Methyl tert-butyl ether (MTBE) was widely used as a gasoline additive, replacing lead as an antiknocking agent. Tert-butyl alcohol (TBA), a breakdown product of MTBE, and a gasoline additive in its own right, is also used as a solvent. MTBE and TBA are toxic and potentially carcinogenic compounds, that are also extremely mobile in groundwater, often creating large groundwater plumes. For these reasons, both compounds are regulated contaminants in several US States. Fortunately, biodegradation of MTBE/TBA is commonly reported via aerobic pathways; although these compounds are often more recalcitrant than the fuel which introduced them to groundwater.
As part of a growing suite of Gene-Trac® tests, SiREM now offers targets for the biodegradation of MTBE and TBA that focus on a key MTBE degrading microorganism and functional genes. Methylibium petroleiphilum PM1 was isolated from a culture enriched with MTBE from a biofilter. M. petroleiphilum PM1 is widely found in MTBE contaminated groundwater and is considered a major organism involved in degradation of MTBE and TBA1,2.