Expression of Manduca sexta serine proteinase homolog precursors in insect cells and their proteolytic activation.


Phenoloxidase (PO)-catalyzed reactions are crucial to the survival of insects after a pathogen or parasite infection. In Manduca sexta, active PO is generated from its precursor by a prophenoloxidase activating proteinase (PAP) in the presence of non-catalytic serine proteinase homologs (SPHs). The PAP and SPHs, located at the ends of a branched proteinase… (More)