title: The distinction of different types of cytochromes P-450 from the yeasts Candida tropicalis and Saccharomyces uvarum.
abstract: The distinction between two types of cytochromes P-450 originating from microsomes of Candida tropicalis grown on glucose and on alkane was achieved. Criteria of differentiation between these two cytochrome P-450 forms were based on the characteristics of reduced carbon monoxide difference spectra, on substrate specificity, and on binding and inhibition kinetics of the fungistatic compound propiconazole. One cytochrome P-450 form catalyzed the 14 alpha-demethylation of lanosterol and bound propiconazole with an equimolar ratio. This form was present in microsomes from glucose-grown cells and shared similar characteristics with the cytochrome P-450 originating from Saccharomyces uvarum grown on the same carbon source. The other cytochrome P-450 form catalyzed the terminal hydroxylation of aliphatic hydrocarbons and showed a less specific binding ratio with propiconazole (10(3) mol propiconazole for 1 mol cytochrome P-450). This type of cytochrome P-450 was only present in the microsomes of C. tropicalis grown on alkane.
mesh_terms: D002175:Candida / Q000201:enzymology*; D002248:Carbon Monoxide; D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D007700:Kinetics; D006899:Mixed Function Oxygenases / Q000378:metabolism; D012440:Saccharomyces / Q000201:enzymology*; D013057:Spectrum Analysis; D013379:Substrate Specificity; D014230:Triazoles / Q000494:pharmacology
chemical_list: D065607:Cytochrome P-450 Enzyme Inhibitors; D014230:Triazoles; C045950:propiconazole; D002248:Carbon Monoxide; D003577:Cytochrome P-450 Enzyme System; D006899:Mixed Function Oxygenases