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Wackett LP. Strategies for the Biodegradation of Polyfluorinated Compounds. Microorganisms 2022; 10:1664. [PMID: 36014082 PMCID: PMC9415301 DOI: 10.3390/microorganisms10081664] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 08/14/2022] [Accepted: 08/16/2022] [Indexed: 01/01/2023] Open
Abstract
Many cite the strength of C-F bonds for the poor microbial biodegradability of polyfluorinated organic compounds (PFCs). However, commercial PFCs almost invariably contain more functionality than fluorine. The additional functionality provides a weak entry point for reactions that activate C-F bonds and lead to their eventual cleavage. This metabolic activation strategy is common in microbial biodegradation pathways and is observed with aromatic hydrocarbons, chlorinated compounds, phosphonates and many other compounds. Initial metabolic activation precedes critical bond breakage and assimilation of nutrients. A similar strategy with commercial PFCs proceeds via initial attack at the non-fluorinated functionalities: sulfonates, carboxylates, chlorines, phenyl rings, or phosphonates. Metabolic transformation of these non-fluorinated groups can activate the C-F bonds, allowing more facile cleavage than a direct attack on the C-F bonds. Given that virtually all compounds denoted as "PFAS" are not perfluorinated and are not alkanes, it is posited here that considering their individual chemical classes is more useful for both chemical and microbiological considerations of their fate.
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Affiliation(s)
- Lawrence P Wackett
- Department of Biochemistry, Molecular Biology and Biophysics and BioTechnology Institute, University of Minnesota, Minneapolis, MN 55455, USA
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2
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Bygd MD, Aukema KG, Richman JE, Wackett LP. Microwell Fluoride Screen for Chemical, Enzymatic, and Cellular Reactions Reveals Latent Microbial Defluorination Capacity for -CF 3 Groups. Appl Environ Microbiol 2022; 88:e0028822. [PMID: 35435713 PMCID: PMC9088286 DOI: 10.1128/aem.00288-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 03/29/2022] [Indexed: 12/11/2022] Open
Abstract
The capacity to defluorinate polyfluorinated organic compounds is a rare phenotype in microbes but is increasingly considered important for maintaining the environment. New discoveries will be greatly facilitated by the ability to screen many natural and engineered microbes in a combinatorial manner against large numbers of fluorinated compounds simultaneously. Here, we describe a low-volume, high-throughput screening method to determine defluorination capacity of microbes and their enzymes. The method is based on selective binding of fluoride to a lanthanum chelate complex that gives a purple-colored product. It was miniaturized to determine biodefluorination in 96-well microtiter plates by visual inspection or robotic handling and spectrophotometry. Chemicals commonly used in microbiological studies were examined to define usable buffers and reagents. Base-catalyzed, purified enzyme and whole-cell defluorination reactions were demonstrated with fluoroatrazine and showed correspondence between the microtiter assay and a fluoride electrode. For discovering new defluorination reactions and mechanisms, a chemical library of 63 fluorinated compounds was screened in vivo with Pseudomonas putida F1 in microtiter well plates. These data were also calibrated against a fluoride electrode. Our new method revealed 21 new compounds undergoing defluorination. A compound with four fluorine substituents, 4-fluorobenzotrifluoride, was shown to undergo defluorination to the greatest extent. The mechanism of its defluorination was studied to reveal a latent microbial propensity to defluorinate trifluoromethylphenyl groups, a moiety that is commonly incorporated into numerous pharmaceutical and agricultural chemicals. IMPORTANCE Thousands of organofluorine chemicals are known, and a number are considered to be persistent and toxic environmental pollutants. Environmental bioremediation methods are avidly being sought, but few bacteria biodegrade fluorinated chemicals. To find new organofluoride biodegradation, a rapid screening method was developed. The method is versatile, monitoring chemical, enzymatic, and whole-cell biodegradation. Biodegradation of organofluorine compounds invariably releases fluoride anions, which was sensitively detected. Our method uncovered 21 new microbial defluorination reactions. A general mechanism was delineated for the biodegradation of trifluoromethylphenyl groups that are increasingly being used in drugs and pesticides.
