Anoxygenic degradation of aromatic substances by Rhodopseudomonas palustris.

Three strains of the phototrophic purple nonsulfur bacterium Rhodopseudomonas palustris were isolated from different environments and were evaluated for their aromatic degradative potential under phototrophic conditions. All three strains (PFR1, PNR4, and MRL1) utilized benzoate, 4-hydroxybenzoate, 4-aminobenzoate, 4-aminophenol, cinnamate, ferulate, phloroglucinol, and 4-dimethylaminobenzaldehyde in the absence of exogenous CO2. 4-Aminobenzoate and 4-aminophenol served as a carbon and nitrogen source for all the three strains. Utilization of 4-aminophenol was enhanced in the presence of 4-hydroxybenzoate. Salicylate was utilized by PFR1 and MRL1 strains, and phenol was utilized by the MRL1 strain only in the presence of exogenous CO2.