[Inhibition of cathepsin G and elastase from human granulocytes by multiple forms of the Bowman-Birk type of soy inhibitor].

A classical soybean inhibitor (Bowman-Birk inhibitor, BBI 2-IV) and two high molecular weight glycine-enriched inhibitors of the same type (3-II and 4-II) have been isolated, purified to homogeneity and characterized. All of the BBI isoforms have been found to effectively inhibit cathepsin G and human granulocyte elastase. The constants for leucocyte cathepsin G inhibition by classical BBI 2-IV (Ki = 1.2 x 10(-9) M) and high molecular mass BBI 3-II (Ki = 8.0 x 10(-8) M) as well as for leucocyte elastase inhibition by high molecular mass BBI 3-II (Ki = 1.1 x 10(-7) M) have been determined.