Purity > 85% as determined by SDS-PAGE. MW: 33.8kDa. Partial: 763-1019aa. N-terminal 10xHis-tagged and C-terminal Myc-tagged. Tachypleus tridentatus (Japanese horseshoe crab). This enzyme is closely associated with an endotoxin-sensitive hemolymph coagulation system which may play important roles in both hemostasis and host defense mechanisms. Its active form catalyzes the activation of factor B.