Biodegradation of Methyl tert-Butyl Ether and Other Fuel Oxygenates by a New Strain, Mycobacterium austroafricanum IFP 2012

ABSTRACT A strain that efficiently degraded methyl tert-butyl ether (MTBE) was obtained by initial selection on the recalcitrant compound tert-butyl alcohol (TBA). This strain, a gram-positive methylotrophic bacterium identified as Mycobacterium austroafricanum IFP 2012, was also able to degrade tert-amyl methyl ether and tert-amyl alcohol. Ethyl tert-butyl ether was weakly degraded. tert-Butyl formate and 2-hydroxy isobutyrate (HIBA), two intermediates in the MTBE catabolism pathway, were detected during growth on MTBE. A positive effect of Co2+ during growth of M. austroafricanum IFP 2012 on HIBA was demonstrated. The specific rate of MTBE degradation was 0.6 mmol/h/g (dry weight) of cells, and the biomass yield on MTBE was 0.44 g (dry weight) per g of MTBE. MTBE, TBA, and HIBA degradation activities were induced by MTBE and TBA, and TBA was a good inducer. Involvement of at least one monooxygenase during degradation of MTBE and TBA was shown by (i) the requirement for oxygen, (ii) the production of propylene epoxide from propylene by MTBE- or TBA- grown cells, and (iii) the inhibition of MTBE or TBA degradation and of propylene epoxide production by acetylene. No cytochrome P-450 was detected in MTBE- or TBA-grown cells. Similar protein profiles were obtained after sodium dodecyl sulfate-polyacrylamide gel electrophoresis of crude extracts from MTBE- and TBA-grown cells. Among the polypeptides induced by these substrates, two polypeptides (66 and 27 kDa) exhibited strong similarities with known oxidoreductases.

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Oxidation of Methyl tert-Butyl Ether by Alkane Hydroxylase in Dicyclopropylketone-Induced and n-Octane-Grown Pseudomonas putida GPo1

Applied and Environmental Microbiology ◽

10.1128/aem.70.8.4544-4550.2004 ◽

2004 ◽

Vol 70 (8) ◽

pp. 4544-4550 ◽

Cited By ~ 43

Author(s):

Christy A. Smith ◽

Michael R. Hyman

Keyword(s):

Pseudomonas Putida ◽

Kinetic Studies ◽

Butyl Alcohol ◽

Amyl Alcohol ◽

Methyl Tert Butyl Ether ◽

Rich Medium ◽

Hydroxylase Activity ◽

Alkane Hydroxylase ◽

Butyl Ether ◽

Putative Mechanism

ABSTRACT The alkane hydroxylase enzyme system in Pseudomonas putida GPo1 has previously been reported to be unreactive toward the gasoline oxygenate methyl tert-butyl ether (MTBE). We have reexamined this finding by using cells of strain GPo1 grown in rich medium containing dicyclopropylketone (DCPK), a potent gratuitous inducer of alkane hydroxylase activity. Cells grown with DCPK oxidized MTBE and generated stoichiometric quantities of tert-butyl alcohol (TBA). Cells grown in the presence of DCPK also oxidized tert-amyl methyl ether but did not appear to oxidize either TBA, ethyl tert-butyl ether, or tert-amyl alcohol. Evidence linking MTBE oxidation to alkane hydroxylase activity was obtained through several approaches. First, no TBA production from MTBE was observed with cells of strain GPo1 grown on rich medium without DCPK. Second, no TBA production from MTBE was observed in DCPK-treated cells of P. putida GPo12, a strain that lacks the alkane-hydroxylase-encoding OCT plasmid. Third, all n-alkanes that support the growth of strain GPo1 inhibited MTBE oxidation by DCPK-treated cells. Fourth, two non-growth-supporting n-alkanes (propane and n-butane) inhibited MTBE oxidation in a saturable, concentration-dependent process. Fifth, 1,7-octadiyne, a putative mechanism-based inactivator of alkane hydroxylase, fully inhibited TBA production from MTBE. Sixth, MTBE-oxidizing activity was also observed in n-octane-grown cells. Kinetic studies with strain GPo1 grown on n-octane or rich medium with DCPK suggest that MTBE-oxidizing activity may have previously gone undetected in n-octane-grown cells because of the unusually high Ks value (20 to 40 mM) for MTBE.

