The substrate has the following kinetic constants for βI tryptase: kcat of 17.84  ± 0.40s-1, km of  14.5  ± 1.9 μm,    kcat/Km  of (1.23  ± 0.15) × 106 s−1 m−1. 

The substrate has the following kienetic constants for  βII tryptase: kcat of 16.84  ± 0.27s-1, km of  8.9  ± 0.9 μm, kcat/Km  of (1.89  ± 0.17) × 106 s−1 m−1.