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Wang Y, Wan S, Yu W, Yuan D, Sun L. Newly isolated Enterobacter cloacae sp. HN01 and Klebsiella pneumoniae sp. HN02 collaborate with self-secreted biosurfactant to improve solubility and bioavailability for the biodegradation of hydrophobic and toxic gaseous para-xylene. CHEMOSPHERE 2022; 304:135328. [PMID: 35700810 DOI: 10.1016/j.chemosphere.2022.135328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 05/23/2022] [Accepted: 06/10/2022] [Indexed: 06/15/2023]
Abstract
The gas-liquid mass transfer rate of hydrophobic volatile organic compounds (VOCs) is the limiting step in a biological treatment system. The present study aimed to utilize self-producing biosurfactants to enhance the bioavailability of hydrophobic gaseous VOCs. Two novel gram-negative rod-shaped bacteria, Enterobacter cloacae strain HN01 and Klebsiella pneumoniae strain HN02 were successfully isolated from sewage sludge by using blood agar and methylene blue agar plates. The two strains can use para-xylene (PX), a hydrophobic VOC model, as the only carbon source for biosurfactant production. Both strains can produce glycolipid biosurfactants, as confirmed by the emulsification index, Nuclear magnetic resonance, and Fourier transform infrared spectroscopy. Results indicated that PX can be completely decomposed at an initial concentration of 15.50 mg L-1, pH value of 7.0, and temperature of 30 °C within 36 h. The Yano model is suitable for the prediction of the growth kinetics of strains over the entire PX concentration range. Gas chromatography/mass spectrometry analysis indicated that PX was converted into four and four intermediates in the presence of the strains HN01 and HN02, respectively, and the possible mechanisms were proposed. The results can be used in purifying industrial hydrophobic gaseous VOCs and improving the bioavailability of VOCs with self-produced biosurfactants.
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Affiliation(s)
- Yan Wang
- School of Chemical Engineering and Technology, Hainan University, Haikou, 570228, China
| | - Shungang Wan
- School of Chemical Engineering and Technology, Hainan University, Haikou, 570228, China; Key Laboratory of Advanced Materials of Tropical Island Resources, Ministry of Education, Haikou, 570228, China
| | - Weili Yu
- College of Ecology and Environment, Hainan University, Haikou, 570228, China
| | - Dan Yuan
- School of Chemical Engineering and Technology, Hainan University, Haikou, 570228, China
| | - Lei Sun
- School of Chemical Engineering and Technology, Hainan University, Haikou, 570228, China; Key Laboratory of Advanced Materials of Tropical Island Resources, Ministry of Education, Haikou, 570228, China.
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Oelschlägel M, Zimmerling J, Tischler D. A Review: The Styrene Metabolizing Cascade of Side-Chain Oxygenation as Biotechnological Basis to Gain Various Valuable Compounds. Front Microbiol 2018; 9:490. [PMID: 29623070 PMCID: PMC5874493 DOI: 10.3389/fmicb.2018.00490] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 03/02/2018] [Indexed: 11/16/2022] Open
Abstract
Styrene is one of the most produced and processed chemicals worldwide and is released into the environment during widespread processing. But, it is also produced from plants and microorganisms. The natural occurrence of styrene led to several microbiological strategies to form and also to degrade styrene. One pathway designated as side-chain oxygenation has been reported as a specific route for the styrene degradation among microorganisms. It comprises the following enzymes: styrene monooxygenase (SMO; NADH-consuming and FAD-dependent, two-component system), styrene oxide isomerase (SOI; cofactor independent, membrane-bound protein) and phenylacetaldehyde dehydrogenase (PAD; NAD+-consuming) and allows an intrinsic cofactor regeneration. This specific way harbors a high potential for biotechnological use. Based on the enzymatic steps involved in this degradation route, important reactions can be realized from a large number of substrates which gain access to different interesting precursors for further applications. Furthermore, stereochemical transformations are possible, offering chiral products at high enantiomeric excess. This review provides an actual view on the microbiological styrene degradation followed by a detailed discussion on the enzymes of the side-chain oxygenation. Furthermore, the potential of the single enzyme reactions as well as the respective multi-step syntheses using the complete enzyme cascade are discussed in order to gain styrene oxides, phenylacetaldehydes, or phenylacetic acids (e.g., ibuprofen). Altered routes combining these putative biocatalysts with other enzymes are additionally described. Thus, the substrates spectrum can be enhanced and additional products as phenylethanols or phenylethylamines are reachable. Finally, additional enzymes with similar activities toward styrene and its metabolic intermediates are shown in order to modify the cascade described above or to use these enzyme independently for biotechnological application.