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Roles of tert-butyl formate, tert-butyl alcohol and acetone in the regulation of methyl tert-butyl ether degradation by Mycobacterium austroafricanum IFP�2012

Applied Microbiology and Biotechnology ◽

10.1007/s00253-003-1268-9 ◽

2003 ◽

Vol 62 (2-3) ◽

pp. 256-262 ◽

Cited By ~ 33

Author(s):

A. Fran�ois ◽

L. Garnier ◽

H. Mathis ◽

F. Fayolle ◽

F. Monot

Keyword(s):

Butyl Alcohol ◽

Methyl Tert Butyl Ether ◽

Butyl Ether ◽

Tert Butyl ◽

Tert Butyl Alcohol ◽

Mycobacterium Austroafricanum

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Involvement of a Novel Enzyme, MdpA, in Methyl tert-Butyl Ether Degradation in Methylibium petroleiphilum PM1

Applied and Environmental Microbiology ◽

10.1128/aem.01192-08 ◽

2008 ◽

Vol 74 (21) ◽

pp. 6631-6638 ◽

Cited By ~ 31

Author(s):

Radomir Schmidt ◽

Vince Battaglia ◽

Kate Scow ◽

Staci Kane ◽

Krassimira R. Hristova

Keyword(s):

Molecular Genetic ◽

Genetic System ◽

Butyl Alcohol ◽

Methyl Tert Butyl Ether ◽

Butyl Ether ◽

Environmental Strain ◽

Insertional Inactivation ◽

Mycobacterium Austroafricanum ◽

Fuel Oxygenate ◽

Alkane Hydroxylases

ABSTRACT Methylibium petroleiphilum PM1 is a well-characterized environmental strain capable of complete metabolism of the fuel oxygenate methyl tert-butyl ether (MTBE). Using a molecular genetic system which we established to study MTBE metabolism by PM1, we demonstrated that the enzyme MdpA is involved in MTBE removal, based on insertional inactivation and complementation studies. MdpA is constitutively expressed at low levels but is strongly induced by MTBE. MdpA is also involved in the regulation of tert-butyl alcohol (TBA) removal under certain conditions but is not directly responsible for TBA degradation. Phylogenetic comparison of MdpA to related enzymes indicates close homology to the short-chain hydrolyzing alkane hydroxylases (AH1), a group that appears to be a distinct subfamily of the AHs. The unique, substrate-size-determining residue Thr59 distinguishes MdpA from the AH1 subfamily as well as from AlkB enzymes linked to MTBE degradation in Mycobacterium austroafricanum.

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Combined toxicities of methyl tert-butyl ether and its metabolite tert-butyl alcohol on earthworms via different exposure routes

Chemosphere ◽

10.1016/j.chemosphere.2015.01.023 ◽

2015 ◽

Vol 128 ◽

pp. 191-198 ◽

Cited By ~ 9

Author(s):

Woo-Mi Lee ◽

Youngdae Yoon ◽

Youn-Joo An

Keyword(s):

Butyl Alcohol ◽

Methyl Tert Butyl Ether ◽

Butyl Ether ◽

Tert Butyl ◽

Tert Butyl Alcohol ◽

Exposure Routes

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Comparison of the Structural Characteristics of Native Collagen Fibrils Derived from Bovine Tendons Using Two Different Methods: Modified Acid-Solubilized and Pepsin-Aided Extraction

