A unique enzyme catalyzing the formation of 4-hydroxyaniline from 4-amino-benzoic acid in Agaricus bisporus

A unique enzyme that catalyzes the formation of 4-hydroxyaniline from 4-aminobenzoic acid was found in the homogenate of Agaricus bisporus. The enzyme was prepared from the homogenate by (NH4)2SO4 fractionation, gel filtration and ion-exchange chromatography. The products formed from 4-aminobenzoic acid by the enzyme were shown to be 4-hydroxyaniline and CO2. The reaction required FAD, NAD(P)H and O2. These results indicate that the enzyme is a new FAD-dependent monooxygenase.