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Affiliation(s)
- Michel Oelschlägel
- Environmental Microbiology Group, Institute of Biosciences, Technische Universität Bergakademie Freiberg, Freiberg, Germany
| | - Juliane Zimmerling
- Environmental Microbiology Group, Institute of Biosciences, Technische Universität Bergakademie Freiberg, Freiberg, Germany
| | - Dirk Tischler
- Environmental Microbiology Group, Institute of Biosciences, Technische Universität Bergakademie Freiberg, Freiberg, Germany
- Microbial Biotechnology, Ruhr University Bochum, Bochum, Germany
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3
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Biocatalysts for the formation of three- to six-membered carbo- and heterocycles. Biotechnol Adv 2015; 33:457-80. [DOI: 10.1016/j.biotechadv.2015.01.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Accepted: 01/27/2015] [Indexed: 11/18/2022]
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4
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McKenna R, Pugh S, Thompson B, Nielsen DR. Microbial production of the aromatic building-blocks (S)-styrene oxide and (R)-1,2-phenylethanediol from renewable resources. Biotechnol J 2013; 8:1465-75. [DOI: 10.1002/biot.201300035] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Revised: 05/31/2013] [Accepted: 06/25/2013] [Indexed: 11/08/2022]
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5
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Lin H, Liu JY, Wang HB, Ahmed AAQ, Wu ZL. Biocatalysis as an alternative for the production of chiral epoxides: A comparative review. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.molcatb.2011.07.012] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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6
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Leisch H, Morley K, Lau PCK. Baeyer−Villiger Monooxygenases: More Than Just Green Chemistry. Chem Rev 2011; 111:4165-222. [DOI: 10.1021/cr1003437] [Citation(s) in RCA: 317] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Hannes Leisch
- Biotechnology Research Institute, National Research Council Canada, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2, Canada
| | - Krista Morley
- Biotechnology Research Institute, National Research Council Canada, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2, Canada
| | - Peter C. K. Lau
- Biotechnology Research Institute, National Research Council Canada, 6100 Royalmount Avenue, Montreal, Quebec H4P 2R2, Canada
- Department of Microbiology and Immunology, McGill University, 3775 University Street, Montreal, Quebec H3A 2B4, Canada
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7
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Abstract
The development of new catalytic methods to functionalize carbon-hydrogen (C-H) bonds continues to progress at a rapid pace due to the significant economic and environmental benefits of these transformations over traditional synthetic methods. In nature, enzymes catalyze regio- and stereoselective C-H bond functionalization using transformations ranging from hydroxylation to hydroalkylation under ambient reaction conditions. The efficiency of these enzymes relative to analogous chemical processes has led to their increased use as biocatalysts in preparative and industrial applications. Furthermore, unlike small molecule catalysts, enzymes can be systematically optimized via directed evolution for a particular application and can be expressed in vivo to augment the biosynthetic capability of living organisms. While a variety of technical challenges must still be overcome for practical application of many enzymes for C-H bond functionalization, continued research on natural enzymes and on novel artificial metalloenzymes will lead to improved synthetic processes for efficient synthesis of complex molecules. In this critical review, we discuss the most prevalent mechanistic strategies used by enzymes to functionalize non-acidic C-H bonds, the application and evolution of these enzymes for chemical synthesis, and a number of potential biosynthetic capabilities uniquely enabled by these powerful catalysts (110 references).
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Affiliation(s)
| | - Pedro S. Coelho
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd., MC210-41, Pasadena, CA 91125-4100, USA
| | - Frances H. Arnold
- Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd., MC210-41, Pasadena, CA 91125-4100, USA
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Wubbolts MG, Noordman R, van Beilen JB, Witholt B. Enantioselective oxidation by non-heme iron mono-oxygenases from Pseudomonas. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/recl.19951140403] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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9
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Abstract
Whole-cell biocatalysis utilizes native or recombinant enzymes produced by cellular metabolism to perform synthetically interesting reactions. Besides hydrolases, oxidoreductases represent the most applied enzyme class in industry. Oxidoreductases are attributed a high future potential, especially for applications in the chemical and pharmaceutical industries, as they enable highly interesting chemistry (e.g., the selective oxyfunctionalization of unactivated C-H bonds). Redox reactions are characterized by electron transfer steps that often depend on redox cofactors as additional substrates. Their regeneration typically is accomplished via the metabolism of whole-cell catalysts. Traditionally, studies towards productive redox biocatalysis focused on the biocatalytic enzyme, its activity, selectivity, and specificity, and several successful examples of such processes are running commercially. However, redox cofactor regeneration by host metabolism was hardly considered for the optimization of biocatalytic rate, yield, and/or titer. This article reviews molecular mechanisms of oxidoreductases with synthetic potential and the host redox metabolism that fuels biocatalytic reactions with redox equivalents. The tools discussed in this review for investigating redox metabolism provide the basis for studies aiming at a deeper understanding of the interplay between synthetically active enzymes and metabolic networks. The ultimate goal of rational whole-cell biocatalyst engineering and use for fine chemical production is discussed.
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Di L, Accarino M, Bolognese F, Galli E, Barbieri P. Isolation and Metabolic Characterization of a Pseudomonas stutzeri Mutant Able To Grow on the Three Isomers of Xylene. Appl Environ Microbiol 2010; 63:3279-81. [PMID: 16535677 PMCID: PMC1389232 DOI: 10.1128/aem.63.8.3279-3281.1997] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
From an o-xylene-degrading Pseudomonas stutzeri strain (OX1), we previously isolated mutant M1, which had acquired the ability to grow on m-xylene and p-xylene but lost the ability to utilize the ortho isomer. From M1 cultures we have now isolated a revertant strain (R1) which grows on o-xylene and retains the ability to grow with the meta and para isomers regardless of the selective pressure applied. In P. stutzeri R1, o-xylene is degraded through two successive monooxygenations of the aromatic ring, while m-xylene and p-xylene catabolism proceeds through the progressive oxidation of a methyl substituent, although unquantifiable amounts of these two substrates are transformed into the corresponding dimethylphenols, which are not utilized for further growth. The two catabolic pathways are inducible by all three xylene isomers.