Materials ◽

10.3390/ma13020358 ◽

2020 ◽

Vol 13 (2) ◽

pp. 358 ◽

Cited By ~ 2

Author(s):

Haiyan Ju ◽

Xiuying Liu ◽

Gang Zhang ◽

Dezheng Liu ◽

Yongsheng Yang

Keyword(s):

Type I Collagen ◽

Structural Characteristics ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Dry Weight ◽

Collagen Fibrils ◽

Type I ◽

X Ray Diffraction ◽

Aggregation Structure ◽

Native Collagen

Native collagen fibrils (CF) were successfully extracted from bovine tendons using two different methods: modified acid-solubilized extraction for A-CF and pepsin-aided method for P-CF. The yields of A-CF and P-CF were up to 64.91% (±1.07% SD) and 56.78% (±1.22% SD) (dry weight basis), respectively. The analyses of both amino acid composition and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) confirmed that A-CF and P-CF were type I collagen fibrils. Both A-CF and P-CF retained the intact crystallinity and integrity of type I collagen’s natural structure by FTIR spectra, circular dichroism spectroscopy (CD) and X-ray diffraction detection. The aggregation structures of A-CF and P-CF were displayed by UV–Vis. However, A-CF showed more intact aggregation structure than P-CF. Microstructure and D-periodicities of A-CF and P-CF were observed (SEM and TEM). The diameters of A-CF and P-CF are about 386 and 282 nm, respectively. Although both A-CF and P-CF were theoretically concordant with the Schmitt hypothesis, A-CF was of evener thickness and higher integrity in terms of aggregation structure than P-CF. Modified acid-solubilized method provides a potential non-enzyme alternative to extract native collagen fibrils with uniform thickness and integral aggregation structure.

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Anaerobic biodegradation of methyl tert-butyl ether and tert-butyl alcohol in petrochemical wastewater

Environmental Technology ◽

10.1080/09593330.2012.655313 ◽

2012 ◽

Vol 33 (16) ◽

pp. 1937-1943 ◽

Cited By ~ 4

Author(s):

Mohammad Ghasemian ◽

Mohammad Mehdi Amin ◽

Eberhard Morgenroth ◽

Neemat Jaafarzadeh

Keyword(s):

Anaerobic Biodegradation ◽

Butyl Alcohol ◽

Methyl Tert Butyl Ether ◽

Petrochemical Wastewater ◽

Butyl Ether ◽

Tert Butyl ◽

Tert Butyl Alcohol

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Methyl tert-butyl Ether and tert-butyl Alcohol Degradation by Fusarium solani

Biotechnology Letters ◽

10.1007/s10529-005-3729-y ◽

2005 ◽

Vol 27 (22) ◽

pp. 1797-1801 ◽

Cited By ~ 11

Author(s):

Miguel Magaña-Reyes ◽

Marcia Morales ◽

Sergio Revah

Keyword(s):

Fusarium Solani ◽

Butyl Alcohol ◽

Methyl Tert Butyl Ether ◽

Butyl Ether ◽

Tert Butyl ◽

Tert Butyl Alcohol

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Biodegradation of Methyl tert-Butyl Ether by a Pure Bacterial Culture

Applied and Environmental Microbiology ◽

10.1128/aem.67.12.5601-5607.2001 ◽

2001 ◽

Vol 67 (12) ◽

pp. 5601-5607 ◽

Cited By ~ 105

Author(s):

Paul B. Hatzinger ◽

Kevin McClay ◽

Simon Vainberg ◽

Marina Tugusheva ◽

Charles W. Condee ◽

...

