Effect of the detergents SDS, CHAPS, and Triton X-100 on tomato plasma membrane NADPH oxidase activity1-a
| Treatment | Concentration | Relative Activity |
|---|---|---|
| μM and % | % ± se | |
| No detergent | 0 | 100 ± 6 |
| SDS | 40 (0.0012%) | 85 ± 5 |
| 100 (0.0029%) | 54 ± 4 | |
| 200 (0.0058%) | 36 ± 4 | |
| 3,467 (0.1%) | 0.8 ± 2 | |
| 34,674 (1%) | 0 | |
| CHAPS | 1,626 (0.1%) | 75 ± 7 |
| 16,263 (1%) | 25 ± 5 | |
| 32,526 (2%) | 21 ± 7 | |
| Triton X-100 | 15,480 (1%) | 33 ± 5 |
↵F1-a Membrane fractions were obtained from the upper phase of aqueous two-phase partitioning. The superoxide production (reduction of 2, 3-bis [2-methoxy-4-nitro-5-sulfophenyl 2H-tetrazolium-5-carboxanilicle [XTT]]) was quantified as described in “Materials and Methods.” The activity is expressed as percentage of control values without detergents (100% = 0.395 ± 0.027 of XTT formazan absorbance at 470 0.6 h−1 3 μg−1 plasma membrane protein). Means and seare calculated for two to three independent plasma membrane preparations.