Spectral and catalytic properties of cytochrome P-450 from four wild bird species

1. The n-octylamine difference spectra in all bird species were analogous to the high-spin form of cytochrome P-450 obtained in mammalian species after induction with 3-methylcholanthrene. 2. Differences between species were obtained in the ratios of the 430/455 nm peaks in the Soret region for the ethyl isocyanide difference spectra. 3. An atypical type I spectral change with methylaniline as ligand was found in one species and the reverse form of this spectral change was obtained in three other species. 4. Significant differences between species were also found in the K s values for aniline and ethyl isocyanide spectral changes and in catalytic activity with different substrates.