Assessment of the metabolic capacity and adaptability of aromatic hydrocarbon degrading strain Pseudomonas putida CSV86 in aerobic chemostat culture

Abstract

Pseudomonas putida CSV86 utilizes aromatic compounds preferentially over sugars and co-metabolizes aromatics along with organic acids. In the present study, the metabolic capacity and adaptability of strain CSV86 were assessed in a chemostat at benzyl alcohol concentrations ranging from 1gl−1 to 3gl−1 and in the presence of glucose and succinate by systematically varying the dilution rate. Complete removal of benzyl alcohol was achieved for loadings up to 640mgl−1h−1 in presence of benzyl alcohol alone. The strain responded within 1min towards step changes in substrate loading as indicated by an increase in the oxygen uptake rate, presumably as a result of excess metabolic capacity. These results suggest that CSV86 exhibits considerable metabolic elasticity upon increase in substrate load. Metabolic elasticity of the microorganism is an important parameter in wastewater treatment plants due to the changing substrate loads.