title: Spectral similarities between "H-450" and cytochrome P-450.
abstract: The absorption spectrum of reduced H-450 was reversibly affected by a pH change; the Soret peak of the alkaline form was at 448 nm, and that of the acidic form (H-420) at 425 nm. The same spectral change of conversion of reduced H-450 to H-420 was also produced by the action of n-butanol, urea and p-chloromercuribenzoate. These spectral properties of H-450 were similar to those of the conversion of cytochrome P-450 to cytochrome P-420, suggesting the similar heme environments of these two hemoproteins. Reduced H-450 bound carbon monoxide to be transformed into a new spectral species having a Soret peak at 420 nm.
mesh_terms: D020001:1-Butanol; D000818:Animals; D000440:Butanols; D002248:Carbon Monoxide; D055598:Chemical Phenomena; D002621:Chemistry; D002729:Chloromercuribenzoates; D003577:Cytochrome P-450 Enzyme System / Q000032:analysis*; D003600:Cytosol / Q000201:enzymology; D006420:Hemeproteins / Q000032:analysis*; D006863:Hydrogen-Ion Concentration; D008099:Liver / Q000201:enzymology; D008297:Male; D010084:Oxidation-Reduction; D051381:Rats; D011919:Rats, Inbred Strains; D013053:Spectrophotometry; D014508:Urea; D020245:p-Chloromercuribenzoic Acid
chemical_list: D000440:Butanols; D002729:Chloromercuribenzoates; C043311:H 450; D006420:Hemeproteins; D020245:p-Chloromercuribenzoic Acid; D002248:Carbon Monoxide; D020001:1-Butanol; D014508:Urea; D003577:Cytochrome P-450 Enzyme System