Cytochrome P450 monooxygenases species differences

Microsomal preparations of Dahlia variabilis flowers have been reported to catalyze the 3-hydroxylation of the 6 -deoxychalcone, isoliquiritigenin, to butein.46 This enzyme activity was shown to be a typical cytochrome P450 monooxygenase that appears to be different from the F3 H, although its occurrence in other species remains to be investigated. 

If the activity of the P450 system varies among animal species, we would expect this to be reflected in the degree of activation of a phosphorothioate insecticide such as parathion. As shown in Figure 9.2, this appears to be the case (Whitehouse and Ecobichon, 1975). The approximately 20-fold difference in paraoxon production by the tissue homogenates probably reflects a combination of cytochrome P450 monooxygenase and esterase activities. 

Table 9.1 Hepatic cytochrome P450 monooxygenase activity in different animal species...

Henczova M, Deer AK, Filla A, Komlosi V, Mink J (2008) Effects of Cu2-t and Pb2-t on different fish species liver cytochrome P450-dependent monooxygenase activities and FTIR spectra. Comp Biochem Physiol C Toxicol Pharmacol 148 53-60... 

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