Partial amino acid sequences of a soluble protoporphyrinogen-oxidizing enzyme (PPO) purified from tobacco cultured cells were identified. The sequences of two regions of the soluble PPO corresponded to the acid/base catalysis and heme binding regions of plant peroxidases. Anti-soluble PPO IgG cross-reacted with these plant peroxidases. Thus, the soluble PPO seems to be a kind of peroxidase.
We have tested the effects of chemicals on bombykol production in vitro in the silkworm, Bombyx mori, to probe the biochemical steps as well as underlying mechanisms regulated by PBAN. These results suggest the involvement of calmodulin and phosphoprotein phosphatase in the intracellular signal transduction of PBAN action.