title: New pathway for the biodegradation of indole in Aspergillus niger.
abstract: Indole and its derivatives form a class of toxic recalcitrant environmental pollutants. The growth of Aspergillus niger was inhibited by very low concentrations (0.005 to 0.02%) of indole, even when 125- to 500-fold excess glucose was present in the medium. When 0.02% indole was added, the fungus showed a lag phase for about 30 h and the uptake of glucose was inhibited. Indole was metabolized by a new pathway via indoxyl (3-hydroxyindole), N-formylanthranilic acid, anthranilic acid, 2,3-dihydroxybenzoic acid, and catechol, which was further degraded by ortho cleavage. The enzymes N-formylanthranilate deformylase, anthranilate hydroxylase, 2,3-dihydroxybenzoate decarboxylase, and catechol dioxygenase were induced by indole as early as after 5 h of growth, and their activities were demonstrated in a cell-free system.
authors.affiliation: Department of Biochemistry, Indian Institute of Science, Bangalore, India.
authors.forename: A V
authors.initials: AV
authors.lastname: Kamath
authors.forename: C S
authors.initials: CS
authors.lastname: Vaidyanathan
mesh_terms: D000581:Amidohydrolases / Q000096:biosynthesis; D001234:Aspergillus niger / Q000201:enzymology / Q000254:growth & development / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002262:Carboxy-Lyases / Q000096:biosynthesis; D050548:Catechol 1,2-Dioxygenase; D049308:Dioxygenases; D004790:Enzyme Induction; D005947:Glucose / Q000378:metabolism; D007211:Indoles / Q000378:metabolism* / Q000494:pharmacology; D006899:Mixed Function Oxygenases / Q000096:biosynthesis; D010105:Oxygenases / Q000096:biosynthesis
chemical_list: D007211:Indoles; C030374:indole; D006899:Mixed Function Oxygenases; D010105:Oxygenases; D049308:Dioxygenases; D050548:Catechol 1,2-Dioxygenase; C023440:anthranilate 2,3-dioxygenase(deaminating); D000581:Amidohydrolases; C063137:N-formylanthranilate deformylase; D002262:Carboxy-Lyases; C022501:2-pyrocatechuate decarboxylase; D005947:Glucose