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Affiliation(s)
- Madison D. Bygd
- Microbial Engineering, University of Minnesota, Minneapolis, Minnesota, USA
- Biotechnology Institute, University of Minnesota, Minneapolis, Minnesota, USA
| | - Kelly G. Aukema
- Biotechnology Institute, University of Minnesota, Minneapolis, Minnesota, USA
- Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
| | - Jack E. Richman
- Biotechnology Institute, University of Minnesota, Minneapolis, Minnesota, USA
- Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
| | - Lawrence P. Wackett
- Microbial Engineering, University of Minnesota, Minneapolis, Minnesota, USA
- Biotechnology Institute, University of Minnesota, Minneapolis, Minnesota, USA
- Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, Minnesota, USA
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3
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Wackett LP. Pseudomonas: Versatile Biocatalysts for PFAS. Environ Microbiol 2022; 24:2882-2889. [PMID: 35384226 DOI: 10.1111/1462-2920.15990] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 11/28/2022]
Affiliation(s)
- Lawrence P Wackett
- Microbial Engineering, University of Minnesota.,Biotechnology Institute, University of Minnesota.,Biochemistry, Molecular Biology and Biophysics, University of Minnesota
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4
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Pérez-Ruiz R, Molins-Molina O, Lence E, González-Bello C, Miranda MA, Jiménez MC. Photogeneration of Quinone Methides as Latent Electrophiles for Lysine Targeting. J Org Chem 2018; 83:13019-13029. [PMID: 30274513 DOI: 10.1021/acs.joc.8b01559] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Latent electrophiles are nowadays very attractive chemical entities for drug discovery, as they are unreactive unless activated upon binding with the specific target. In this work, the utility of 4-trifluoromethyl phenols as precursors of latent electrophiles, quinone methides (QM), for lysine-targeting is demonstrated. These Michael acceptors were photogenerated for specific covalent modification of lysine residues using human serum albumin (HSA) as a model target. The reactive QM-type intermediates I or II, generated upon irradiation of 4-trifluoromethyl-1-naphthol (1)@HSA or 4-(4-trifluorometylphenyl)phenol (2)@HSA complexes, exhibited chemoselective reactivity toward lysine residues leading to amide adducts, which was confirmed by proteomic analysis. For ligand 1, the covalent modification of residues Lys106 and Lys414 (located in subdomains IA and IIIA, respectively) was observed, whereas for ligand 2, the modification of Lys195 (in subdomain IIA) took place. Docking and molecular dynamics simulation studies provided an insight into the molecular basis of the selectivity of 1 and 2 for these HSA subdomains and the covalent modification mechanism. These studies open the opportunity of performing protein silencing by generating reactive ligands under very mild conditions (irradiation) for specific covalent modification of hidden lysine residues.
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Affiliation(s)
- Raúl Pérez-Ruiz
- Departamento de Química, Instituto de Tecnología Química UPV-CSIC , Universitat Politécnica de València , Camino de Vera s/n , 46071 Valencia , Spain.,Photoactivated Processes Unit , IMDEA Energy Institute , Av. Ramón de la Sagra 3 , 28935 Móstoles, Madrid , Spain
| | - Oscar Molins-Molina
- Departamento de Química, Instituto de Tecnología Química UPV-CSIC , Universitat Politécnica de València , Camino de Vera s/n , 46071 Valencia , Spain
| | - Emilio Lence
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS), Departamento de Química Orgánica , Universidade de Santiago de Compostela , Jenaro de la Fuente s/n , 15782 Santiago de Compostela , Spain
| | - Concepción González-Bello
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS), Departamento de Química Orgánica , Universidade de Santiago de Compostela , Jenaro de la Fuente s/n , 15782 Santiago de Compostela , Spain
| | - Miguel A Miranda
- Departamento de Química, Instituto de Tecnología Química UPV-CSIC , Universitat Politécnica de València , Camino de Vera s/n , 46071 Valencia , Spain
| | - M Consuelo Jiménez
- Departamento de Química, Instituto de Tecnología Química UPV-CSIC , Universitat Politécnica de València , Camino de Vera s/n , 46071 Valencia , Spain
