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Eggerichs D, Weindorf N, Mascotti ML, Welzel N, Fraaije MW, Tischler D. Vanillyl alcohol oxidase from Diplodia corticola: Residues Ala420 and Glu466 allow for efficient catalysis of syringyl derivatives. J Biol Chem 2023; 299:104898. [PMID: 37295774 PMCID: PMC10404669 DOI: 10.1016/j.jbc.2023.104898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 05/31/2023] [Accepted: 06/05/2023] [Indexed: 06/12/2023] Open
Abstract
Vanillyl alcohol oxidases (VAOs) belong to the 4-phenol oxidases family and are found predominantly in lignin-degrading ascomycetes. Systematical investigation of the enzyme family at the sequence level resulted in discovery and characterization of the second recombinantly produced VAO member, DcVAO, from Diplodia corticola. Remarkably high activities for 2,6-substituted substrates like 4-allyl-2,6-dimethoxy-phenol (3.5 ± 0.02 U mg-1) or 4-(hydroxymethyl)-2,6-dimethoxyphenol (6.3 ± 0.5 U mg-1) were observed, which could be attributed to a Phe to Ala exchange in the catalytic center. In order to rationalize this rare substrate preference among VAOs, we resurrected and characterized three ancestral enzymes and performed mutagenesis analyses. The results indicate that a Cys/Glu exchange was required to retain activity for ɣ-hydroxylations and shifted the acceptance towards benzyl ethers (up to 4.0 ± 0.1 U mg-1). Our findings contribute to the understanding of the functionality of VAO enzyme group, and with DcVAO, we add a new enzyme to the repertoire of ether cleaving biocatalysts.
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Affiliation(s)
- Daniel Eggerichs
- Department of Microbial Biotechnology, Ruhr-University Bochum, Bochum, Germany
| | - Nils Weindorf
- Department of Microbial Biotechnology, Ruhr-University Bochum, Bochum, Germany
| | - Maria Laura Mascotti
- Department of Molecular Enzymology, University of Groningen, Groningen, The Netherlands; Facultad de Química Bioquímica y Farmacia, IMIBIO-SL CONICET, Universidad Nacional de San Luis, San Luis, Argentina
| | - Natalie Welzel
- Department of Microbial Biotechnology, Ruhr-University Bochum, Bochum, Germany
| | - Marco W Fraaije
- Department of Molecular Enzymology, University of Groningen, Groningen, The Netherlands
| | - Dirk Tischler
- Department of Microbial Biotechnology, Ruhr-University Bochum, Bochum, Germany.
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2
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Alvigini L, Gran-Scheuch A, Guo Y, Trajkovic M, Saifuddin M, Fraaije MW, Mattevi A. Discovery, Biocatalytic Exploration and Structural Analysis of a 4-Ethylphenol Oxidase from Gulosibacter chungangensis. Chembiochem 2021; 22:3225-3233. [PMID: 34523783 PMCID: PMC9293466 DOI: 10.1002/cbic.202100457] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 09/14/2021] [Indexed: 11/21/2022]
Abstract
The vanillyl‐alcohol oxidase (VAO) family is a rich source of biocatalysts for the oxidative bioconversion of phenolic compounds. Through genome mining and sequence comparisons, we found that several family members lack a generally conserved catalytic aspartate. This finding led us to study a VAO‐homolog featuring a glutamate residue in place of the common aspartate. This 4‐ethylphenol oxidase from Gulosibacter chungangensis (Gc4EO) shares 42 % sequence identity with VAO from Penicillium simplicissimum, contains the same 8α‐N3‐histidyl‐bound FAD and uses oxygen as electron acceptor. However, Gc4EO features a distinct substrate scope and product specificity as it is primarily effective in the dehydrogenation of para‐substituted phenols with little generation of hydroxylated products. The three‐dimensional structure shows that the characteristic glutamate side chain creates a closely packed environment that may limit water accessibility and thereby protect from hydroxylation. With its high thermal stability, well defined structural properties and high expression yields, Gc4EO may become a catalyst of choice for the specific dehydrogenation of phenolic compounds bearing small substituents.
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Affiliation(s)
- Laura Alvigini
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Via Ferrata 9, 27100, Pavia, Italy
| | - Alejandro Gran-Scheuch
- Molecular Enzymology Group, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Yiming Guo
- Molecular Enzymology Group, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Milos Trajkovic
- Molecular Enzymology Group, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Mohammad Saifuddin
- Molecular Enzymology Group, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Marco W Fraaije
- Molecular Enzymology Group, University of Groningen, Nijenborgh 4, 9747 AG, Groningen, The Netherlands
| | - Andrea Mattevi
- Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Via Ferrata 9, 27100, Pavia, Italy
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3
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Abstract
This review presents a historical outline of the research on vanillyl alcohol oxidase (VAO) from Penicillium simplicissimum, one of the canonical members of the VAO/PCMH flavoprotein family. After describing its discovery and initial biochemical characterization, we discuss the physiological role, substrate scope, and catalytic mechanism of VAO, and review its three-dimensional structure and mechanism of covalent flavinylation. We also explain how protein engineering provided a deeper insight into the role of certain amino acid residues in determining the substrate specificity and enantioselectivity of the enzyme. Finally, we summarize recent computational studies about the migration of substrates and products through the enzyme's structure and the phylogenetic distribution of VAO and related enzymes.
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Affiliation(s)
- Tom A Ewing
- Wageningen Food & Biobased Research, Wageningen University & Research, Wageningen, The Netherlands
| | - Gudrun Gygli
- Institute for Biological Interfaces, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Marco W Fraaije
- Molecular Enzymology Group, University of Groningen, Groningen, The Netherlands
| | - Willem J H van Berkel
- Laboratory of Food Chemistry, Wageningen University & Research, Wageningen, The Netherlands.
