Time kinetics of proteolytic processing of PBP and CTAP-III on coincubation with purified cathepsin G.

Cathepsin G (1 μg/mL) was coincubated with 500 nmol/L of either NAP-2 precursor for the time periods indicated, and supernatants (SNs) were taken and analyzed exactly as reported in the legend to Figure 3A. (A) Western blot analysis of SN: 10 μL of each SN was separated by SDS-PAGE, blotted, and subsequently immunostained with antiserum Rα-βTG. 50 ng NAP-2 was run in parallel for comparison. Data from 1 of 3 representative experiments are shown. N, NAP-2; P, PBP; C, CTAP-III. (B) Determination of NAP-2 activity equivalents in SN (compare with legend to Figure 3B). Shown are means ± SD of data obtained in 3 independent experiments. ●, CTAP-III (500 nmol/L); ▴, PBP, (500 nmol/L).