Additional file 1: of The structure of a prophenoloxidase (PPO) from Anopheles gambiae provides new insights into the mechanism of PPO activation

AgPPO8 exists as a homodimer in solution. (A) AgPPO8 appears as dimeric on size exclusion chromatography (SEC). The theoretical molecular weight (MW) of AgPPO8 monomer is 81 kDa, calculated by ExPASy server ( http://web.expasy.org/compute_pi/ ). The retention volumes are aligned between the standard proteins (Upper panel) and AgPPO8 (Lower panel). Standards: thyroglobulin (bovine), 670 kDa; γ-globulin (bovine), 158 kDa; ovalbumin (chicken), 44 kDa; myoglobin (horse), 17 kDa; vitamin B12, 1.35 kDa. AgPPO8 was eluted out at a similar retention volume as that of γ-globulin (bovine). The calculated MW of AgPPO8 from the chromatograph is 142 kDa, indicating a dimer. (B) AgPPO8 displays as dimeric from dynamic light scattering. AgPPO8 at a concentration of 1.5 mg/mL was used in the experiment. AgPPO8 displays as monodisperse in solution with a MW of 165.9 ± 30.5 kDa, corresponding to a dimer and consistent with the result from SEC analysis. (TIF 1376 kb