Figure 5. Conformational change and thioester reactions of TEP1*S1 and TEP1*R1 in vitro.

TEP1 N- and C-terminal fragments are shown as horizontal ovals linked by the protease-sensitive region, the thioester bond is indicated by a star. Full-length TEP1 is secreted in a pro-form. Limited proteolysis in the hemolymph to a meta form is followed by a slow conversion to an active form. The LRIM1/APL1C pathway involves capture and stabilization of the mature form of TEP1*S1. Methylamine (MeNH₂) was previously used to produce a ternary complex of reacted TEP1*R1_cut with LRIM1/APL1C [15].