Figure 4.

Activity of 2-Cys PRX B with various Trxs as proton donors. The enzyme (20 μm) 2-Cys Prx B was incubated with 400 μm DTT, 400 μm t-BOOH, and 10 μm Trx. The reduction of t-BOOH was measured by colorimetric titration and expressed as the remaining percentage of unreduced reagent. Control without Trx (⋄) or with Trx f1 (□), m1 (○), y1 (▿), y2 (▾), and x (▵). The actual initial rates of reduction, expressed in μmoles t-BOOH reduced min⁻¹ μmol⁻¹ Prx were, respectively, 0.37 (without Trx), 0.78 (Trx y1 or y2), 1.25 (Trx m1 or f1), and 10.00 (Trx x).