Differential regulation and xenobiotic induction of tandem P450 monooxygenase genes pc-1 (CYP63A1) and pc-2 (CYP63A2) in the white-rot fungus Phanerochaete chrysosporium.
The two tandem P450 monooxygenase genes (pc-1 and pc-2) reported by us earlier in Phanerochaete chrysosporium were investigated for their regulation under nutrient-limited and nutrient-rich culture conditions. Transcript analysis based on real-time quantitative RT-PCR showed higher expression of pc-1 in defined low-nitrogen and pc-2 in defined high-nitrogen media, with maximum expression on day 4, indicating that the two genes, though tandemly linked, are regulated in a non-coordinate manner. Transcript levels of pc-1 and pc-2 were differentially influenced by the type of carbon source, incubation temperature, and oxygenation. Both genes were inducible by organic xenobiotic chemicals. Of the 42 xenobiotics tested in nutrient-rich cultures, pc-1 transcription was induced 2.12(+/-0.40)-fold to 6.27(+/-0.48)-fold in the presence of 19 compounds and pc-2 transcription was induced 2.00(+/-0.73)-fold to 29.39(+/-9.40)-fold in the presence of 22 compounds. Particularly, it is significant that both pc-1 and pc-2 are induced by polycyclic aromatic hydrocarbons (PAHs) of varying ring size, including naphthalene (4.35+/-0.09, 6.02+/-1.39), phenanthrene (2.82+/-0.12, 2.14+/-0.61), pyrene (3.93+/-0.01, 1.0+/-0.12), benzanthracene (1.67+/-0.03, 6.08+/-1.50), and benzo(a)pyrene (1.55+/-0.01, 5.54+/-2.75) respectively. This study constitutes the first report on the identification of P450 genes in a fungus that are responsive to environmentally significant pollutant chemicals (PAHs, DDT, long-chain alkyl phenols) and lignin derivatives.
Doddapaneni
Harshavardhan
H
Molecular Toxicology Division, Department of Environmental Health, University of Cincinnati, College of Medicine, OH 45267-0056, USA.
Yadav
Jagjit S
JS
D000222:Adaptation, Physiological; D001551:Benz(a)Anthracenes / Q000494:pharmacology; D001564:Benzo(a)pyrene / Q000494:pharmacology; D050260:Carbohydrate Metabolism; D003470:Culture Media / Q000737:chemistry; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis* / Q000235:genetics*; D020536:Enzyme Activators / Q000494:pharmacology; D005656:Fungal Proteins / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D009281:Naphthalenes / Q000494:pharmacology; D010100:Oxygen / Q000378:metabolism; D020075:Phanerochaete / Q000201:enzymology* / Q000235:genetics*; D010616:Phenanthrenes / Q000494:pharmacology; D011084:Polycyclic Aromatic Hydrocarbons / Q000494:pharmacology; D011721:Pyrenes / Q000494:pharmacology; D012331:RNA, Fungal / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D013696:Temperature; D014158:Transcription, Genetic; D015262:Xenobiotics / Q000494:pharmacology
D001551:Benz(a)Anthracenes; D003470:Culture Media; D020536:Enzyme Activators; D005656:Fungal Proteins; D009281:Naphthalenes; D010616:Phenanthrenes; D011084:Polycyclic Aromatic Hydrocarbons; D011721:Pyrenes; D012331:RNA, Fungal; D012333:RNA, Messenger; D015262:Xenobiotics; C031721:naphthalene; D001564:Benzo(a)pyrene; C031181:phenanthrene; D003577:Cytochrome P-450 Enzyme System; C030984:pyrene; C030935:benz(a)anthracene; D010100:Oxygen