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Microbial degradation of fluorinated drugs: biochemical pathways, impacts on the environment and potential applications. Appl Microbiol Biotechnol 2016; 100:2617-27. [PMID: 26830103 DOI: 10.1007/s00253-016-7304-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Revised: 01/05/2016] [Accepted: 01/07/2016] [Indexed: 12/25/2022]
Abstract
Since the discovery over 60 years ago of fluorocortisone's biological properties (9-α-Fluoro derivatives of cortisone and hydrocortisone; Fried J and Sabo EF, J Am Chem Soc 76: 1455-1456, 1954), the number of fluorinated drugs has steadily increased. With the improvement in synthetic methodologies, this trend is likely to continue and will lead to the introduction of new fluorinated substituents into pharmaceutical compounds. Although the biotransformation of organofluorine compounds by microorganisms has been well studied, specific investigations on fluorinated drugs are relatively few, despite the increase in the number and variety of fluorinated drugs that are available. The strength of the carbon-fluorine bond conveys stability to fluorinated drugs; thus, they are likely to be recalcitrant in the environment or may be partially metabolized to a more toxic metabolite. This review examines the research done on microbial biotransformation and biodegradation of fluorinated drugs and highlights the importance of understanding how microorganisms interact with this class of compound from environmental, clinical and biotechnological perspectives.
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Kavanagh E, Winn M, Gabhann CN, O'Connor NK, Beier P, Murphy CD. Microbial biotransformation of aryl sulfanylpentafluorides. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:753-758. [PMID: 23872898 DOI: 10.1007/s11356-013-1985-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 07/02/2013] [Indexed: 06/02/2023]
Abstract
We report, for the first time, the biotransformation of potential pollutants bearing the pentafluorosulfanyl (SF5-) functional group in a fungus and bacteria. Cunninghamella elegans transformed p-methoxy phenyl SF5 via demethylation; Pseudomonas knackmussii and P. pseudoalcaligenes KF707 transformed amino-, hydroxyamino- and diamino- substituted phenyl SF5, forming the N-acetylated derivatives as the main product. Cell-free extract of Streptomyces griseus transformed 4-amino-3-hydroxy-phenyl SF5 to the N-acetylated derivative in the presence of acetyl CoA, confirming that an N-acetyltransferase is responsible for the bacterial biotransformations. Approximately 25% of drugs and 30% of agrochemicals contain fluorine, and the trifluoromethyl group is a prominent feature of many of these since it improves lipophilicity and stability. The pentafluorosulfanyl substituent is seen as an improvement on the trifluoromethyl group and research efforts are underway to develop synthetic methods to incorporate this moiety into biologically active compounds. It is important to determine the potential environmental impact of these compounds, including the potential biotransformation reactions that may occur when they are exposed to microorganisms.
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Affiliation(s)
- Emma Kavanagh
- School of Biomolecular and Biomedical Science, Centre for Synthesis and Chemical Biology, Ardmore House, University College Dublin, Dublin, Ireland
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Isolation, identification and characterization of a novel Ralstonia sp. FD-1, capable of degrading 4-fluoroaniline. Biodegradation 2013; 25:85-94. [PMID: 23604516 DOI: 10.1007/s10532-013-9642-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 04/12/2013] [Indexed: 10/26/2022]
Abstract
A gram-negative strain, designated as FD-1, isolated from aerobic activated sludge was capable of metabolizing 4-fluoroaniline (4-FA) as its sole carbon and nitrogen source and energy supply. According to the Biolog GNIII detection method 17 of 71 carbon substrates were easily utilized, while 12 of 23 substrates did not inhibit strain FD-1. The 16S rDNA sequence from strain FD-1 was 99 % similar to Ralstonia sp., suggesting that it belonged to the genus Ralstonia. The optimal conditions for growth and 4-FA degradation were pH 7 and 30 °C. The tolerance to 4-FA were 1,250 mg/L, while the tolerance to salinity was 15 g/L. Catechol 2,3-dioxygenase activity was detected and degradation intermediates were analyzed by liquid chromatography mass spectrometry leading to a proposed degradation pathway and suggesting that extradiol cleavage was involved in 4-FA degradation. This is the first report on the degradation of 4-FA by a bacterium from the Ralstonia genus.