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Parales RE, Parales JV, Pelletier DA, Ditty JL. Diversity of microbial toluene degradation pathways. ADVANCES IN APPLIED MICROBIOLOGY 2008; 64:1-73, 2 p following 264. [PMID: 18485280 DOI: 10.1016/s0065-2164(08)00401-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- R E Parales
- Department of Microbiology, University of California, Davis, California 95616, USA
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12
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Nolan LC, O'Connor KE. Dioxygenase- and monooxygenase-catalysed synthesis of cis-dihydrodiols, catechols, epoxides and other oxygenated products. Biotechnol Lett 2008; 30:1879-91. [PMID: 18612597 DOI: 10.1007/s10529-008-9791-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2008] [Revised: 06/20/2008] [Accepted: 06/24/2008] [Indexed: 11/29/2022]
Affiliation(s)
- Louise C Nolan
- School of Biomolecular and Biomedical Science, Centre for Synthesis and Chemical Biology, Conway Institute for Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
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Mooney A, Ward PG, O'Connor KE. Microbial degradation of styrene: biochemistry, molecular genetics, and perspectives for biotechnological applications. Appl Microbiol Biotechnol 2006; 72:1. [PMID: 16823552 DOI: 10.1007/s00253-006-0443-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2006] [Revised: 03/24/2006] [Accepted: 03/27/2006] [Indexed: 10/24/2022]
Abstract
Large quantities of the potentially toxic compound styrene are produced and used annually by the petrochemical and polymer-processing industries. It is as a direct consequence of this that significant volumes of styrene are released into the environment in both the liquid and the gaseous forms. Styrene and its metabolites are known to have serious negative effects on human health and therefore, strategies to prevent its release, remove it from the environment, and understand its route of degradation were the subject of much research. There are a large number of microbial genera capable of metabolizing styrene as a sole source of carbon and energy and therefore, the possibility of applying these organisms to bioremediation strategies was extensively investigated. From the multitude of biodegradation studies, the application of styrene-degrading organisms or single enzymes for the synthesis of value-added products such as epoxides has emerged.
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Affiliation(s)
- Aisling Mooney
- Centre for Synthesis and Chemical Biology, School of Biomolecular and Biomedical Sciences, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland
| | - Patrick G Ward
- Centre for Synthesis and Chemical Biology, School of Biomolecular and Biomedical Sciences, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland
| | - Kevin E O'Connor
- Centre for Synthesis and Chemical Biology, School of Biomolecular and Biomedical Sciences, College of Life Sciences, University College Dublin, Belfield, Dublin 4, Ireland.
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14
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Meyer D, Witholt B, Schmid A. Suitability of recombinant Escherichia coli and Pseudomonas putida strains for selective biotransformation of m-nitrotoluene by xylene monooxygenase. Appl Environ Microbiol 2005; 71:6624-32. [PMID: 16269690 PMCID: PMC1287633 DOI: 10.1128/aem.71.11.6624-6632.2005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Escherichia coli JM101(pSPZ3), containing xylene monooxygenase (XMO) from Pseudomonas putida mt-2, catalyzes specific oxidations and reductions of m-nitrotoluene and derivatives thereof. In addition to reactions catalyzed by XMO, we focused on biotransformations by native enzymes of the E. coli host and their effect on overall biocatalyst performance. While m-nitrotoluene was consecutively oxygenated to m-nitrobenzyl alcohol, m-nitrobenzaldehyde, and m-nitrobenzoic acid by XMO, the oxidation was counteracted by an alcohol dehydrogenase(s) from the E. coli host, which reduced m-nitrobenzaldehyde to m-nitrobenzyl alcohol. Furthermore, the enzymatic background of the host reduced the nitro groups of the reactants resulting in the formation of aromatic amines, which were shown to effectively inhibit XMO in a reversible fashion. Host-intrinsic oxidoreductases and their reaction products had a major effect on the activity of XMO during biocatalysis of m-nitrotoluene. P. putida DOT-T1E and P. putida PpS81 were compared to E. coli JM101 as alternative hosts for XMO. These promising strains contained an additional dehydrogenase that oxidized m-nitrobenzaldehyde to the corresponding acid but catalyzed the formation of XMO-inhibiting aromatic amines at a significantly lower level than E. coli JM101.
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Affiliation(s)
- Daniel Meyer
- University of Dortmund, D-44221 Dortmund, Germany
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15
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Maruyama T, Ishikura M, Taki H, Shindo K, Kasai H, Haga M, Inomata Y, Misawa N. Isolation and characterization of o-xylene oxygenase genes from Rhodococcus opacus TKN14. Appl Environ Microbiol 2005; 71:7705-15. [PMID: 16332743 PMCID: PMC1317363 DOI: 10.1128/aem.71.12.7705-7715.2005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2005] [Accepted: 07/27/2005] [Indexed: 11/20/2022] Open
Abstract
o-Xylene is one of the most difficult-to-degrade environmental pollutants. We report here Rhodococcus genes mediating oxygenation in the first step of o-xylene degradation. Rhodococcus opacus TKN14, isolated from soil contaminated with o-xylene, was able to utilize o-xylene as the sole carbon source and to metabolize it to o-methylbenzoic acid. A cosmid library from the genome of this strain was constructed in Escherichia coli. A bioconversion analysis revealed that a cosmid clone incorporating a 15-kb NotI fragment had the ability to convert o-xylene into o-methylbenzyl alcohol. The sequence analysis of this 15-kb region indicated the presence of a gene cluster significantly homologous to the naphthalene-inducible dioxygenase gene clusters (nidABCD) that had been isolated from Rhodococcus sp. strain I24. Complementation studies, using E. coli expressing various combinations of individual open reading frames, revealed that a gene (named nidE) for rubredoxin (Rd) and a novel gene (named nidF) encoding an auxiliary protein, which had no overall homology with any other proteins, were indispensable for the methyl oxidation reaction of o-xylene, in addition to the dioxygenase iron-sulfur protein genes (nidAB). Regardless of the presence of NidF, the enzyme composed of NidABE was found to function as a typical naphthalene dioxygenase for converting naphthalene and various (di)methylnaphthalenes into their corresponding cis-dihydrodiols. All the nidABEF genes were transcriptionally induced in R. opacus TKN14 by the addition of o-xylene to a mineral salt medium. It is very likely that these genes are involved in the degradation pathways of a wide range of aromatic hydrocarbons by Rhodococcus species as the first key enzyme.
