Styrene metabolism in Exophiala jeanselmei and involvement of a cytochrome P-450-dependent styrene monooxygenase.
The yeast-like fungus Exophiala jeanselmei degrades styrene via initial oxidation of the vinyl side chain to phenylacetic acid, which is subsequently hydroxylated to homogentisic acid. The initial reactions are catalyzed by a NADPH- and flavin adenine dinucleotide-dependent styrene monooxygenase, a styrene oxide isomerase, and a NAD(+)-dependent phenylacetaldehyde dehydrogenase. The reduced CO-difference spectrum of microsomal preparations of styrene-grown cells shows a characteristic absorption maximum at 450 nm, which strongly suggests the involvement of a cytochrome P-450-dependent styrene monooxygenase. Inhibition of styrene monooxygenase activity in cell extracts by cytochrome P-450 inhibitors SKF-525-A, metyrapone, and CO confirms this assumption.
Cox
H H
HH
Department of Environmental Biotechnology, TNO Institute of Environmental Sciences, Energy Research and Process Innovation, JA Delft, Netherlands.
Faber
B W
BW
Van Heiningen
W N
WN
Radhoe
H
H
Doddema
H J
HJ
Harder
W
W
D000393:Air Pollutants / Q000378:metabolism; D001673:Biodegradation, Environmental; D002248:Carbon Monoxide / Q000494:pharmacology; D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005093:Exophiala / Q000378:metabolism*; D008797:Metyrapone / Q000494:pharmacology; D010105:Oxygenases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011335:Proadifen / Q000494:pharmacology; D013053:Spectrophotometry; D020058:Styrene; D013343:Styrenes / Q000737:chemistry / Q000378:metabolism*
D000393:Air Pollutants; D065607:Cytochrome P-450 Enzyme Inhibitors; D004791:Enzyme Inhibitors; D013343:Styrenes; D020058:Styrene; D002248:Carbon Monoxide; D003577:Cytochrome P-450 Enzyme System; D011335:Proadifen; D010105:Oxygenases; C026721:styrene monooxygenase; D008797:Metyrapone