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4
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Gupta DK, Rühl M, Mishra B, Kleofas V, Hofrichter M, Herzog R, Pecyna MJ, Sharma R, Kellner H, Hennicke F, Thines M. The genome sequence of the commercially cultivated mushroom Agrocybe aegerita reveals a conserved repertoire of fruiting-related genes and a versatile suite of biopolymer-degrading enzymes. BMC Genomics 2018; 19:48. [PMID: 29334897 PMCID: PMC5769442 DOI: 10.1186/s12864-017-4430-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2017] [Accepted: 12/29/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Agrocybe aegerita is an agaricomycete fungus with typical mushroom features, which is commercially cultivated for its culinary use. In nature, it is a saprotrophic or facultative pathogenic fungus causing a white-rot of hardwood in forests of warm and mild climate. The ease of cultivation and fructification on solidified media as well as its archetypal mushroom fruit body morphology render A. aegerita a well-suited model for investigating mushroom developmental biology. RESULTS Here, the genome of the species is reported and analysed with respect to carbohydrate active genes and genes known to play a role during fruit body formation. In terms of fruit body development, our analyses revealed a conserved repertoire of fruiting-related genes, which corresponds well to the archetypal fruit body morphology of this mushroom. For some genes involved in fruit body formation, paralogisation was observed, but not all fruit body maturation-associated genes known from other agaricomycetes seem to be conserved in the genome sequence of A. aegerita. In terms of lytic enzymes, our analyses suggest a versatile arsenal of biopolymer-degrading enzymes that likely account for the flexible life style of this species. Regarding the amount of genes encoding CAZymes relevant for lignin degradation, A. aegerita shows more similarity to white-rot fungi than to litter decomposers, including 18 genes coding for unspecific peroxygenases and three dye-decolourising peroxidase genes expanding its lignocellulolytic machinery. CONCLUSIONS The genome resource will be useful for developing strategies towards genetic manipulation of A. aegerita, which will subsequently allow functional genetics approaches to elucidate fundamentals of fruiting and vegetative growth including lignocellulolysis.
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Affiliation(s)
- Deepak K Gupta
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Frankfurt a. M., Germany.,Institute of Ecology, Evolution and Diversity, Goethe University Frankfurt, Frankfurt a. M., Germany.,LOEWE Cluster of Integrative Fungal Research (IPF), Frankfurt a. M., Germany
| | - Martin Rühl
- Institute of Food Chemistry and Food Biotechnology, Justus Liebig University Giessen, Giessen, Germany.,LOEWE Cluster of Integrative Fungal Research (IPF), Frankfurt a. M., Germany.,Project Group "Bioresources", Fraunhofer IME, Giessen, Germany
| | - Bagdevi Mishra
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Frankfurt a. M., Germany.,Institute of Ecology, Evolution and Diversity, Goethe University Frankfurt, Frankfurt a. M., Germany.,LOEWE Cluster of Integrative Fungal Research (IPF), Frankfurt a. M., Germany
| | - Vanessa Kleofas
- Institute of Food Chemistry and Food Biotechnology, Justus Liebig University Giessen, Giessen, Germany.,LOEWE Cluster of Integrative Fungal Research (IPF), Frankfurt a. M., Germany
| | - Martin Hofrichter
- International Institute (IHI) Zittau, Technische Universität Dresden, Zittau, Germany
| | - Robert Herzog
- Junior Research Group Genetics and Genomics of Fungi, Senckenberg Gesellschaft für Naturforschung, Frankfurt a. M., Germany.,Institute of Ecology, Evolution and Diversity, Goethe University Frankfurt, Frankfurt a. M., Germany.,LOEWE Cluster of Integrative Fungal Research (IPF), Frankfurt a. M., Germany
| | - Marek J Pecyna
- University of Applied Sciences Zittau/Görlitz, Zittau, Germany
| | - Rahul Sharma
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Frankfurt a. M., Germany.,Institute of Ecology, Evolution and Diversity, Goethe University Frankfurt, Frankfurt a. M., Germany.,LOEWE Cluster of Integrative Fungal Research (IPF), Frankfurt a. M., Germany
| | - Harald Kellner
- International Institute (IHI) Zittau, Technische Universität Dresden, Zittau, Germany
| | - Florian Hennicke
- Junior Research Group Genetics and Genomics of Fungi, Senckenberg Gesellschaft für Naturforschung, Frankfurt a. M., Germany. .,Institute of Ecology, Evolution and Diversity, Goethe University Frankfurt, Frankfurt a. M., Germany. .,LOEWE Cluster of Integrative Fungal Research (IPF), Frankfurt a. M., Germany. .,Department of Biology, Microbiology, Utrecht University, Utrecht, The Netherlands.
| | - Marco Thines
- Senckenberg Biodiversity and Climate Research Centre (BiK-F), Frankfurt a. M., Germany. .,Institute of Ecology, Evolution and Diversity, Goethe University Frankfurt, Frankfurt a. M., Germany. .,LOEWE Cluster of Integrative Fungal Research (IPF), Frankfurt a. M., Germany.
