title: Partial characterization of hepatic micorsomes from tupaia glis.
abstract: The dithionite difference spectrum of Tupaia microsomal cytochrome P-450-CO complex has an absorbance maximum at 449 nm, rather than at 450 nm as found for rat, rabbit, mouse, guinea pig, and human microsomes. N-octylamine difference spectroscopy showed the ratio of high- and low-spin forms of cytochrome P-450 to be different from that of the rat, indicating that the 449 nm absorption maximum might be due to a high concentration of the high-spin form, cytochrome P-448. The Tupaia microsomes demonstrated greater aryl hydrocarbon activity than microsomes prepared from male rats. These preliminary results suggest that Tupaia microsomes contain a modified terminal oxygenase which is responsible for the observed rapid metabolism of benzo[alpha]pyrene.
mesh_terms: D000818:Animals; D002248:Carbon Monoxide; D003577:Cytochrome P-450 Enzyme System / Q000032:analysis; D004227:Dithionite; D006168:Guinea Pigs; D000882:Haplorhini; D006801:Humans; D006838:Hydrocarbons; D008297:Male; D051379:Mice; D008862:Microsomes, Liver / Q000032:analysis*; D006899:Mixed Function Oxygenases / Q000032:analysis; D011817:Rabbits; D051381:Rats; D013045:Species Specificity; D013056:Spectrophotometry, Ultraviolet; D014418:Tupaiidae
chemical_list: D006838:Hydrocarbons; D004227:Dithionite; D002248:Carbon Monoxide; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases