Use of proteomics and physiological characteristics to elucidate ecotoxic effects of methyl tert-butyl ether in Pseudomonas putida KT2440.

We monitored rates of growth, ATP-synthesis, respiration, and death to assess the sensitivity of the model organism Pseudomonas putida KT2440 to methyl tert-butyl ether (MTBE), and its degree of toxicity. The physiological data obtained suggested that the energy conservation system was the most sensitive site. However, with the help of proteomic analysis we obtained further information and deeper insight into the molecular mechanisms involved. This analysis indicated that sensitivity involves oxidative stress since alkylhydroperoxide reductase C (AhpC) and two superoxide dismutases (SodM, SodF) were amplified in the presence of MTBE. Thus, proteomics has major advantages in ecotoxicological investigations where the aims include elucidation of the molecular mechanisms as well as characterization of the ecostress and the potency of the stressor(s).