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Semak V, Metcalf TA, Endoma-Arias MAA, Mach P, Hudlicky T. Toluene dioxygenase mediated oxidation of halogen-substituted benzoate esters. Org Biomol Chem 2012; 10:4407-16. [PMID: 22562668 DOI: 10.1039/c2ob25202c] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of ortho-, meta-, and para- halogen-substituted methyl benzoate esters was subjected to enzymatic dihydroxylation via the whole-cell fermentation with E. coli JM109 (pDTG601A). Only ortho-substituted benzoates were metabolized. Methyl 2-fluorobenzoate yielded one diol regioselectively whereas methyl 2-chloro-, methyl 2-bromo- and methyl 2-iodobenzoates each yielded a mixture of regioisomers. Absolute stereochemistry was determined for all new metabolites. Computational analysis of these results and a possible rationale for the regioselectivity of the enzymatic dihydroxylation is advanced.
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Affiliation(s)
- Vladislav Semak
- Department of Chemistry, Brock University, 500 Glenridge Ave, St. Catharines, ON, Canada L2S 3A1
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Griffen JA, Le Coz AM, Kociok-Köhn G, Khan MA, Stewart AJW, Lewis SE. Expanding the chiral pool: oxidation of meta-bromobenzoic acid by R. eutrophus B9 allows access to new reaction manifolds. Org Biomol Chem 2011; 9:3920-8. [DOI: 10.1039/c1ob05131h] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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11
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Production of human metabolites of the anti-cancer drug flutamide via biotransformation in Cunninghamella species. Biotechnol Lett 2010; 33:321-6. [PMID: 20931353 DOI: 10.1007/s10529-010-0425-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Accepted: 09/23/2010] [Indexed: 10/19/2022]
Abstract
Fungi belonging to the genus Cunninghamella have enzymes similar to those employed by mammals for the detoxification of xenobiotics, thus they are useful as models of mammalian drug metabolism, and as a source for drug metabolites. We report the transformation of the anti-cancer drug flutamide in Cunninghamella sp. The most predominant phase I metabolites present in the plasma of humans, 2-hydroxyflutamide and 4-nitro-3-(trifluoromethyl)aniline, were also produced in Cunninghamella cultures. Other phase I and phase II metabolites were also detected using a combination of HPLC, GC-MS and (19)F-NMR.
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12
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Murphy CD. Biodegradation and biotransformation of organofluorine compounds. Biotechnol Lett 2009; 32:351-9. [DOI: 10.1007/s10529-009-0174-3] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2009] [Revised: 11/06/2009] [Accepted: 11/09/2009] [Indexed: 10/20/2022]
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13
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Metabolism of fluoroorganic compounds in microorganisms: impacts for the environment and the production of fine chemicals. Appl Microbiol Biotechnol 2009; 84:617-29. [PMID: 19629474 DOI: 10.1007/s00253-009-2127-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Revised: 07/02/2009] [Accepted: 07/02/2009] [Indexed: 10/20/2022]
Abstract
Incorporation of fluorine into an organic compound can favourably alter its physicochemical properties with respect to biological activity, stability and lipophilicity. Accordingly, this element is found in many pharmaceutical and industrial chemicals. Organofluorine compounds are accepted as substrates by many enzymes, and the interactions of microorganisms with these compounds are of relevance to the environment and the fine chemicals industry. On the one hand, the microbial transformation of organofluorines can lead to the generation of toxic compounds that are of environmental concern, yet similar biotransformations can yield difficult-to-synthesise products and intermediates, in particular derivatives of biologically active secondary metabolites. In this paper, we review the historical and recent developments of organofluorine biotransformation in microorganisms and highlight the possibility of using microbes as models of fluorinated drug metabolism in mammals.