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Affiliation(s)
- Takahiro Maruyama
- Marine Biotechnology Institute, 3-75-1 Heita, Kamaishi, Iwate 026-0001, Japan
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17
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Kim D, Kim YS, Jung JW, Zylstra GJ, Kim YM, Kim SK, Kim E. Regioselective oxidation of xylene isomers by Rhodococcus sp. strain DK17. FEMS Microbiol Lett 2003; 223:211-4. [PMID: 12829288 DOI: 10.1016/s0378-1097(03)00379-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Rhodococcus sp. strain DK17 is able to utilize a variety of monocyclic aromatic hydrocarbons, including benzene, phenol, toluene, and o-xylene, as growth substrates. Although DK17 is unable to grow on m- and p-xylene, this strain could transform these two xylene isomers to some extent after induction by o-xylene. The major accumulating compounds formed during the degradation of m- and p-xylene by DK17 were isolated by high-pressure liquid chromatography and identified by gas chromatography-mass spectrometric and (1)H nuclear magnetic resonance spectral techniques. Both xylene isomers were transformed to dihydroxylated compounds by what must be two successive hydroxylation events: m-xylene was converted to 2,4-dimethylresorcinol and p-xylene was converted to 2,5-dimethylhydroquinone. The rigorous structural identification of 2,4-dimethylresorcinol and 2,5-dimethylhydroquinone demonstrates that DK17 can perform distinct regioselective hydroxylations depending on the position of the substituent groups on the aromatic ring.
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Affiliation(s)
- Dockyu Kim
- Department of Biology and Institute of Life Science and Biotechnology, Yonsei University, Seoul 120-749, South Korea
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Bühler B, Bollhalder I, Hauer B, Witholt B, Schmid A. Use of the two-liquid phase concept to exploit kinetically controlled multistep biocatalysis. Biotechnol Bioeng 2003; 81:683-94. [PMID: 12529882 DOI: 10.1002/bit.10512] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The two-liquid phase concept was used to develop a whole cell biocatalytic system for the efficient multistep oxidation of pseudocumene to 3,4-dimethylbenzaldehyde. Recombinant Escherichia coli cells were employed to express the Pseudomonas putida genes encoding xylene monooxygenase, which catalyzes the multistep oxygenation of one methyl group of toluene and xylenes to corresponding alcohols, aldehydes, and acids. A fed-batch based two-liquid phase bioconversion was established with bis(2-ethylhexyl)- phthalate as organic carrier solvent and a phase ratio of 0.5; the product formation pattern, the impact of the nutrient feeding strategy, and the partitioning behavior of the reactants were studied. On the basis of the favorable conditions provided by the two-liquid phase system, engineering of the initial pseudocumene concentration allowed exploiting the complex kinetics of the multistep reaction for the exclusive production of 3,4-dimethyl- benzaldehyde. Further oxidation of the product to 3,4-dimethylbenzoic acid could be inhibited by suitable concentrations of pseudocumene or 3,4-dimethylbenzyl alcohol. The optimized biotransformation setup includes a completely defined medium with high iron content and a nutrient feeding strategy that avoids severe glucose limitation as well as high inhibitory glucose levels. Using such a system on a 2-liter scale, we were able to produce, within 14.5 h, 30 g of 3,4-dimethylbenzaldehyde as predominant reactant in the organic phase and reached a maximal productivity of 1.6 g per liter liquid volume per hour. The present study implicates that the two-liquid phase concept is an efficient tool to exploit the kinetics of multistep biotransformations in general.
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Affiliation(s)
- Bruno Bühler
- Institute of Biotechnology, Swiss Federal Institute of Technology Zurich, CH-8093 Zurich, Switzerland
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Leahy JG, Tracy KD, Eley MH. Degradation of mixtures of aromatic and chloroaliphatic hydrocarbons by aromatic hydrocarbon-degrading bacteria. FEMS Microbiol Ecol 2003; 43:271-6. [DOI: 10.1111/j.1574-6941.2003.tb01067.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Oxidation of both termini of p- and m-xylene by Escherichia coli transformed with xylene monooxygenase gene. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s1381-1177(02)00225-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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O'Leary ND, O'Connor KE, Dobson ADW. Biochemistry, genetics and physiology of microbial styrene degradation. FEMS Microbiol Rev 2002; 26:403-17. [PMID: 12413667 DOI: 10.1111/j.1574-6976.2002.tb00622.x] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The last few decades have seen a steady increase in the global production and utilisation of the alkenylbenzene, styrene. The compound is of major importance in the petrochemical and polymer-processing industries, which can contribute to the pollution of natural resources via the release of styrene-contaminated effluents and off-gases. This is a cause for some concern as human over-exposure to styrene, and/or its early catabolic intermediates, can have a range of destructive health effects. These features have prompted researchers to investigate routes of styrene degradation in microorganisms, given the potential application of these organisms in bioremediation/biodegradation strategies. This review aims to examine the recent advances which have been made in elucidating the underlying biochemistry, genetics and physiology of microbial styrene catabolism, identifying areas of interest for the future and highlighting the potential industrial importance of individual catabolic pathway enzymes.
