Biomaterial Database

Aerobic degradation of mixtures of chlorinated aliphatics by cloned toluene-o-xylene monooxygenase and toluene o-monooxygenase in resting cells. 2000

H Shim, and T K Wood

Department of Chemical Engineering, University of Connecticut, 191 Auditorium Road, U-3222, Storrs, Connecticut 06269-3222, USA.

Recombinant strains of Escherichia coli constitutively expressing toluene-o-xylene monooxygenase (ToMO) of Pseudomonas stutzeri OX1 and toluene o-monooxygenase (TOM) of Burkholderia cepacia G4 were investigated for their ability to oxidize trichloroethylene (TCE), 1,1-dichloroethylene (1,1-DCE), cis-1,2-dichloroethylene (cis-DCE), trans-1,2-dichloroethylene (trans-DCE), vinyl chloride (VC), and chloroform (CF), individually as well as in various mixtures. ToMO oxidized all of these individual compounds well, whereas TOM did not degrade VC significantly (16-fold less) and degraded cis-DCE and trans-DCE less well (3.7- and 2.4-fold, respectively). For mixtures of these chlorinated aliphatics, ToMO was again more robust than TOM. For example, in binary mixtures including TCE, ToMO degraded all three DCE isomers and CF, but the presence of TCE inhibited VC degradation; TOM degraded both TCE/1,1-DCE and TCE/trans-DCE, but not cis-DCE for TCE/cis-DCE, and the addition of CF or VC to TCE completely inhibited degradation of both compounds and TCE. The addition of CF or trans-DCE stimulated VC degradation in the presence of TCE for ToMO, and the addition of any of the three DCE isomers stimulated VC degradation for TOM. Significant degradation of all ternary mixtures of TCE and less chlorinated ethenes, as well as a mixture of TCE, three DCEs, and VC, was achieved with ToMO (but not TOM). In mixtures of these chlorinated compounds, degradation was found to occur simultaneously rather than sequentially, and the mineralization of many of these compounds could be confirmed through detection of chloride ions.

UI	MeSH Term	Description	Entries
D010100	Oxygen	An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.	Dioxygen,Oxygen-16,Oxygen 16
D010105	Oxygenases	Oxidases that specifically introduce DIOXYGEN-derived oxygen atoms into a variety of organic molecules.	Oxygenase
D011549	Pseudomonas	A genus of gram-negative, aerobic, rod-shaped bacteria widely distributed in nature. Some species are pathogenic for humans, animals, and plants.	Chryseomonas,Pseudomona,Flavimonas
D002713	Chlorine	An element with atomic symbol Cl, atomic number 17, and atomic weight 35, and member of the halogen family.	Chlorine Gas,Chlorine-35,Cl2 Gas,Chlorine 35,Gas, Chlorine,Gas, Cl2
D002725	Chloroform	A commonly used laboratory solvent. It was previously used as an anesthetic, but was banned from use in the U.S. due to its suspected carcinogenicity.	Trichloromethane
D004000	Dichloroethylenes	Toxic chlorinated unsaturated hydrocarbons. Include both the 1,1- and 1,2-dichloro isomers. Both isomers are toxic, but 1,1-dichloroethylene is the more potent CNS depressant and hepatotoxin. It is used in the manufacture of thermoplastic polymers.	Vinylidene Chlorides,Chlorides, Vinylidene
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D006899	Mixed Function Oxygenases	Widely distributed enzymes that carry out oxidation-reduction reactions in which one atom of the oxygen molecule is incorporated into the organic substrate; the other oxygen atom is reduced and combined with hydrogen ions to form water. They are also known as monooxygenases or hydroxylases. These reactions require two substrates as reductants for each of the two oxygen atoms. There are different classes of monooxygenases depending on the type of hydrogen-providing cosubstrate (COENZYMES) required in the mixed-function oxidation.	Hydroxylase,Hydroxylases,Mixed Function Oxidase,Mixed Function Oxygenase,Monooxygenase,Monooxygenases,Mixed Function Oxidases,Function Oxidase, Mixed,Function Oxygenase, Mixed,Oxidase, Mixed Function,Oxidases, Mixed Function,Oxygenase, Mixed Function,Oxygenases, Mixed Function
D013997	Time Factors	Elements of limited time intervals, contributing to particular results or situations.	Time Series,Factor, Time,Time Factor
D014241	Trichloroethylene	A highly volatile inhalation anesthetic used mainly in short surgical procedures where light anesthesia with good analgesia is required. It is also used as an industrial solvent. Prolonged exposure to high concentrations of the vapor can lead to cardiotoxicity and neurological impairment.	Ethinyl Trichloride,Trichloroethene,Trielina,Trilene,Trichloride, Ethinyl