N-dealkylation of atrazine by hydrogenotrophic fluorescent pseudomonads

Strains LMG 10141 and 10140 of Pseudomonas fluorescens were cultured in a hydrogen-oxygen atmosphere in a nutrient solution containing 30 mg atrazine per litre. Atrazine was monitored by gas chromatography and its degradation products deisopropylatrazine and deethylatrazine by high performance liquid chromatography. Atrazine was degraded to the latter compounds but only in the presence of hydrogen. Hydroxyatrazine was not detected in cultures of LMG 10141. Experiments with carbon-14 labelled atrazine suggested that neither the alkyl chains nor the ring structure were completely mineralized.