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Sträuber H, Hübschmann T, Jehmlich N, Schmidt F, von Bergen M, Harms H, Müller S. NBDT (3-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-3-toluene)-A novel fluorescent dye for studying mechanisms of toluene uptake into vital bacteria. Cytometry A 2009; 77:113-20. [DOI: 10.1002/cyto.a.20811] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Guha PK, Saha J, Chaudhuri S, Pal S, Bhattacharyya A, Adityachaudhury N. Investigation on the transformation of fluchloralin by soil fungi: Identification of some metabolites. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/ps.2780440203] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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16
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Yildirim S, Ruinatscha R, Gross R, Wohlgemuth R, Kohler HPE, Witholt B, Schmid A. Selective hydrolysis of the nitrile group of cis-dihydrodiols from aromatic nitriles. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.molcatb.2005.11.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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17
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Chaignon P, Cortial S, Guerineau V, Adeline MT, Giannotti C, Fan G, Ouazzani J. Photochemical Reactivity of Trifluoromethyl Aromatic Amines: The Example of 3,5-diamino-trifluoromethyl-benzene (3,5-DABTF). Photochem Photobiol 2005; 81:1539-43. [PMID: 16149858 DOI: 10.1562/2005-08-03-ra-637] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This work presents the application of an on-line photoreactor to the detection of 3,5-diamino-trifluoromethyl-benzene (3,5-DABTF) in aqueous solutions. When irradiated at 310 nm, this compound is defluorinated to 3,5-diaminobenzoic acid by a nucleophilic substitution of the fluoride by water. Concomitantly, defluorination intermediates polymerize through amide bonds to give dark-colored compounds. We take advantage of the photocatalyzed defluorination and the subsequent decrease in pH to develop an original and specific photoreactor. Continuous recording of pH and temperature in the outlet of the reactor by a dual electrode gives us an opportunity to optimize the system. In the photoreactor, 3,5-DABTF is immediately and totally transformed as attested by the rapid drop of the flowing solution pH from 6.2 to 3.2 and the chromatographic analysis of the outgoing solutions. The detection remains effective from 1 to 1000 parts per million.
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Affiliation(s)
- Philippe Chaignon
- Institut de Chimie des Substances Naturelles, C.N.R.S, Avenue de la Terrasse, 91198, Gif-sur-Yvette cedex, France
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18
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Clingenpeel SR, Keener WK, Keller CR, De Jesus K, Howard MH, Watwood ME. Activity-dependent fluorescent labeling of bacterial cells expressing the TOL pathway. J Microbiol Methods 2005; 60:41-6. [PMID: 15567223 DOI: 10.1016/j.mimet.2004.08.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2004] [Revised: 08/03/2004] [Accepted: 08/23/2004] [Indexed: 11/17/2022]
Abstract
3-Ethynylbenzoate (3EB) functions as a novel, activity-dependent, fluorogenic, and chromogenic probe for bacterial strains expressing the TOL pathway, which degrade toluene via conversion to benzoate, followed by meta ring fission of the intermediate catechol. This direct physiological analysis allows the fluorescent labeling of cells whose toluene-degrading enzymes have been induced by an aromatic substrate.