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5
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Ewing TA, Gygli G, van Berkel WJH. A single loop is essential for the octamerization of vanillyl alcohol oxidase. FEBS J 2016; 283:2546-59. [PMID: 27214042 DOI: 10.1111/febs.13762] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 05/20/2016] [Indexed: 11/30/2022]
Abstract
UNLABELLED The VAO/PCMH family of flavoenzymes is a family of structurally related proteins that catalyse a wide range of oxidation reactions. It contains a subfamily of enzymes that catalyse the oxidation of para-substituted phenols using covalently bound FAD cofactors (the 4PO subfamily). This subfamily is composed of two oxidases, vanillyl alcohol oxidase (VAO) and eugenol oxidase (EUGO), and two flavocytochrome dehydrogenases, para-cresol methylhydroxylase (PCMH) and eugenol hydroxylase (EUGH). Although they catalyse similar reactions, these enzymes differ in terms of their electron acceptor preference and oligomerization state. For example, VAO forms homo-octamers that can be described as tetramers of stable dimers, whereas EUGO is exclusively dimeric in solution. A possible explanation for this difference is the presence of a loop at the dimer-dimer interface in VAO that is not present in EUGO. Here, the role played by this loop in determining the quaternary structure of these enzymes is investigated. A VAO variant where the loop was deleted, loopless VAO, exclusively formed dimers. However, introduction of the loop into EUGO was not sufficient to induce its octamerization. Neither variant displayed major changes in its catalytic properties as compared to the wild-type enzyme. Bioinformatic analysis revealed that the presence of the loop is conserved within putative fungal oxidases of the 4PO subgroup, but it is never found in putative bacterial oxidases or dehydrogenases. Our results shed light on the molecular mechanism of homo-oligomerization of VAO and the importance of oligomerization for its enzymatic function. ENZYMES p-cresol methylhydroxylase (4-methylphenol:acceptor oxidoreductase (methyl-hydroxylating), EC 1.17.99.1); vanillyl alcohol oxidase (vanillyl alcohol:oxygen oxidoreductase, EC 1.1.3.38).
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Affiliation(s)
- Tom A Ewing
- Laboratory of Biochemistry, Wageningen University, The Netherlands
| | - Gudrun Gygli
- Laboratory of Biochemistry, Wageningen University, The Netherlands
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6
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Aboobucker SI, Lorence A. Recent progress on the characterization of aldonolactone oxidoreductases. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2016; 98:171-85. [PMID: 26696130 PMCID: PMC4725720 DOI: 10.1016/j.plaphy.2015.11.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Revised: 11/23/2015] [Accepted: 11/24/2015] [Indexed: 06/05/2023]
Abstract
L-Ascorbic acid (ascorbate, AsA, vitamin C) is essential for animal and plant health. Despite our dependence on fruits and vegetables to fulfill our requirement for this vitamin, the metabolic network leading to its formation in plants is just being fully elucidated. There is evidence supporting the operation of at least four biosynthetic pathways leading to AsA formation in plants. These routes use D-mannose/L-galactose, L-gulose, D-galacturonate, and myo-inositol as the main precursors. This review focuses on aldonolactone oxidoreductases, a subgroup of the vanillyl alcohol oxidase (VAO; EC 1.1.3.38) superfamily, enzymes that catalyze the terminal step in AsA biosynthesis in bacteria, protozoa, animals, and plants. In this report, we review the properties of well characterized aldonolactone oxidoreductases to date. A shared feature in these proteins is the presence of a flavin cofactor as well as a thiol group. The flavin cofactor in many cases is bound to the N terminus of the enzymes or to a recently discovered HWXK motif in the C terminus. The binding between the flavin moiety and the protein can be either covalent or non-covalent. Substrate specificity and subcellular localization differ among the isozymes of each kingdom. All oxidases among these enzymes possess dehydrogenase activity, however, exclusive dehydrogenases are also found. We also discuss recent evidence indicating that plants have both L-gulono-1,4-lactone oxidases and L-galactono-1,4-lactone dehydrogenases involved in AsA biosynthesis.
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Affiliation(s)
- Siddique I Aboobucker
- Arkansas Biosciences Institute, Arkansas State University, P.O. Box 639, State University, AR 72467, USA
| | - Argelia Lorence
- Arkansas Biosciences Institute, Arkansas State University, P.O. Box 639, State University, AR 72467, USA; Department of Chemistry and Physics, Arkansas State University, P.O. Box 419, State University, AR 72467, USA.
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7
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Mäkelä MR, Marinović M, Nousiainen P, Liwanag AJM, Benoit I, Sipilä J, Hatakka A, de Vries RP, Hildén KS. Aromatic metabolism of filamentous fungi in relation to the presence of aromatic compounds in plant biomass. ADVANCES IN APPLIED MICROBIOLOGY 2015; 91:63-137. [PMID: 25911233 DOI: 10.1016/bs.aambs.2014.12.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The biological conversion of plant lignocellulose plays an essential role not only in carbon cycling in terrestrial ecosystems but also is an important part of the production of second generation biofuels and biochemicals. The presence of the recalcitrant aromatic polymer lignin is one of the major obstacles in the biofuel/biochemical production process and therefore microbial degradation of lignin is receiving a great deal of attention. Fungi are the main degraders of plant biomass, and in particular the basidiomycete white rot fungi are of major importance in converting plant aromatics due to their ability to degrade lignin. However, the aromatic monomers that are released from lignin and other aromatic compounds of plant biomass are toxic for most fungi already at low levels, and therefore conversion of these compounds to less toxic metabolites is essential for fungi. Although the release of aromatic compounds from plant biomass by fungi has been studied extensively, relatively little attention has been given to the metabolic pathways that convert the resulting aromatic monomers. In this review we provide an overview of the aromatic components of plant biomass, and their release and conversion by fungi. Finally, we will summarize the applications of fungal systems related to plant aromatics.
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Affiliation(s)
- Miia R Mäkelä
- Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Mila Marinović
- Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Paula Nousiainen
- Department of Chemistry, Laboratory of Organic Chemistry, University of Helsinki, Helsinki, Finland
| | - April J M Liwanag
- Fungal Physiology, CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands; Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - Isabelle Benoit
- Fungal Physiology, CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands; Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - Jussi Sipilä
- Department of Chemistry, Laboratory of Organic Chemistry, University of Helsinki, Helsinki, Finland
| | - Annele Hatakka
- Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Ronald P de Vries
- Fungal Physiology, CBS-KNAW Fungal Biodiversity Centre, Utrecht, The Netherlands; Fungal Molecular Physiology, Utrecht University, Utrecht, The Netherlands
| | - Kristiina S Hildén
- Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland
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Gallage NJ, Møller BL. Vanillin-bioconversion and bioengineering of the most popular plant flavor and its de novo biosynthesis in the vanilla orchid. MOLECULAR PLANT 2015; 8:40-57. [PMID: 25578271 DOI: 10.1016/j.molp.2014.11.008] [Citation(s) in RCA: 141] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 09/15/2014] [Indexed: 05/24/2023]
Abstract
In recent years, biotechnology-derived production of flavors and fragrances has expanded rapidly. The world's most popular flavor, vanillin, is no exception. This review outlines the current state of biotechnology-based vanillin synthesis with the use of ferulic acid, eugenol, and glucose as substrates and bacteria, fungi, and yeasts as microbial production hosts. The de novo biosynthetic pathway of vanillin in the vanilla orchid and the possible applied uses of this new knowledge in the biotechnology-derived and pod-based vanillin industries are also highlighted.
