Response of termite (Reticulitermes flavipes) cytochrome P450 enzymes when subjected to oxidation inhibitors
Mary Kubiszak-Rushton, Michael E. Scharf
Subterranean termites feed almost exclusively on wood lignocellulose which contains xenobiotics. Cytochrome P450 enzymes are one of the key mechanisms that termites use to metabolize these xenobiotics and minimize potential toxicity. Compounds that contain a methylene dioxyphenyl group have been shown to inhibit the oxidation of xenobiotics by P450 enzymes. Two similar compounds that contain this group are piperonyl butoxide (PBO) and sesame oil. Our lab has previously shown that more P450 enzymes were up-regulated in R. flavipes with the consumption of wood than paper. Here we hypothesized that applying sesame oil and PBO to food substrates would result in higher mortality of R. flavipes workers when fed on wood compared to paper. The idea behind this hypothesis is that, if in fact sesame oil and PBO inhibit the right P450 enzymes, then the termites could become more susceptible to the toxins in wood. We investigated these potential treatment effects by evaluating mortality, substrate consumption, and termite weight reduction. This study is the first phase of a larger project to characterize termite P450 enzymes involved in xenobiotic metabolism in R. flavipes.
