SDS-PAGE analysis of purified proteins. Proteins (3 μg/lane) were subjected to SDS-PAGE under reducing conditions and visualized by staining with Coomassie Brilliant Blue R-250. Lane 1 represents pt-rFV; lane 2, pt-rFV-QQ; lane 3, pt-rFV plus thrombin; lane 4, pt-rFV-QQ plus thrombin; lane 5, rFX; lane 6, rFXa; and lane 7, pt-FXa. The apparent molecular weights of the standards are indicated on the left. N-terminal sequence results of the indicated protein bands are shown. The dash (–) following the Val (panel B) indicates that the yield was too low to accurately assign an amino acid and likely represents the presence of γ-carboxyglutamic acid.