Table 2. Calculated and Experimental Hyperoxidation Sensitivity of Tsa1, Human Prxs, and AhpC.
| Prx | Tsa1A177S A178D | Tsa1 | Tsa1W161F | Tsa1 | Tsa1 |
|---|---|---|---|---|---|
| peroxide | H2O2 | H2O2 | H2O2 | tBOOH | CuOOH |
| kLU (s–1) | 216 ± 42 | 64 ± 5 | 37 ± 1 | 59 ± 6 | 57 ± 5 |
| k4a (M–1 s–1) | 103 ± 400 | (2.1 × 103) ± 200 | (2.9 × 103) ± 70 | (9.5 × 103) ± 200 | (39 × 103) ± 500 |
| calculated Chyp1% (μM) | 2160 ± 1280 | 305 ± 53 | 128 ± 7 | 62 ± 8 | 16 ± 1 |
| experimental Chyp1% (μM) | 2620 ± 220 | 730 ± 100 | 440 ± 93 | 63 ± 15 | 11 ± 2 |
| Prx | hPrx1 | hPrx1 | hPrx2 | hPrx3 | AhpC |
|---|---|---|---|---|---|
| peroxide | H2O2 | ONOOH | H2O2 | H2O2 | H2O2 |
| kLU (s–1) | 10.8 ± 2 | 10.8 ± 2 | 0.2–0.612,13,16 | 2011 | >205 calculated |
| k4a (M–1 s–1) | 1.77 × 103 12 | 2.8 × 105 12 | (1.73–1.97) × 103 12,16 | 2 × 103 estimated | 41012 |
| calculated Chyp1% (μM) | 61 ± 13 | 0.4 | 1–3 | 100 | |
| experimental Chyp1% (μM) | 80 ± 5/5018 | 518 | 12727 | >500018 |
a
Measured on C171A mutants. Data are reported as the mean value obtained from two independent experiments performed on distinct protein productions ± s.d.