Figure 4.
(A) The dose-dependent effect of rMaspin(i) (○) and trypsin-cleaved maspin (•) on the plasminogen activation by fibrinogen/gelatin-activated sctPA. Dashed lines represent calculated initial velocities by using Eq. 2 with α = 0.21, β = 1.45 × 10−7/min, ξ = 0.1, ψ = 6.0 × 10−8 pM−1, and ζ = 1.0 × 10−16 pM−2 for rMaspin(i), and α = 1.01, β = 1.727 × 10−6/min, ξ = 0.425, ψ = 1.7 × 10−7 pM−1, and ζ = 1.0 × 10−16 pM−2 for trypsin-cleaved maspin. (B) Double-reciprocal plot of 1/v vs. 1/s for the plasminogen activation by fibrinogen/gelatin-activated sctPA at low concentrations of rMaspin(i). The substrate, S, is plasminogen. (C) Replot of the slopes of the double-reciprocal plot vs. the concentration of rMaspin(i). The intercept on the horizontal axis indicates the Ki value as 0.13 μM. The initial velocities are presented as rate of the production of plasmin in units of pM/min. The error bars represent the standard deviations of two parallel experiments.