−1s−1 | 7 mM−1s−1 |
| Fraction of geminate recombination | 26% | 0.8% |
| Fraction of fully photolyzed forms | 82% | 3% |
a
The error values of τRT1 and τRT2 for the T72V mutant are relatively large, because the values of τRT1 and τRT2 are close to each other. In fact, it is possible to approximate the kinetics of R-T transition for the T72V mutant even by a single exponential.