Oligomerization of 4-Chloroaniline by Oxidoreductases

• Published in: Environmental science & technology Vol. 21; no. 10; pp. 999 - 1003
• Main Authors: Simmons, Kathleen E, Minard, Robert D, Bollag, Jean-Marc
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01-10-1987
• Subjects: Analytical, structural and metabolic biochemistry; Biological and medical sciences; Enzymes and enzyme inhibitors; Fundamental and applied biological sciences. Psychology; Oxidoreductases; Trametes versicolor; HPLC chromatography; Oligomerization; Enzyme; Oxidoreductase
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es50001a014

Oxidation of aromatic amines by oxidoreductases can result in the formation of polyaromatic products. We incubated 4-chloroaniline with horseradish peroxidase and with a laccase from the fungus Trametes versicolor . Qualitative and quantitative analyses were performed on the oligomeric products. Both enzymes generated eight oligomers, which were isolated and identified. On the basis of their structures and rates of formation, a reaction scheme for the oxidative oligomerization of 4-chloroaniline was proposed. The scheme shows that, once the substrate was enzymatically oxidized, free-radical coupling followed, and three dimeric intermediates were produced. Each of the dimers initiated a nonenzymatic reaction pathway, and the combined pathways accounted for the formation of the first eight stable 4-chloroaniline-derived oligomers.