Ghosh D K, Dutta D, Samanta T B, Mishra A K
Biochem Biophys Res Commun. 1983 Jun 15;113(2):497-505. doi: 10.1016/0006-291x(83)91753-9.
Microsomal preparations of Aspergillus ochraceus TS oxidised benzo(a)pyrene very efficiently in the presence of NADPH and 02 and exhibits a pH optimum of 8.0-8.2. The hydroxylation is also effected in presence of NaI04. Hydroxylation was inhibited by metyrapone, SKF-525A, PCMB, imidazole, carbon monoxide and flavone but not by cyanide, azide and antimycin A indicating thereby the involvement of cytochrome P-450 in this reaction. Inhibition by cytochrome C is consistent with the participation of NADPH-cytochrome C reductase in this hydroxylation. Reduced microsomes and its solubilized preparation, when treated with carbon monoxide, showed absorption maxima at 453 and 449 respectively. Different classical inducers of cytochrome P-450 induce the benzo(a)-pyrene hydroxylase activity to varying degree and as such suggests the existence of multiple forms of cytochrome P-450 in this fungus.