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Affiliation(s)
- Nethaji J Gallage
- VILLUM Research Center for Plant Plasticity, Department of Plant and Environmental Sciences, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark; Center for Synthetic Biology "bioSYNergy", Department of Plant and Environmental Sciences, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark; Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark
| | - Birger Lindberg Møller
- VILLUM Research Center for Plant Plasticity, Department of Plant and Environmental Sciences, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark; Center for Synthetic Biology "bioSYNergy", Department of Plant and Environmental Sciences, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark; Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, 40 Thorvaldsensvej, DK-1871 Frederiksberg C, Copenhagen, Denmark; Carlsberg Laboratory, 10 Gamle Carlsberg Vej, DK-1799 Copenhagen V, Denmark.
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9
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Chakraborty M, Goel M, Chinnadayyala SR, Dahiya UR, Ghosh SS, Goswami P. Molecular characterization and expression of a novel alcohol oxidase from Aspergillus terreus MTCC6324. PLoS One 2014; 9:e95368. [PMID: 24752075 PMCID: PMC3994049 DOI: 10.1371/journal.pone.0095368] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 03/26/2014] [Indexed: 11/28/2022] Open
Abstract
The alcohol oxidase (AOx) cDNA from Aspergillus terreus MTCC6324 with an open reading frame (ORF) of 2001 bp was constructed from n-hexadecane induced cells and expressed in Escherichia coli with a yield of ∼4.2 mg protein g−1 wet cell. The deduced amino acid sequences of recombinant rAOx showed maximum structural homology with the chain B of aryl AOx from Pleurotus eryngii. A functionally active AOx was achieved by incubating the apo-AOx with flavin adenine dinucleotide (FAD) for ∼80 h at 16°C and pH 9.0. The isoelectric point and mass of the apo-AOx were found to be 6.5±0.1 and ∼74 kDa, respectively. Circular dichroism data of the rAOx confirmed its ordered structure. Docking studies with an ab-initio protein model demonstrated the presence of a conserved FAD binding domain with an active substrate binding site. The rAOx was specific for aryl alcohols and the order of its substrate preference was 4-methoxybenzyl alcohol >3-methoxybenzyl alcohol>3, 4-dimethoxybenzyl alcohol > benzyl alcohol. A significantly high aggregation to ∼1000 nm (diameter) and catalytic efficiency (kcat/Km) of 7829.5 min−1 mM−1 for 4-methoxybenzyl alcohol was also demonstrated for rAOx. The results infer the novelty of the AOx and its potential biocatalytic application.
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Affiliation(s)
- Mitun Chakraborty
- Department of Biotechnology, Indian Institute of Technology Guwahati, Assam, India
| | - Manish Goel
- Department of Biotechnology, Indian Institute of Technology Guwahati, Assam, India
| | | | - Ujjwal Ranjan Dahiya
- Department of Biotechnology, Indian Institute of Technology Guwahati, Assam, India
| | - Siddhartha Sankar Ghosh
- Department of Biotechnology, Indian Institute of Technology Guwahati, Assam, India
- * E-mail: (SSG); (PG)
| | - Pranab Goswami
- Department of Biotechnology, Indian Institute of Technology Guwahati, Assam, India
- * E-mail: (SSG); (PG)
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10
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Lambert F, Zucca J, Ness F, Aigle M. Production of ferulic acid and coniferyl alcohol by conversion of eugenol using a recombinant strain ofSaccharomyces cerevisiae. FLAVOUR FRAG J 2013. [DOI: 10.1002/ffj.3173] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Fanny Lambert
- V. Mane Fils; 620 route de Grasse 06620 Le Bar sur Loup France
| | - Joseph Zucca
- V. Mane Fils; 620 route de Grasse 06620 Le Bar sur Loup France
| | - Frédérique Ness
- Institut de Biochimie et de Génétique Cellulaires, Unité Mixte de Recherche 5095; Centre National de la Recherche Scientifique et Université Victor Segalen Bordeaux 2; 1 rue Camille Saint Saëns 33077 Bordeaux cedex France
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11
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Kasahara K, Miyamoto T, Fujimoto T, Oguri H, Tokiwano T, Oikawa H, Ebizuka Y, Fujii I. Solanapyrone Synthase, a Possible Diels-Alderase and Iterative Type I Polyketide Synthase Encoded in a Biosynthetic Gene Cluster from Alternaria solani. Chembiochem 2010; 11:1245-52. [DOI: 10.1002/cbic.201000173] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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12
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Kuratani M, Tanaka K, Terashima K, Muraguchi H, Nakazawa T, Nakahori K, Kamada T. The dst2 gene essential for photomorphogenesis of Coprinopsis cinerea encodes a protein with a putative FAD-binding-4 domain. Fungal Genet Biol 2009; 47:152-8. [PMID: 19850145 DOI: 10.1016/j.fgb.2009.10.006] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Revised: 10/13/2009] [Accepted: 10/13/2009] [Indexed: 01/20/2023]
Abstract
The fruiting-body primordium of Coprinopsis cinerea exhibits remarkable photomorphogenesis. Under a 12-h light/12-h dark regime, the primordium proceeds to the fruiting-body maturation phase in which the primordium successively undergoes basidiospore formation, stipe elongation and pileus expansion, resulting in the mature fruiting-body. In continuous darkness, however, the primordium never proceeds to the maturation phase: the pileus and stipe tissues at the upper part of the primordium remain rudimentary while the basal part of the primordium elongates, producing the etiolated "dark stipe" phenotype. In our previous studies, blind mutants, which produce dark stipes under light conditions that promote fruiting-body maturation in the wild-type, have been isolated, and two genes, dst1 and dst2, responsible for the mutant phenotype have been identified. In this study we show that the dst2-1 mutant exhibits a blind phenotype during asexual spore production in addition to that in fruiting-body photomorphogenesis. We also reveal that dst2 is predicted to encode a protein with a putative flavin adenine dinucleotide (FAD)-binding-4 domain. The two blind phenotypes, together with the existence of an FAD-binding domain in Dst2, suggest that Dst2 may play a role in perceiving blue light.