Keyword(s):

Bacterial Culture ◽

Butyl Alcohol ◽

The Other ◽

Methyl Tert Butyl Ether ◽

Butyl Ether ◽

Pure Bacterial Culture ◽

Degradation Activity ◽

Type Strains ◽

Mtbe Degradation ◽

Allyl Thiourea

ABSTRACT Biodegradation of methyl tert-butyl ether (MTBE) by the hydrogen-oxidizing bacterium Hydrogenophaga flavaENV735 was evaluated. ENV735 grew slowly on MTBE ortert-butyl alcohol (TBA) as sole sources of carbon and energy, but growth on these substrates was greatly enhanced by the addition of a small amount of yeast extract. The addition of H2 did not enhance or diminish MTBE degradation by the strain, and MTBE was only poorly degraded or not degraded by type strains of Hydrogenophaga or hydrogen-oxidizing enrichment cultures, respectively. MTBE degradation activity was constitutively expressed in ENV735 and was not greatly affected by formaldehyde, carbon monoxide, allyl thiourea, or acetylene. MTBE degradation was inhibited by 1-amino benzotriazole and butadiene monoepoxide. TBA degradation was inducible by TBA and was inhibited by formaldehyde at concentrations of >0.24 mM and by acetylene but not by the other inhibitors tested. These results demonstrate that separate, independently regulated genes encode MTBE and TBA metabolism in ENV735.

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Metabolism of 2-Methylpropene (Isobutylene) by the Aerobic Bacterium Mycobacterium sp. Strain ELW1

Applied and Environmental Microbiology ◽

10.1128/aem.03103-14 ◽

2015 ◽

Vol 81 (6) ◽

pp. 1966-1976 ◽

Cited By ~ 14

Author(s):

Samanthi Kottegoda ◽

Elizabeth Waligora ◽

Michael Hyman

Keyword(s):

Dry Weight ◽

Microbial Metabolism ◽

Sole Source ◽

Butyl Alcohol ◽

Lag Phase ◽

Aerobic Bacterium ◽

Butyl Ether ◽

Content Type ◽

Cobalt Ions ◽

Alkene Oxidation

ABSTRACTAn aerobic bacterium (Mycobacteriumsp. strain ELW1) that utilizes 2-methylpropene (isobutylene) as a sole source of carbon and energy was isolated and characterized. Strain ELW1 grew on 2-methylpropene (growth rate = 0.05 h−1) with a yield of 0.38 mg (dry weight) mg 2-methylpropene−1. Strain ELW1 also grew more slowly on bothcis- andtrans-2-butene but did not grow on any other C2to C5straight-chain, branched, or chlorinated alkenes tested. Resting 2-methylpropene-grown cells consumed ethene, propene, and 1-butene without a lag phase. Epoxyethane accumulated as the only detected product of ethene oxidation. Both alkene consumption and epoxyethane production were fully inhibited in cells exposed to 1-octyne, suggesting that alkene oxidation is initiated by an alkyne-sensitive, epoxide-generating monooxygenase. Kinetic analyses indicated that 1,2-epoxy-2-methylpropane is rapidly consumed during 2-methylpropene degradation, while 2-methyl-2-propen-1-ol is not a significant metabolite of 2-methylpropene catabolism. Degradation of 1,2-epoxy-2-methylpropane by 2-methylpropene-grown cells led to the accumulation and further degradation of 2-methyl-1,2-propanediol and 2-hydroxyisobutyrate, two sequential metabolites previously identified in the aerobic microbial metabolism of methyltert-butyl ether (MTBE) andtert-butyl alcohol (TBA). Growth of strain ELW1 on 2-methylpropene, 1,2-epoxy-2-methylpropane, 2-methyl-1,2-propanediol, and 2-hydroxyisobutyrate was fully inhibited when cobalt ions were omitted from the growth medium, while growth on 3-hydroxybutyrate and other substrates was unaffected by the absence of added cobalt ions. Our results suggest that, like aerobic MTBE- and TBA-metabolizing bacteria, strain ELW1 utilizes a cobalt/cobalamin-dependent mutase to transform 2-hydroxyisobutyrate. Our results have been interpreted in terms of their impact on our understanding of the microbial metabolism of alkenes and ether oxygenates.

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