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Affiliation(s)
- Niall D O'Leary
- Microbiology Department, National Food Biotechnology Centre, National University of Ireland, Cork, Ireland.
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Panke S, Held M, Wubbolts MG, Witholt B, Schmid A. Pilot-scale production of (S)-styrene oxide from styrene by recombinant Escherichia coli synthesizing styrene monooxygenase. Biotechnol Bioeng 2002; 80:33-41. [PMID: 12209784 DOI: 10.1002/bit.10346] [Citation(s) in RCA: 132] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recombinant Escherichia coli JM101(pSPZ10) cells produce the styrene monooxygenase of Pseudomonas sp. strain VLB120, which catalyzes the oxidation of styrene to (S)-styrene oxide at an enantiomeric excess larger than 99%. This biocatalyst was used to produce 388 g of styrene oxide in a two-liquid phase 30-L fed-batch bioconversion. The average overall volumetric activity was 170 U per liter over a period of more than 10 h, equivalent to mass transfer rates of 10.2 mmoles per liter per hour at a phase ratio of 0.5. At this transfer rate, the biotransformation system appeared to be substrate mass-transfer limited. The reactor had an estimated power input in the order of 5 W. L(-1), which is close to values typically obtained with commercially operating units. The product could be easily purified by fractional distillation to a purity in excess of 97%. The process illustrates the feasibility of recombinant whole cell biotransformations in two-liquid phase systems with toxic substrates and products.
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Affiliation(s)
- Sven Panke
- Institute of Biotechnology, Swiss Federal Institute of Technology, ETH-Hönggerberg HPT, 8093 Zurich, Switzerland
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Hu S, Gupta P, Prasad AK, Gross RA, Parmar VS. Selective enzymatic epoxidation of dienes: generation of functional enantiomerically enriched diene monoepoxy monomers. Tetrahedron Lett 2002. [DOI: 10.1016/s0040-4039(02)01519-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Bühler B, Witholt B, Hauer B, Schmid A. Characterization and application of xylene monooxygenase for multistep biocatalysis. Appl Environ Microbiol 2002; 68:560-8. [PMID: 11823191 PMCID: PMC126720 DOI: 10.1128/aem.68.2.560-568.2002] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Xylene monooxygenase of Pseudomonas putida mt-2 catalyzes multistep oxidations of one methyl group of toluene and xylenes. Recombinant Escherichia coli expressing the monooxygenase genes xylM and xylA catalyzes the oxygenation of toluene, pseudocumene, the corresponding alcohols, and the corresponding aldehydes, all by a monooxygenation type of reaction (B. Bühler, A. Schmid, B. Hauer, and B. Witholt, J. Biol. Chem. 275:10085-10092, 2000). Using E. coli expressing xylMA, we investigated the kinetics of this one-enzyme three-step biotransformation. We found that unoxidized substrates like toluene and pseudocumene inhibit the second and third oxygenation steps and that the corresponding alcohols inhibit the third oxygenation step. These inhibitions might promote the energetically more favorable alcohol and aldehyde dehydrogenations in the wild type. Growth of E. coli was strongly affected by low concentrations of pseudocumene and its products. Toxicity and solubility problems were overcome by the use of a two-liquid-phase system with bis(2-ethylhexyl)phthalate as the carrier solvent, allowing high overall substrate and product concentrations. In a fed-batch-based two-liquid-phase process with pseudocumene as the substrate, we observed the consecutive accumulation of aldehyde, acid, and alcohol. Our results indicate that, depending on the reaction conditions, product formation could be directed to one specific product.
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Affiliation(s)
- Bruno Bühler
- Institute of Biotechnology, Swiss Federal Institute of Technology Zurich, Hönggerberg HPT, CH-8093 Zurich, Switzerland
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Bühler B, Schmid A, Hauer B, Witholt B. Xylene monooxygenase catalyzes the multistep oxygenation of toluene and pseudocumene to corresponding alcohols, aldehydes, and acids in Escherichia coli JM101. J Biol Chem 2000; 275:10085-92. [PMID: 10744688 DOI: 10.1074/jbc.275.14.10085] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Xylene monooxygenase of Pseudomonas putida mt-2 catalyzes the methylgroup hydroxylation of toluene and xylenes. To investigate the potential of xylene monooxygenase to catalyze multistep oxidations of one methyl group, we tested recombinant Escherichia coli expressing the monooxygenase genes xylM and xylA under the control of the alk regulatory system of Pseudomonas oleovorans Gpo1. Expression of xylene monooxygenase genes could efficiently be controlled by n-octane and dicyclopropylketone. Xylene monooxygenase was found to catalyze the oxygenation of toluene, pseudocumene, the corresponding alcohols, and the corresponding aldehydes. For all three transformations (18)O incorporation provided stong evidence for a monooxygenation type of reaction, with gem-diols as the most likely reaction intermediates during the oxygenation of benzyl alcohols to benzaldehydes. To investigate the role of benzyl alcohol dehydrogenase (XylB) in the formation of benzaldehydes, xylB was cloned behind and expressed in concert with xylMA. In comparison to E. coli expressing only xylMA, the presence of xylB lowered product formation rates and resulted in back formation of benzyl alcohol from benzaldehyde. In P. putida mt-2 XylB may prevent the formation of high concentrations of the particularly reactive benzaldehydes. In the case of high fluxes through the degradation pathways and low aldehyde concentrations, XylB may contribute to benzaldehyde formation via the energetically favorable dehydrogenation of benzyl alcohols. The results presented here characterize XylMA as an enzyme able to catalyze the multistep oxygenation of toluenes.