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Affiliation(s)
- Masaki Kuratani
- Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
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13
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Jin J, Mazon H, van den Heuvel RHH, Heck AJ, Janssen DB, Fraaije MW. Covalent flavinylation of vanillyl-alcohol oxidase is an autocatalytic process. FEBS J 2008; 275:5191-200. [PMID: 18793324 DOI: 10.1111/j.1742-4658.2008.06649.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Vanillyl-alcohol oxidase (VAO; EC 1.1.3.38) contains a covalently 8alpha-histidyl bound FAD, which represents the most frequently encountered covalent flavin-protein linkage. To elucidate the mechanism by which VAO covalently incorporates the FAD cofactor, apo VAO was produced by using a riboflavin auxotrophic Escherichia coli strain. Incubation of apo VAO with FAD resulted in full restoration of enzyme activity. The rate of activity restoration was dependent on FAD concentration, displaying a hyperbolic relationship (K(FAD )= 2.3 microM, k(activation) = 0.13 min(-1)). The time-dependent increase in enzyme activity was accompanied by full covalent incorporation of FAD, as determined by SDS/PAGE and ESI-MS analysis. The results obtained show that formation of the covalent flavin-protein bond is an autocatalytic process, which proceeds via a reduced flavin intermediate. Furthermore, ESI-MS experiments revealed that, although apo VAO mainly exists as monomers and dimers, FAD binding promotes the formation of VAO dimers and octamers. Tandem ESI-MS experiments revealed that octamerization is not dependent on full covalent flavinylation.
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Affiliation(s)
- Jianfeng Jin
- Laboratory of Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, The Netherlands
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14
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Jin J, Mazon H, van den Heuvel RHH, Janssen DB, Fraaije MW. Discovery of a eugenol oxidase from Rhodococcus sp. strain RHA1. FEBS J 2007; 274:2311-21. [PMID: 17419730 DOI: 10.1111/j.1742-4658.2007.05767.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A gene encoding a eugenol oxidase was identified in the genome from Rhodococcus sp. strain RHA1. The bacterial FAD-containing oxidase shares 45% amino acid sequence identity with vanillyl alcohol oxidase from the fungus Penicillium simplicissimum. Eugenol oxidase could be expressed at high levels in Escherichia coli, which allowed purification of 160 mg of eugenol oxidase from 1 L of culture. Gel permeation experiments and macromolecular MS revealed that the enzyme forms homodimers. Eugenol oxidase is partly expressed in the apo form, but can be fully flavinylated by the addition of FAD. Cofactor incorporation involves the formation of a covalent protein-FAD linkage, which is formed autocatalytically. Modeling using the vanillyl alcohol oxidase structure indicates that the FAD cofactor is tethered to His390 in eugenol oxidase. The model also provides a structural explanation for the observation that eugenol oxidase is dimeric whereas vanillyl alcohol oxidase is octameric. The bacterial oxidase efficiently oxidizes eugenol into coniferyl alcohol (KM=1.0 microM, kcat=3.1 s-1). Vanillyl alcohol and 5-indanol are also readily accepted as substrates, whereas other phenolic compounds (vanillylamine, 4-ethylguaiacol) are converted with relatively poor catalytic efficiencies. The catalytic efficiencies with the identified substrates are strikingly different when compared with vanillyl alcohol oxidase. The ability to efficiently convert eugenol may facilitate biotechnological valorization of this natural aromatic compound.
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Affiliation(s)
- Jianfeng Jin
- Laboratory of Biochemistry, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, The Netherlands
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15
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Overhage J, Steinbüchel A, Priefert H. Harnessing eugenol as a substrate for production of aromatic compounds with recombinant strains of Amycolatopsis sp. HR167. J Biotechnol 2006; 125:369-76. [PMID: 16677732 DOI: 10.1016/j.jbiotec.2006.03.024] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2005] [Revised: 11/14/2005] [Accepted: 03/06/2006] [Indexed: 10/24/2022]
Abstract
To harness eugenol as cheap substrate for the biotechnological production of aromatic compounds, the vanillyl alcohol oxidase gene (vaoA) from Penicillium simplicissimum CBS 170.90 was cloned in an expression vector suitable for Gram-positive bacteria and expressed in the vanillin-tolerant Gram-positive strain Amycolatopsis sp. HR167. Recombinant strains harboring hybrid plasmid pRLE6SKvaom exhibited a specific vanillyl alcohol oxidase activity of 1.1U/g protein. Moreover, this strain had gained the ability to grow on eugenol as sole carbon source. The intermediates coniferyl alcohol, coniferyl aldehyde, ferulic acid, guajacol, and vanillic acid were detected as excreted compounds during growth on eugenol, whereas vanillin could only be detected in trace amounts. Resting cells of Amycolatopsis sp. HR167 (pRLE6SKvaom) produced coniferyl alcohol from eugenol with a maximum conversion rate of about 2.3 mmol/h/l of culture, and a maximum coniferyl alcohol concentration of 4.7 g/1 was obtained after 16 h biotransformation without further optimization. Beside coniferyl alcohol, traces of coniferyl aldehyde and ferulic acid were also detected.
