Oxidation of polycyclic aromatic heterocycles by Pseudomonas fluorescens TTC1

The mutant strain Pseudomonas fluorescens TTC1 (NCIMB 40605), derived from the naphthalene-degrading P. fluorescens N3 (NCIMB 40530), was used for the biotransformation of polycyclic aromatic heterocycles such as dibenzothiophene, dibenzofuran, thianthrene xanthen and acridine. The cis-1,2- and cis-3,4-dihydrodiols produced were isolated and identified from the culture filtrate. Both the regioselectivity and the productivity of the transformations, catalysed by the naphthalene dioxygenase enzymatic system, were dramatically influenced by the presence of the heteroatom. The high substrate tolerance displayed by the enzyme might be useful in the biotransformation of other related compounds.