Figure 10.

Aprotinin only inhibits monomeric β-tryptase. Relative enzymatic activity of tetrameric WT and monomeric mutant (I99C*/Y75A/Y37bA) β-tryptases in the presence or absence of 10 μm aprotinin is shown. Activities were determined in TNH buffer with 1 mm S-2288. Tetramer activity was assayed at 1 nm and normalized to 1 nm WT; monomer activity was assayed at 100 nm and normalized to 100 nm mutant monomer. Data were collected in triplicate; errors are shown as S.D.