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Affiliation(s)
- Jörg Overhage
- Institut für Molekulare Mikrobiologie und Biotechnologie der Westfälischen Wilhelms-Universität Munster, Corrensstrasse 3, D-48149 Münster, Germany
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16
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Zeng GM, Yu HY, Huang HL, Huang DL, Chen YN, Huang GH, Li JB. Laccase activities of a soil fungus Penicillium simplicissimum in relation to lignin degradation. World J Microbiol Biotechnol 2006. [DOI: 10.1007/s11274-005-9025-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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van den Heuvel RHH, van den Berg WAM, Rovida S, van Berkel WJH. Laboratory-evolved vanillyl-alcohol oxidase produces natural vanillin. J Biol Chem 2004; 279:33492-500. [PMID: 15169773 DOI: 10.1074/jbc.m312968200] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The flavoenzyme vanillyl-alcohol oxidase was subjected to random mutagenesis to generate mutants with enhanced reactivity to creosol (2-methoxy-4-methylphenol). The vanillyl-alcohol oxidase-mediated conversion of creosol proceeds via a two-step process in which the initially formed vanillyl alcohol (4-hydroxy-3-methoxybenzyl alcohol) is oxidized to the widely used flavor compound vanillin (4-hydroxy-3-methoxybenzaldehyde). The first step of this reaction is extremely slow due to the formation of a covalent FAD N-5-creosol adduct. After a single round of error-prone PCR, seven mutants were generated with increased reactivity to creosol. The single-point mutants I238T, F454Y, E502G, and T505S showed an up to 40-fold increase in catalytic efficiency (kcat/Km) with creosol compared with the wild-type enzyme. This enhanced reactivity was due to a lower stability of the covalent flavin-substrate adduct, thereby promoting vanillin formation. The catalytic efficiencies of the mutants were also enhanced for other ortho-substituted 4-methylphenols, but not for p-cresol (4-methylphenol). The replaced amino acid residues are not located within a distance of direct interaction with the substrate, and the determined three-dimensional structures of the mutant enzymes are highly similar to that of the wild-type enzyme. These results clearly show the importance of remote residues, not readily predicted by rational design, for the substrate specificity of enzymes.
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Affiliation(s)
- Robert H H van den Heuvel
- Department of Genetics and Microbiology, University of Pavia, via Abbiategrasso 207, 27100 Pavia, Italy
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18
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Overhage J, Steinbüchel A, Priefert H. Highly efficient biotransformation of eugenol to ferulic acid and further conversion to vanillin in recombinant strains of Escherichia coli. Appl Environ Microbiol 2004; 69:6569-76. [PMID: 14602615 PMCID: PMC262297 DOI: 10.1128/aem.69.11.6569-6576.2003] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The vaoA gene from Penicillium simplicissimum CBS 170.90, encoding vanillyl alcohol oxidase, which also catalyzes the conversion of eugenol to coniferyl alcohol, was expressed in Escherichia coli XL1-Blue under the control of the lac promoter, together with the genes calA and calB, encoding coniferyl alcohol dehydrogenase and coniferyl aldehyde dehydrogenase of Pseudomonas sp. strain HR199, respectively. Resting cells of the corresponding recombinant strain E. coli XL1-Blue(pSKvaomPcalAmcalB) converted eugenol to ferulic acid with a molar yield of 91% within 15 h on a 50-ml scale, reaching a ferulic acid concentration of 8.6 g liter(-1). This biotransformation was scaled up to a 30-liter fermentation volume. The maximum production rate for ferulic acid at that scale was 14.4 mmol per h per liter of culture. The maximum concentration of ferulic acid obtained was 14.7 g liter(-1) after a total fermentation time of 30 h, which corresponded to a molar yield of 93.3% with respect to the added amount of eugenol. In a two-step biotransformation, E. coli XL1-Blue(pSKvaomPcalAmcalB) was used to produce ferulic acid from eugenol and, subsequently, E. coli(pSKechE/Hfcs) was used to convert ferulic acid to vanillin (J. Overhage, H. Priefert, and A. Steinbüchel, Appl. Environ. Microbiol. 65:4837-4847, 1999). This process led to 0.3 g of vanillin liter(-1), besides 0.1 g of vanillyl alcohol and 4.6 g of ferulic acid liter(-1). The genes ehyAB, encoding eugenol hydroxylase of Pseudomonas sp. strain HR199, and azu, encoding the potential physiological electron acceptor of this enzyme, were shown to be unsuitable for establishing eugenol bioconversion in E. coli XL1-Blue.
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Affiliation(s)
- Jörg Overhage
- Institut für Molekulare Mikrobiologie und Biotechnologie der Westfälischen Wilhelms-Universität Münster, D-48149 Münster, Germany
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19
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20
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Tahallah N, Van Den Heuvel RHH, Van Den Berg WAM, Maier CS, Van Berkel WJH, Heck AJR. Cofactor-dependent assembly of the flavoenzyme vanillyl-alcohol oxidase. J Biol Chem 2002; 277:36425-32. [PMID: 12107187 DOI: 10.1074/jbc.m205841200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The oligomerization of the flavoprotein vanillyl-alcohol oxidase (VAO) and its site-directed mutant H61T was studied by mass spectrometry. Native VAO has a covalently bound FAD and forms primarily octameric assemblies of 507 kDa. H61T is purified as a FAD-free apoprotein and mainly exists as a dimeric species of 126 kDa. Binding of FAD to apoH61T rapidly restores enzyme activity and induces octamerization, although association of H61T dimers seems not to be crucial for enzyme activity. Reconstitution of H61T with the cofactor analog 5'-ADP also promotes octamerization. FMN on the other hand, interacts with apoH61T without stimulating dimer association. These results are in line with observations made for several other flavoenzymes, which contain a Rossmann fold. Members of the VAO flavoprotein family do not contain a Rossmann fold but do share two conserved loops that are responsible for binding the pyrophosphate moiety of FAD. Therefore, the observed FAD-induced oligomerization might be general for this family. We speculate that upon FAD binding, small conformational changes in the ADP-binding pocket of the dimeric VAO species are transmitted to the protein surface, promoting oligomerization.
