Diversification of furanocoumarin-metabolizing cytochrome P450 monooxygenases in two papilionids: Specificity and substrate encounter rate.

ABSTRACT: Diversification of cytochrome P450 monooxygenases (P450s) is thought to result from antagonistic interactions between plants and their herbivorous enemies. However, little direct evidence demonstrates the relationship between selection by plant toxins and adaptive changes in herbivore P450s. Here we show that the furanocoumarin-metabolic activity of CYP6B proteins in two species of swallowtail caterpillars is associated with the probability of encountering host plant furanocoumarins. Catalytic activity was compared in two closely related CYP6B4 and CYP6B17 groups in the polyphagous congeners Papilio glaucus and Papilio canadensis. Generally, P450s from P. glaucus, which feeds occasionally on furanocoumarin-containing host plants, display higher activities against furanocoumarins than those

SUBMITTER: Li W 

PROVIDER: S-EPMC304124 | biostudies-literature | 2003 Nov

REPOSITORIES: biostudies-literature