title: Nitrate induces enzymes of the mannitol cycle and suppresses versicolorin synthesis in Aspergillus parasiticus.
abstract: Addition of sodium nitrate to growing cultures of Aspergillus parasiticus (ATCC 36537) induces the synthesis of enzymes involved in nitrate assimilation (NO3- reductase), of enzymes in the pentose pathway (glucose-6-phosphate dehydrogenase), and of enzymes in the mannitol cycle (mannitol- and mannitol-1-phosphate dehydrogenases). Addition of NO3- also causes a dose-dependent suppression of synthesis of the polyketide secondary metabolite, versicolorin A. We suggest that in the presence of NO3- plus peptone, the cytoplasmic NADPH/NADP ratio may be elevated, resulting in increased conversion of malonyl coenzyme A to fatty acid rather than to polyketide.
authors.affiliation: Biochemistry and Nutrition, Virginia Polytechnic Institute and State University, Blacksburg 24061.
authors.forename: W G
authors.initials: WG
authors.lastname: Niehaus
authors.forename: W P
authors.initials: WP
authors.lastname: Jiang
mesh_terms: D000880:Anthraquinones / Q000378:metabolism*; D001230:Aspergillus / Q000187:drug effects / Q000201:enzymology*; D008354:Mannitol Dehydrogenases / Q000378:metabolism*; D050901:Nitrate Reductase; D009565:Nitrate Reductases / Q000378:metabolism*; D009566:Nitrates / Q000494:pharmacology*; D010427:Pentose Phosphate Pathway
chemical_list: D000880:Anthraquinones; D009566:Nitrates; C005888:versicolorins; D008354:Mannitol Dehydrogenases; D009565:Nitrate Reductases; D050901:Nitrate Reductase