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Affiliation(s)
- Nora Tahallah
- Department of Biomolecular Mass Spectrometry, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands
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21
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van den Heuvel RH, Partridge J, Laane C, Halling PJ, van Berkel WJ. Tuning of the product spectrum of vanillyl-alcohol oxidase by medium engineering. FEBS Lett 2001; 503:213-6. [PMID: 11513884 DOI: 10.1016/s0014-5793(01)02658-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The flavoenzyme vanillyl-alcohol oxidase (VAO) catalyzes the conversion of 4-alkylphenols through the initial formation of p-quinone methide intermediates. These electrophilic species are stereospecifically attacked by water to yield (R)-1-(4'-hydroxyphenyl)alcohols or rearranged in a competing reaction to 1-(4'-hydroxyphenyl)alkenes. Here, we show that the product spectrum of VAO can be controlled by medium engineering. When the enzymatic conversion of 4-propylphenol was performed in organic solvent, the concentration of the alcohol decreased and the concentration of the cis-alkene, but not the trans-alkene, increased. This change in selectivity occurred in both toluene and acetonitrile and was dependent on the water activity of the reaction medium. A similar shift in alcohol/cis-alkene product ratio was observed when the VAO-mediated conversion of 4-propylphenol was performed in the presence of monovalent anions that bind specifically near the enzyme active site.
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Affiliation(s)
- R H van den Heuvel
- Department of Agrotechnology and Food Sciences, Wageningen University, The Netherlands
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22
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Tuthill DE, Frisvad JC, Christensen M. Systematics of Penicillium simplicissimum based on rDNA sequences, morphology and secondary metabolites. Mycologia 2001. [DOI: 10.1080/00275514.2001.12063161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
| | - Jens C. Frisvad
- Department of Biotechnology, Technical University of Denmark, DK-2800 Lyngby, Denmark
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23
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Tahallah N, Pinkse M, Maier CS, Heck AJ. The effect of the source pressure on the abundance of ions of noncovalent protein assemblies in an electrospray ionization orthogonal time-of-flight instrument. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2001; 15:596-601. [PMID: 11312509 DOI: 10.1002/rcm.275] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The effect of elevating the pressure in the interface region of an electrospray ionization orthogonal time-of-flight mass spectrometer on the ion intensity of different noncovalent protein assemblies has been investigated. Elevating the pressure in the interface region generally led to an enhanced detection of high m/z ions. The optimum pressure was found to be dependent on the m/z value of the ions. This pressure effect should be carefully addressed when relating ion abundance in the mass spectra to solution phase abundance of noncovalent protein assemblies.
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Affiliation(s)
- N Tahallah
- Department of Biomolecular Mass Spectrometry, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands
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24
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25
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Abstract
Microorganisms able to produce vanillin in excess of 6g/l from ferulic acid have now been isolated. In Pseudomonas strains, the metabolic pathway from eugenol via ferulic acid to vanillin has been characterised at the enzymic and molecular genetic levels. Attempts to introduce vanillin production into other organisms by genetic engineering have begun.
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Affiliation(s)
- N J Walton
- Food Safety Science Division, Institute of Food Research, Norwich Research Park, Colney, NR4 7UA, Norwich, UK.
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26
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van den Heuvel RH, Fraaije MW, van Berkel WJ. Direction of the reactivity of vanillyl-alcohol oxidase with 4-alkylphenols. FEBS Lett 2000; 481:109-12. [PMID: 10996306 DOI: 10.1016/s0014-5793(00)01992-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The covalent flavoprotein vanillyl-alcohol oxidase (VAO) predominantly converts short-chain 4-alkylphenols, like 4-ethylphenol, to (R)-1-(4'-hydroxyphenyl)alcohols and medium-chain 4-alkylphenols, like 4-butylphenol, to 1-(4'-hydroxyphenyl)alkenes. Crystallographic studies have indicated that the active site residue Asp170 is involved in determining the efficiency of substrate hydroxylation. To test this hypothesis, we have addressed the reactivity of Asp170 variants with 4-alkylphenols. The substrate preference of Asp170Glu was similar to wild type VAO. However, Asp170Ser was most active with branched-chain 4-alkylphenols. The hydroxylation efficiency of the Asp170 variants was dependent on the bulkiness of the newly introduced side chain. The Glu170 mutation favored the production of alkenes, whereas the Ser170 mutation stimulated the formation of alcohols.
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Affiliation(s)
- R H van den Heuvel
- Laboratory of Biochemistry, Department of Biomolecular Sciences, Wageningen University, Dreijenlaan 3, 6703 HA Wageningen, The Netherlands
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27
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van Den Heuvel RH, Fraaije MW, Ferrer M, Mattevi A, van Berkel WJ. Inversion of stereospecificity of vanillyl-alcohol oxidase. Proc Natl Acad Sci U S A 2000; 97:9455-60. [PMID: 10920192 PMCID: PMC16885 DOI: 10.1073/pnas.160175897] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Vanillyl-alcohol oxidase (VAO) is the prototype of a newly recognized family of structurally related oxidoreductases sharing a conserved FAD-binding domain. The active site of VAO is formed by a cavity where the enzyme is able to catalyze many reactions with phenolic substrates. Among these reactions is the stereospecific hydroxylation of 4-ethylphenol-forming (R)-1-(4'-hydroxyphenyl)ethanol. During this conversion, Asp-170 is probably critical for the hydration of the initially formed p-quinone methide intermediate. By site-directed mutagenesis, the putative active site base has been relocated to the opposite face of the active site cavity. In this way, a change in stereospecificity has been achieved. Like native VAO, the single mutants T457E, D170A, and D170S preferentially converted 4-ethylphenol to the (R)-enantiomer of 1-(4'-hydroxyphenyl)ethanol. The double mutants D170A/T457E and D170S/T457E exhibited an inverted stereospecificity with 4-ethylphenol. Particularly, D170S/T457E was strongly (S)-selective, with an enantiomeric excess of 80%. The crystal structure of D170S/T457E, in complex with trifluoromethylphenol, showed a highly conserved mode of ligand binding and revealed that the distinctive catalytic properties of this mutant are not caused by major structural changes.
