MINERALIZATION OF MONOFLUOROBENZOATE BY A DICULTURE UNDER SULFATE-REDUCING CONDITIONS

A mesophilic, dehalogenating, sulfate-reducing diculture was isolated from an anaerobic lake sediment. One strain of the diculture is propos ed to be an endospore-forming Desulfolomaculum species, the second str ain was a vibrioid, motile and non-sporeforming species which is tenta tively assigned to the genus Desulfovibrio. The diculture was able to mineralize 4- and 2-fluorobenzoate both isomers being incompletely oxi dized with the release of acetate, which was subsequently used by both sulfate-reducing strains. Other electron donors used for growth inclu ded benzoate, 3- and 4-hydroxybenzoate, protocatechuate, catechol, phe nol, 2,5-dimethoxyphenol, fatty acids up to C-8, malate and pyruvate. The culture obtained from a freshwater habitat grew optimally at NaCl concentrations of 0.3-0.5 g l(-1), 33-37 degrees C, and pH 7.4. Our ex periments showed that certain fluorinated aromatic hydrocarbons could serve as sole sources of carbon and energy for sulfate-reducing bacter ia.