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Affiliation(s)
- B Bühler
- Institute of Biotechnology, Swiss Federal Institute of Technology Zurich, CH-8093 Zurich, Switzerland
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Panke, Meyer, Huber, Witholt, Wubbolts. An alkane-responsive expression system for the production of fine chemicals. Appl Environ Microbiol 1999; 65:2324-32. [PMID: 10347009 PMCID: PMC91344 DOI: 10.1128/aem.65.6.2324-2332.1999] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/1999] [Accepted: 03/23/1999] [Indexed: 11/20/2022] Open
Abstract
Membrane-located monooxygenase systems, such as the Pseudomonas putida mt-2-derived xylene oxygenase, are attractive for challenging transformations of apolar compounds, including enantiospecific epoxidations, but are difficult to synthesize at levels that are useful for application to biotechnological processes. In order to construct efficient biocatalysis strains, we utilized the alkane-responsive regulatory system of the OCT plasmid-located alk genes of Pseudomonas oleovorans GPo1, a very attractive system for recombinant biotransformation processes. Determination of the nucleotide sequence of alkS, whose activated gene product positively regulates the transcription of the structural genes alkBFGHJKL, on a 3.7-kb SalI-HpaI OCT plasmid fragment was completed, and the N-terminal amino acid sequence of an AlkS-LacZ fusion protein was found to be consistent with the predicted DNA sequence. The alkS gene and the alkBp promoter were assembled into a convenient alkane-responsive genetic expression cassette which allowed expression of the xylene oxygenase genes in a recombinant Escherichia coli strain at a specific activity of 91 U per g (dry weight) of cells when styrene was the substrate. This biocatalyst was used to produce (S)-styrene oxide in two-liquid-phase cultures. Volumetric productivities of more than 2 g of styrene oxide per h per liter of aqueous phase were obtained; these values represented a fivefold improvement compared with previous results.
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Affiliation(s)
- Panke
- Institute of Biotechnology, Swiss Federal Institute of Technology Zurich, CH-8093 Zurich, Switzerland
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Bolognese F, Di Lecce C, Galli E, Barbieri P. Activation and inactivation of Pseudomonas stutzeri methylbenzene catabolism pathways mediated by a transposable element. Appl Environ Microbiol 1999; 65:1876-82. [PMID: 10223973 PMCID: PMC91270 DOI: 10.1128/aem.65.5.1876-1882.1999] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/1998] [Accepted: 02/23/1999] [Indexed: 11/20/2022] Open
Abstract
The arrangement of the genes involved in o-xylene, m-xylene, and p-xylene catabolism was investigated in three Pseudomonas stutzeri strains: the wild-type strain OX1, which is able to grow on o-xylene but not on the meta and para isomers; the mutant M1, which grows on m-xylene and p-xylene but is unable to utilize the ortho isomer; and the revertant R1, which can utilize all the three isomers of xylene. A 3-kb insertion sequence (IS) termed ISPs1, which inactivates the m-xylene and p-xylene catabolic pathway in P. stutzeri OX1 and the o-xylene catabolic genes in P. stutzeri M1, was detected. No IS was detected in the corresponding catabolic regions of the P. stutzeri R1 genome. ISPs1 is present in several copies in the genomes of the three strains. It is flanked by 24-bp imperfect inverted repeats, causes the direct duplication of 8 bp in the target DNA, and seems to be related to the ISL3 family.
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Affiliation(s)
- F Bolognese
- Dipartimento di Genetica e di Biologia dei Microrganismi, Università degli Studi di Milano, 20133 Milan, Italy
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Takami W, Yoshida T, Nojiri H, Yamane H, Omori T. Oxidation of chlorinated olefins by Escherichia coli transformed with dimethyl sulfide monooxygenase genes or cumene dioxygenase genes. J GEN APPL MICROBIOL 1999; 45:69-75. [PMID: 12501390 DOI: 10.2323/jgam.45.69] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
In the present work, it was shown that the dimethyl sulfide (DMS) monooxygenase and the cumene dioxygenase catalyzed oxidation of various chlorinated ethenes, propenes, and butenes. The specific activities of these oxygenases were determined for C(2) to C(4) chlorinated olefins, and the oxidation rates ranged from 0.19 to 4.18 nmol.min(-1).mg(-1) of dry cells by the DMS monooxygenase and from 0.19 to 1.29 nmol.min(-1).mg(-1) of dry cells by the cumene dioxygenase. The oxidation products were identified by gas chromatography-mass spectrometry. Most chlorinated olefins were monooxygenated by the DMS monooxygenase to yield chlorinated epoxides. In the case of the cumene dioxygenase, the substrates lacking any chlorine atom on double-bond carbon atoms were dioxygenated, and those with chlorine atoms attaching to double-bond carbon atoms were monooxygenated to yield allyl alcohols.
