MICROBIAL-METABOLISM OF AROMATIC-AMINES .13. INDUCTION, PURIFICATION, AND CHARACTERIZATION OF CATECHOL 2,3-DIOXYGENASE FROM ANILINE-ASSIMILATING PSEUDOMONAS SP FK-8-2

Catechol 2,3-dioxygenase (EC 1.13, 1.2) was induced by aniline in cells of the aniline-assimilating Pseudomonas sp. FK-8-2 isolated from soil. The addition of polypepton besides aniline to the incubation mixture promoted the induction of this enzyme. The enzyme was purified to homogeneity with the high recovery of 95% from a cell-free extract of anilin-grown Pseudomonas sp. FK-8-2. The purified enzyme was stable between pH 6.0 and 7.0 and up to 70-degrees-C in the presence of 5% (v/v) acetone, which protected this enzyme from inactivation by air and other oxidizing agents. The molecular weight of the enzyme was 120,000 by gel filtration. It was dissociated into four identical subunits with molecular weight of 33,000 on a sodium dodecyl sulfate-polyacrylamide gel. This enzyme catalyzed the extradiol cleavage of 3- and 4-chlorocatechol, 3- and 4-methylcatechol, and 3-fluorocatechol.