ANAEROBIC DEGRADATION AND TRANSFORMATION OF P-TOLUIDINE BY THE SULFATE-REDUCING BACTERIUM DESULFOBACULA-TOLUOLICA

The ability of the strictly anaerobic sulfate-reducing bacterium Desul fobacula toluolica (strain Tol2) to cometabolically degrade p-toluidin e (p-methylaniline) while using toluene as the primary source of carbo n and energy has been studied. This organism has been shown to modify and degrade toluidine in dense cell suspensions when no other source o f carbon and energy is added. The metabolism led to the formation of a variety of metabolites. From these metabolites a biphenyl-like compou nd as well as phenylacetic acid have been identified by means of HPLC/ MS techniques. The probable conversion of p-toluidine to p-aminophenyl acetic acid and phenylacetic acid as dead end products suggested that this organism initiates p-toluidine degradation by the carboxylation o f the methyl group. If this could be validated in further experiments, it would be the first time that a toluidine was carboxylated at the m ethyl moiety by an anaerobic, sulfate-reducing bacterium.