Metabolism of Naphthalene by the Cyanobacterium Oscillatoria sp., Strain JCM

Abstract

Oscillatoria sp., strain JCM grown photoautotrophically in the presence of naphthalene oxidized the aromatic hydrocarbon to cis-1,2-dihydroxy-1,2-dihydronaphthalene, 4-hydroxy-1-tetralone and 1-naphthol. The major metabolite was 1-naphthol. Each product was isolated and shown to have ultraviolet and mass spectra identical to those of authentic compounds. In addition, each metabolite had properties identical to those of authentic compounds when analysed by thin-layer, high-pressure liquid and gas-liquid chromatography. Experiments with [14C]naphthalene showed that, over a 24 h period, the organism oxidized 4·8 % of the added naphthalene. The ratio of organic-soluble to water-soluble metabolites was 41:59. Incubation of whole organisms with naphthalene and 18O2 led to the isolation of 1-naphthol that contained 18O. The organism oxidized 1-[14C]naphthol to 4-hydroxy-1-tetralone. The mechanism of naphthalene oxidation by this cyanobacterium is discussed.