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Affiliation(s)
- Scott R Clingenpeel
- Department of Biological Sciences, Idaho State University, Pocatello, ID 83209, USA
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Van Hamme JD, Fedorak PM, Foght JM, Gray MR, Dettman HD. Use of a novel fluorinated organosulfur compound to isolate bacteria capable of carbon-sulfur bond cleavage. Appl Environ Microbiol 2004; 70:1487-93. [PMID: 15006770 PMCID: PMC368330 DOI: 10.1128/aem.70.3.1487-1493.2004] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The vacuum residue fraction of heavy crudes contributes to the viscosity of these oils. Specific microbial cleavage of C-S bonds in alkylsulfide bridges that form linkages in this fraction may result in dramatic viscosity reduction. To date, no bacterial strains have been shown conclusively to cleave C-S bonds within alkyl chains. Screening for microbes that can perform this activity was greatly facilitated by the use of a newly synthesized compound, bis-(3-pentafluorophenylpropyl)-sulfide (PFPS), as a novel sulfur source. The terminal pentafluorinated aromatic rings of PFPS preclude growth of aromatic ring-degrading bacteria but allow for selective enrichment of strains capable of cleaving C-S bonds. A unique bacterial strain, Rhodococcus sp. strain JVH1, that used PFPS as a sole sulfur source was isolated from an oil-contaminated environment. Gas chromatography-mass spectrometry analysis revealed that JVH1 oxidized PFPS to a sulfoxide and then a sulfone prior to cleaving the C-S bond to form an alcohol and, presumably, a sulfinate from which sulfur could be extracted for growth. Four known dibenzothiophene-desulfurizing strains, including Rhodococcus sp. strain IGTS8, were all unable to cleave the C-S bond in PFPS but could oxidize PFPS to the sulfone via the sulfoxide. Conversely, JVH1 was unable to oxidize dibenzothiophene but was able to use a variety of alkyl sulfides, in addition to PFPS, as sole sulfur sources. Overall, PFPS is an excellent tool for isolating bacteria capable of cleaving subterminal C-S bonds within alkyl chains. The type of desulfurization displayed by JVH1 differs significantly from previously described reaction results.
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Keener WK, Watwood ME, Schaller KD, Walton MR, Partin JK, Smith WA, Clingenpeel SR. Use of selective inhibitors and chromogenic substrates to differentiate bacteria based on toluene oxygenase activity. J Microbiol Methods 2001; 46:171-85. [PMID: 11438182 DOI: 10.1016/s0167-7012(01)00266-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In whole-cell studies, two alkynes, 1-pentyne and phenylacetylene, were selective, irreversible inhibitors of monooxygenase enzymes in catabolic pathways that permit growth of bacteria on toluene. 1-Pentyne selectively inhibited growth of Burkholderia cepacia G4 (toluene 2-monooxygenase [T2MO] pathway) and B. pickettii PKO1 (toluene 3-monooxygenase [T3MO] pathway) on toluene, but did not inhibit growth of bacteria expressing other pathways. In further studies with strain G4, chromogenic transformation of alpha,alpha,alpha-Trifluoro-m-cresol (TFC) was irreversibly inhibited by 1-pentyne, but the presence of phenol prevented this inhibition. Transformation of catechol by G4 was unaffected by 1-pentyne. With respect to the various pathways and bacteria tested, phenylacetylene selectively inhibited growth of Pseudomonas mendocina KR1 (toluene 4-monooxygenase [T4MO] pathway) on toluene, but not on p-cresol. An Escherichia coli transformant expressing T4MO transformed indole or naphthalene in chromogenic reactions, but not after exposure to phenylacetylene. The naphthalene reaction remained diminished in phenylacetylene-treated cells relative to untreated cells after phenylacetylene was removed, indicating irreversible inhibition.These techniques were used to differentiate toluene-degrading isolates from an aquifer. Based on data generated with these indicators and inhibitors, along with results from Biolog analysis for sole carbon source oxidation, the groundwater isolates were assigned to eight separate groups, some of which apparently differ in their mode of toluene catabolism.
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Affiliation(s)
- W K Keener
- Idaho National Engineering and Environmental Laboratory, P.O. Box 1625, Idaho Falls, ID 83415-2203, USA
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21
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Production of 4,5-dihydroxyphthalate by Pseudomonas testosteroni immobilized in alginate gel beads. Biochem Eng J 1999. [DOI: 10.1016/s1369-703x(99)00008-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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23
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Sharp RR, Bryers JD, Jones WG, Shields MS. Activity and stability of a recombinant plasmid-borne TCE degradative pathway in suspended cultures. Biotechnol Bioeng 1998. [DOI: 10.1002/(sici)1097-0290(19980205)57:3<287::aid-bit5>3.0.co;2-d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Abstract
Rhodococci display a diverse range of metabolic capabilities and they are a ubiquitous feature of many environments. They are able to degrade short-chain, long-chain, and halogenated hydrocarbons, and numerous aromatic compounds, including halogenated and other substituted aromatics, heteroaromatics, hydroaromatics, and polycyclic aromatic hydrocarbons. They possess a wide variety of pathways for degrading and modifying aromatic compounds, including dioxygenase and monooxygenase ring attack, and cleavage of catechol by both ortho- and meta-routes, and some strains possess a modified 3-oxoadipate pathway. Biotransformations catalyzed by rhodococci include steroid modification, enantioselective synthesis, and the transformation of nitriles to amides and acids. Tolerance of rhodococci to starvation, their frequent lack of catabolite repression, and their environmental persistence make them excellent candidates for bioremediation treatments. Some strains can produce poly(3-hydroxyalkanoate)s, others can accumulate cesium, and still others are the source of useful enzymes such as phenylalanine dehydrogenase and endoglycosidases. Other actual or potential applications of rhodococci include desulfurization of coal, bioleaching, use of their surfactants in enhancement of oil recovery and as industrial dispersants, and the construction of biosensors.