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Affiliation(s)
- Wako Takami
- New Energy and Industrial Technology Development Organization (NEDO), Toshima-ku, Tokyo 170-6028, Japan, Asahi Chemical Industry Co., Ltd., Fuji 416-8501, Japan, and Biotechnology Research Center, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
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Schmid A, Sonnleitner B, Witholt B. Medium chain length alkane solvent-cell transfer rates in two-liquid phase, pseudomonas oleovorans cultures. Biotechnol Bioeng 1998; 60:10-23. [PMID: 10099401 DOI: 10.1002/(sici)1097-0290(19981005)60:1<10::aid-bit2>3.0.co;2-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The oxidation of medium chain length alkanes and alkenes (C6 to C12) by Pseudomonas oleovorans and related, biocatalytically active recombinant organisms, in two-liquid phase cultures can be used for the biochemical production of several interesting fine chemicals. The volumetric productivities that can be attained in two-liquid phase systems can be, in contrast to aqueous fermentations, limited by the transport of substrates from an apolar phase to the cells residing in the aqueous phase and by toxic effects of apolar solvents on microbial cells. We have assessed the impact of these possible limitations on attainable productivities in two-liquid phase fermentations operated with mcl-alkanes. Pseudomonas oleovorans grows well in two-liquid phase media containing a bulk n-octane phase as the sole carbon source. However, cells are also damaged, typically resulting in a cell lysis rate of about 0.08 to 0. 10 h-1. These rates could be lowered by 50 to 70% to 0.03 h-1 and substrate yields increased from 0.55 to 0.85 g g-1 by diluting octane in non-metabolizable long-chain hydrocarbon solvents. Transfer rates of medium chain length (mcl) alkanes from the apolar phase to the cells were determined by following growth and the rate at which carbon-containing metabolites accumulated in the different phases of the cultures. mcl-Alkane solvent-cell transfer rates of at least 79, 64, and 18 mmol per liter of aqueous medium per hour were determined for n-heptane, n-octane, and n-decane, respectively. Rates of up to 30 mmol L-1 h-1 were observed under octane-limiting conditions in systems where the apolar substrate was dissolved to concentrations below 3% (v/v) in hexadecene. Based on low power input experiments, we estimated the maximum obtainable mass transfer rates in large scale processes to be in the range of 13 mmol L-1 h-1 for decane and higher than 45 mmol L-1 h-1 for octane and heptane. The results indicate that high solvent to cell mass transfer rates and minimized cell damage will enable high production rates in two-liquid phase bioprocesses, justifying ongoing efforts to attain high densities of catalytically, highly active cells in such systems. Copyright 1998 John Wiley & Sons, Inc.
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Affiliation(s)
- A Schmid
- Institute of Biotechnology, ETH Honggerberg, HPT, CH-8093 Zurich Switzerland
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Panke S, Witholt B, Schmid A, Wubbolts MG. Towards a biocatalyst for (S)-styrene oxide production: characterization of the styrene degradation pathway of Pseudomonas sp. strain VLB120. Appl Environ Microbiol 1998; 64:2032-43. [PMID: 9603811 PMCID: PMC106275 DOI: 10.1128/aem.64.6.2032-2043.1998] [Citation(s) in RCA: 172] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
In order to design a biocatalyst for the production of optically pure styrene oxide, an important building block in organic synthesis, the metabolic pathway and molecular biology of styrene degradation in Pseudomonas sp. strain VLB120 was investigated. A 5.7-kb XhoI fragment, which contained on the same strand of DNA six genes involved in styrene degradation, was isolated from a gene library of this organism in Escherichia coli by screening for indigo formation. T7 RNA polymerase expression experiments indicated that this fragment coded for at least five complete polypeptides, StyRABCD, corresponding to five of the six genes. The first two genes encoded the potential carboxy-terminal part of a sensor, named StySc, and the complete response regulator StyR. Fusion of the putative styAp promoter to a lacZ reporter indicated that StySc and StyR together regulate expression of the structural genes at the transcriptional level. Expression of styScR also alleviated a block that prevented translation of styA mRNA when a heterologous promoter was used. The structural genes styA and styB produced a styrene monooxygenase that converted styrene to styrene oxide, which was then converted to phenylacetaldehyde by StyC. Sequence homology analysis of StyD indicated a probable function as a phenylacetaldehyde dehydrogenase. To assess the usefulness of the enzymes for the production of enantiomerically pure styrene oxide, we investigated the enantiospecificities of the reactions involved. Kinetic resolution of racemic styrene oxide by styrene oxide isomerase was studied with E. coli recombinants carrying styC, which converted styrene oxide at a very high rate but with only a slight preference for the S enantiomer. However, recombinants producing styrene monooxygenase catalyzed the formation of (S)-styrene oxide from inexpensive styrene with an excellent enantiomeric excess of more than 99% at rates up to 180 U g (dry weight) of cells-1.
