Microbial metabolism of fluoranthene: isolation and identification of ring fission products

Abstract

The degradation of fluoranthene by pure cultures of Alcaligenes denitrificanss WW1, isolated from contaminated soil samples, was investigated. The strain showed maximum degradation rates of 0.3 mg fluoranthene/ml per day. A denitrificans was able to utilize also naphthalene, 1- and 2-methylnaphthalene, phenanthrene, and anthracene as sole carbon sources and to co-metabolize fuuorence, pyrene, and benzo(a)anthracene. During growth on fluoranthene in batch culture two metabolic products that were completely degraded before growth entered the stationary phase were detected in the culture fluid. Anslyses by UV, mass and NMR spectroscopy identified the products as acenaphthenone and 3-hydroxymethyl-4,5-benzocoumarine. Fluoranthene-grown resting cells of A. denitrificans showed degradative activity towards 2,3-dihydroxybenzoic acid, pyrogallol, salicylic acid, and catechol. The enzymatic activities in extracts of fluoranthene-induced cells indicate a meta ring fission involved in the degradation of fluoranthene. From these data new aspects of the biodegradative pathway of fluoranthene have been predicted.