Fig. 2.

SDS-PAGE analysis of complex formation with thrombin by the S1C mutants of α₁-antitrypsin. α₁-AT was mixed with thrombin in a 2:1 molar ratio and allowed to incubate for 30 min at 25°C, following which the complexes were analyzed by 10% SDS-PAGE. The mutants analyzed are indicated, with P6′–P9′ mutants and wild type analyzed in (A), while the P10′ mutant is shown in (B). Incubation with thrombin (+) or not (−) is indicated . The positions of complexed, intact, and cleaved α₁-AT, as well as thrombin alone, are indicated. The molecular weight markers are shown in lanes marked "M", and their masses are indicated.