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Affiliation(s)
- S Panke
- Institute of Biotechnology, Swiss Federal Institute of Technology Zurich, CH-8093 Zurich, Switzerland
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O'Connor KE, Dobson AD, Hartmans S. Indigo formation by microorganisms expressing styrene monooxygenase activity. Appl Environ Microbiol 1997; 63:4287-91. [PMID: 9361415 PMCID: PMC168748 DOI: 10.1128/aem.63.11.4287-4291.1997] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The transformation of indole to indigo by microorganisms expressing styrene monooxygenase (SMO) has been studied. Styrene and indole are structurally very similar, and thus we looked at a variety of styrene-degrading strains for indole transformation to indigo. Two strains, Pseudomonas putida S12 and CA-3, gave a blue color on solid media when grown in the presence of indole. Indole induces its own transformation on solid media but is a poor inducer in liquid media. Styrene is the best inducer of indole transformation in both strains. Arginine represses styrene consumption and indigo formation rates in P. putida S12 compared to phenylacetic acid-grown cells, while the opposite effect is seen for P. putida CA-3. Characterization of an SMO- and styrene oxide isomerase (SOI)-negative transposon mutant of P. putida CA-3 and an SOI-negative N-methyl-N'-nitro-N-nitrosoguanidine mutant of P. putida S12 reveals the involvement of both SMO and SOI in indole transformation to indigo. Both strains stoichiometrically produce high-purity indigo from indole.
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Affiliation(s)
- K E O'Connor
- Department of Food Science, Wageningen Agricultural University, The Netherlands
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Gallagher SC, Cammack R, Dalton H. Alkene monooxygenase from Nocardia corallina B-276 is a member of the class of dinuclear iron proteins capable of stereospecific epoxygenation reactions. EUROPEAN JOURNAL OF BIOCHEMISTRY 1997; 247:635-41. [PMID: 9266707 DOI: 10.1111/j.1432-1033.1997.00635.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Nocardia corallina B-276 possesses a constitutive multi-component alkene monooxygenase which catalyses the epoxidation of terminal and sub-terminal alkenes. The epoxygenase component of this system has been purified with an overall yield of 35%. The electron paramagnetic resonance spectrum of the oxidised protein has a weak signal at g = 4.3, which we ascribe to rhombic iron and a free radical signal at g(ave) = 2.01. Upon partial reduction with dithionite using methyl viologen as a mediator, a signal at g(ave) = 1.9 appeared. Upon further reduction with excess dithionite a signal at g = 15 appeared with the concomitant disappearance of the g(ave) = 1.9 signal. These results indicate that the epoxygenase contains a bridged dinuclear iron centre similar to that found in a variety of proteins involved in oxygen transport and activation as well as desaturation of fatty acids. Analysis of the products of the reaction indicates that AMO is capable of stereospecific epoxidation of alkenes producing the R-enantiomer in high yield, a reaction catalysed by very few oxygenase enzymes. Whole cells gave lower enantiomeric excess values for the epoxide and a stereospecific epoxidase enzyme has been proposed to account for this difference. Although alkene monooxygenase was not inhibited by ethyne, a potent inhibitor of soluble methane monooxygenase with which alkene monooxygenase shares many common features, it was weakly inhibited by propyne with an apparent Km value of 340 microM. The mechanistic implications of these physicochemical features of the enzyme are discussed.
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Affiliation(s)
- S C Gallagher
- Department of Biological Sciences, University of Warwick, Coventry, UK
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Gennaro PD, Galli E, Albini G, Pelizzoni F, Sello G, Bestetti G. Production of substituted naphthalene dihydrodiols by engineered Escherichia coli containing the cloned naphthalene 1,2-dioxygenase gene from Pseudomonas fluorescens N3. Res Microbiol 1997; 148:355-64. [PMID: 9765814 DOI: 10.1016/s0923-2508(97)81591-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Naphthalene dioxygenase, a key enzyme in the dihydroxylation of naphthalene, is encoded by the plasmid pN3, responsible for naphthalene metabolism in Pseudomonas fluorescens N3. The naphthalene dioxygenase, including all the sequences for its expression and the regulatory region, has been localized on the 4.3-kb HindIII-ClaI fragment and on the 3.5-kb HindIII fragment of the plasmid pN3, by Southern analysis using as probes nahA and nahR genes, the homologous genes of the plasmid NAH7 from Pseudomonas putida G7. We cloned in Escherichia coli JM109 the dioxygenase gene and its regulatory region and developed an efficient bacterial system inducible by salicylic acid, able to produce dihydrodiols. E. coli containing recombinant plasmids carrying the dioxygenase gene were analysed for their potential as a biocatalytic tool to produce dihydrodiols from different naphthalenes with the substituent on the aromatic ring at the alpha or beta position. The dihydrodiols, identified by HPLC (high-performance liquid chromatography) and 1H-NMR (nuclear magnetic resonance) were produced with yields ranging from 50 to 94%. The degree of bioconversion efficiency depends on the nature and the position of the substituent and indicates the broad substrate specificity of this dioxygenase and its potential for the production of a wide variety of fine chemicals.
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Affiliation(s)
- P D Gennaro
- Dipartimento di Genetica e Biologia dei Microrganismi, Università degli Studi di Milano, Italy
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Wubbolts M, Hoven J, Melgert B, Witholt B. Efficient production of optically active styrene epoxides in two-liquid phase cultures. Enzyme Microb Technol 1994. [DOI: 10.1016/0141-0229(94)90064-7] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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