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Affiliation(s)
- A M Warhurst
- Department of Biochemistry, University of Glasgow, U.K
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Taylor BF, Amador JA, Levinson HS. Degradation of meta-trifluoromethylbenzoate by sequential microbial and photochemical treatments. FEMS Microbiol Lett 1993; 110:213-6. [PMID: 8349093 DOI: 10.1111/j.1574-6968.1993.tb06322.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
m- and p-trifluoromethyl (TFM)-benzoates are incompletely degraded by aerobic bacteria that catabolize alkylbenzoates; biodegradation ceases after ring-fission with the accumulation of a trifluoromethyl muconate semialdehyde (2-hydroxy-6-oxo-7,7,7-trifluorohepta-2,4-dienoate, TFHOD) which is resistant to biochemical attack. A bacterium (Strain V-1), isolated from sea-water, grew aerobically on benzoate or m-toluate. Cells grown on benzoate or m-toluate oxidized both compounds at similar relative rates. Catabolism involved benzoate 1,2-dioxygenase (decarboxylating) and meta-cleavage to yield muconate semialdehydes. Cells grown on benzoate metabolized m-TFM-benzoate to TFHOD. The ring-fission products from m-toluate and TFHOD were degraded by sunlight, and equimolar fluoride was released from TFHOD. Sequential biochemical and photochemical treatment allowed the destruction of m-TFM-benzoate beyond the biochemically recalcitrant intermediate TFHOD.
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Affiliation(s)
- B F Taylor
- Division of Marine and Atmospheric Chemistry, Rosenstiel School of Marine and Atmospheric Science, University of Miami, FL 33149-1098
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Shields MS, Reagin MJ. Selection of a Pseudomonas cepacia strain constitutive for the degradation of trichloroethylene. Appl Environ Microbiol 1992; 58:3977-83. [PMID: 1282314 PMCID: PMC183214 DOI: 10.1128/aem.58.12.3977-3983.1992] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Tn5 insertion mutants of Pseudomonas cepacia G4 that were unable to degrade trichloroethylene (TCE), toluene, or phenol or to transform m-trifluoromethyl phenol (TFMP) to 7,7,7-trifluoro-2-hydroxy-6-oxo-2,4-heptadienoic acid (TFHA) were produced. Spontaneous reversion to growth on phenol or toluene as the sole source of carbon was observed in one mutant strain, G4 5223, at a frequency of approximately 1 x 10(-4) per generation. One such revertant, G4 5223-PR1, metabolized TFMP to TFHA and degraded TCE. Unlike wild-type G4, G4 5223-PR1 constitutively metabolized both TFMP and TCE without aromatic induction. G4 5223-PR1 also degraded cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, and 1,1-dichloroethylene and oxidized naphthalene to alpha naphthol constitutively. G4 5223-PR1 exhibited a slight retardation in growth rate at TCE concentrations of > or = 530 microM, whereas G4 (which was unable to metabolize TCE under the same noninducing growth conditions) remained unaffected. The constitutive degradative phenotype of G4 5223-PR1 was completely stable through 100 generations of nonselective growth.
