A bacterial strain, PM1, which is able to utilize methyltert-butyl ether (MTBE) as its sole carbon and energy source, was isolated from a mixed microbial consortium in a compost biofilter capable of degrading MTBE. Initial linear rates of MTBE degradation by 2 × 106 cells ml?1 were 0.07, 1.17, and 3.56 μg ml?1 h?1 for initial concentrations of 5, 50, and 500 μg MTBE ml?1, respectively. When incubated with 20 μg of uniformly labeled [14C]MTBE ml?1, strain PM1 converted 46% to14CO2 and 19% to 14C-labeled cells within 120 h. This yield is consistent with the measurement of protein accumulation at different MTBE concentrations from which was estimated a biomass yield of 0.18 mg of cells mg MTBE?1. Strain PM1 was inoculated into sediment core material collected from a contaminated groundwater plume at Port Hueneme, California, in which there was no evidence of MTBE degradation. Strain PM1 readily degraded 20 μg of MTBE ml?1 added to the core material. The rate of MTBE removal increased with additional inputs of 20 μg of MTBE ml?1. These results suggest that PM1 has potential for use in the remediation of MTBE-contaminated environments.
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