Abstract
We have isolated a mixed bacterial culture (BC-1) which is capable of degrading the gasoline oxygenate methyl t-butyl ether (MTBE). BC-1 was developed from seed microorganisms present in a chemical plant biotreater sludge. This enrichment culture has been maintained in continuous culture treating high concentrations of MTBE (120 to 200 mg/liter) as the sole carbon source in a simple feed containing NH4+, PO43-, Mg2+, and Ca2+ nutrients. The unit had a stable MTBE removal rate when maintained with a long cell retention time (ca. 80 to 90 days); however, when operated at a ≤50-day cell waste rate, loss of MTBE-degrading activity was observed. The following three noteworthy experimental data show that MTBE is biodegraded extensively by BC-1: (i) the continuous (oxygen-sparged) culture was able to sustain a population of autotrophic ammonia-oxidizing bacteria which could nitrify influent NH4+ concentrations at high rates and obtain CO2 (sole carbon source for growth) from the metabolism of the alkyl ether, (ii) BC-1 metabolized radiolabeled either (14CH3O-MTBE) to 14CO2 (40%) and 14C-labeled cells (40%), and (iii) cell suspensions of the culture were capable of degrading (substrate depletion experiments) MTBE to t-butyl alcohol, a primary metabolite of MTBE. BC-1 is a mixed culture containing several bacterial species and is the first culture of its kind which can completely degrade an alkyl ether.
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Selected References
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- Liaw H. J., Srinivasan V. R. Molecular cloning and expression of an Erwinia sp. gene encoding diphenyl ether cleavage in Escherichia coli. Appl Environ Microbiol. 1989 Sep;55(9):2220–2225. doi: 10.1128/aem.55.9.2220-2225.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Meyers A. J., Jr Obligate methylotrophy: evaluation of dimethyl ether as a C1 compound. J Bacteriol. 1982 May;150(2):966–968. doi: 10.1128/jb.150.2.966-968.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Oremland R. S., Culbertson C. W. Evaluation of methyl fluoride and dimethyl ether as inhibitors of aerobic methane oxidation. Appl Environ Microbiol. 1992 Sep;58(9):2983–2992. doi: 10.1128/aem.58.9.2983-2992.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sturm R. N. Biodegradability of nonionic surfactants: screening test for predicting rate and ultimate biodergradation. J Am Oil Chem Soc. 1973 May;50(5):158–167. doi: 10.1007/BF02640470. [DOI] [PubMed] [Google Scholar]
- Tonge G. M., Harrison D. E., Higgins I. J. Purification and properties of the methane mono-oxygenase enzyme system from Methylosinus trichosporium OB3b. Biochem J. 1977 Feb 1;161(2):333–344. doi: 10.1042/bj1610333. [DOI] [PMC free article] [PubMed] [Google Scholar]
- van den Wijngaard A. J., Prins J., Smal A. J., Janssen D. B. Degradation of 2-Chloroethylvinylether by Ancylobacter aquaticus AD25 and AD27. Appl Environ Microbiol. 1993 Sep;59(9):2777–2783. doi: 10.1128/aem.59.9.2777-2783.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]