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Affiliation(s)
- M S Shields
- Center for Environmental Diagnostics and Bioremediation, University of West Florida, Pensacola 32514-5751
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Shields MS, Montgomery SO, Cuskey SM, Chapman PJ, Pritchard PH. Mutants of Pseudomonas cepacia G4 defective in catabolism of aromatic compounds and trichloroethylene. Appl Environ Microbiol 1991; 57:1935-41. [PMID: 1892384 PMCID: PMC183502 DOI: 10.1128/aem.57.7.1935-1941.1991] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Pseudomonas cepacia G4 possesses a novel pathway of toluene catabolism that is shown to be responsible for the degradation of trichloroethylene (TCE). This pathway involves conversion of toluene via o-cresol to 3-methylcatechol. In order to determine the enzyme of toluene degradation that is responsible for TCE degradation, chemically induced mutants, blocked in the toluene ortho-monooxygenase (TOM) pathway of G4, were examined. Mutants of the phenotypic class designated TOM A- were all defective in their ability to oxidize toluene, o-cresol, m-cresol, and phenol, suggesting that a single enzyme is responsible for conversion of these compounds to their hydroxylated products (3-methylcatechol from toluene, o-cresol, and m-cresol and catechol from phenol) in the wild type. Mutants of this class did not degrade TCE. Two other mutant classes which were blocked in toluene catabolism, TOM B-, which lacked catechol-2,3-dioxygenase, and TOM C-, which lacked 2-hydroxy-6-oxoheptadienoic acid hydrolase activity, were fully capable of TCE degradation. Therefore, TCE degradation is directly associated with the monooxygenation capability responsible for toluene, cresol, and phenol hydroxylation.
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Affiliation(s)
- M S Shields
- Technical Resources Inc., Gulf Breeze, Florida
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Engesser KH, Auling G, Busse J, Knackmuss HJ. 3-Fluorobenzoate enriched bacterial strain FLB 300 degrades benzoate and all three isomeric monofluorobenzoates. Arch Microbiol 1990. [DOI: 10.1007/bf00247820] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Engesser K, Strubel V, Christoglou K, Fischer P, Rast H. Dioxygenolytic cleavage of aryl ether bonds: 1, 10-dihydro-1, 10-dihydroxyfluoren-9-one, a novel arene dihydrodiol as evidence for angular dioxygenation of dibenzofuran. FEMS Microbiol Lett 1989. [DOI: 10.1111/j.1574-6968.1989.tb03623.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Affiliation(s)
- R S Burlage
- Department of Microbiology, University of Tennessee, Knoxville 37996
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Engesser KH, Rubio MA, Ribbons DW. Bacterial metabolism of side chain fluorinated aromatics: cometabolism of 4-trifluoromethyl(TFM)-benzoate by 4-isopropylbenzoate grown Pseudomonas putida JT strains. Arch Microbiol 1988; 149:198-206. [PMID: 3365097 DOI: 10.1007/bf00422005] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Enzymes of the p-cymene pathway in Pseudomonas putida strains cometabolized the intermediate analogue 4-trifluoromethyl(TFM)benzoate. Three products, 4-TFM-2,3-dihydro-2,3-dihydroxybenzoate, 4-TFM-2,3-dihydroxybenzoate and 2-hydroxy-6-oxo-7,7,7-trifluorohepta-2,4-dienoate (7-TFHOD) were identified chemically and by spectroscopic properties. Certain TFM-substituted analogue metabolites of the p-cymene pathway were transformed at drastically reduced rates. Hammett type analysis of ring cleavage reactions of 4-substituted 2,3-dihydroxybenzoates revealed the negative inductive and especially mesomeric effect of substituents to be rate determining. Whereas decarboxylation of 3-carboxy-7-TFHOD was not affected by fluorine substitution the subsequent hydrolysis of 7-TFHOD proceeded very slowly. The negative inductive effect of the TFM-group probably inhibited heterolysis of the carbon bond between C5 and C6 of 7-TFHOD.
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Affiliation(s)
- K H Engesser
- Institut für Mikrobiologie der Universität Stuttgart, Federal Republic of Germany
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