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Affiliation(s)
- R H van Den Heuvel
- Department of Biomolecular Sciences, Laboratory of Biochemistry, Wageningen University, The Netherlands
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28
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van den Heuvel RH, Fraaije MW, Mattevi A, van Berkel WJ. Asp-170 is crucial for the redox properties of vanillyl-alcohol oxidase. J Biol Chem 2000; 275:14799-808. [PMID: 10809721 DOI: 10.1074/jbc.275.20.14799] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Vanillyl-alcohol oxidase is a flavoprotein containing a covalent flavin that catalyzes the oxidation of 4-(methoxymethyl)phenol to 4-hydroxybenzaldehyde. The reaction proceeds through the formation of a p-quinone methide intermediate, after which, water addition takes place. Asp-170, located near the N5-atom of the flavin, has been proposed to act as an active site base. To test this hypothesis, we have addressed the properties of D170E, D170S, D170A, and D170N variants. Spectral and fluorescence analysis, together with the crystal structure of D170S, suggests that the Asp-170 replacements do not induce major structural changes. However, in D170A and D170N, 50 and 100%, respectively, of the flavin is non-covalently bound. Kinetic characterization of the vanillyl-alcohol oxidase variants revealed that Asp-170 is required for catalysis. D170E is 50-fold less active, and the other Asp-170 variants are about 10(3)-fold less active than wild type enzyme. Impaired catalysis of the Asp-170 variants is caused by slow flavin reduction. Furthermore, the mutant proteins have lost the capability of forming a stable complex between reduced enzyme and the p-quinone methide intermediate. The redox midpoint potentials in D170E (+6 mV) and D170S (-91 mV) are considerably decreased compared with wild type vanillyl-alcohol oxidase (+55 mV). This supports the idea that Asp-170 interacts with the protonated N5-atom of the reduced cofactor, thus increasing the FAD redox potential. Taken together, we conclude that Asp-170 is involved in the process of autocatalytic flavinylation and is crucial for efficient redox catalysis.
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Affiliation(s)
- R H van den Heuvel
- Department of Biomolecular Sciences, Laboratory of Biochemistry, Wageningen University, Dreijenlaan 3, 6703 HA Wageningen, The Netherlands
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29
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van Berkel WJ, van den Heuvel RH, Versluis C, Heck AJ. Detection of intact megaDalton protein assemblies of vanillyl-alcohol oxidase by mass spectrometry. Protein Sci 2000; 9:435-9. [PMID: 10752605 PMCID: PMC2144579 DOI: 10.1110/ps.9.3.435] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Well-resolved ion signals of intact large protein assemblies, with molecular masses extending above one million Dalton, have been detected and mass analyzed using electrospray ionization mass spectrometry, with an uncertainty in mass of <0.2%. The mass spectral data seem to reflect known solution-phase behavior of the studied protein assembly and have therefore been directly used to probe the protein assembly topology and stability as a function of ionic strength and pH.
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Affiliation(s)
- W J van Berkel
- Department of Biomolecular Sciences, Wageningen University, The Netherlands
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30
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Varela E, Böckle B, Romero A, Martínez AT, Martínez MJ. Biochemical characterization, cDNA cloning and protein crystallization of aryl-alcohol oxidase from Pleurotus pulmonarius. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1476:129-38. [PMID: 10606774 DOI: 10.1016/s0167-4838(99)00227-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Aryl-alcohol oxidase (AAO) involved in lignin degradation by Pleurotus pulmonarius has been purified and characterized. The enzyme was produced in glucose-peptone medium and isolated in a sole chromatographic step using Sephacryl S-200. The purified enzyme is an extracellular glycoprotein with 14% N-carbohydrate content and an estimated molecular mass of 70.5 kDa and pI of 3.95. The kinetic studies showed the highest enzyme affinity against p-anisyl alcohol, with constants similar to those of Pleurotus eryngii and Bjerkandera adusta AAO but different from the intracellular AAO described in Phanerochaete chrysosporium, which present the highest activity on m-anisyl alcohol. Simultaneously, the cDNA of P. pulmonarius AAO has been cloned and sequenced. The translation of this sequence consisted of 593 amino acids including a signal peptide of 27 amino acids. The comparison with other alcohol oxidases, 35% amino acid identity with glucose oxidase, showed highly conserved amino acid sequences in N-terminal and C-terminal regions, in spite of differences in substrate specificity. Crystallization of AAO, carried out for the first time using the P. pulmonarius enzyme, will permit to obtain a molecular model for this oxidase and establish some characteristic of its catalytic site and general structure.
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Affiliation(s)
- E Varela
- Centro de Investigaciones Biológicas, CSIC, Velázquez 144, E-28006, Madrid, Spain
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31
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Fraaije MW, van den Heuvel RH, van Berkel WJ, Mattevi A. Covalent flavinylation is essential for efficient redox catalysis in vanillyl-alcohol oxidase. J Biol Chem 1999; 274:35514-20. [PMID: 10585424 DOI: 10.1074/jbc.274.50.35514] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
By mutating the target residue of covalent flavinylation in vanillyl-alcohol oxidase, the functional role of the histidyl-FAD bond was studied. Three His(422) mutants (H422A, H422T, and H422C) were purified, which all contained tightly but noncovalently bound FAD. Steady state kinetics revealed that the mutants have retained enzyme activity, although the turnover rates have decreased by 1 order of magnitude. Stopped-flow analysis showed that the H422A mutant is still able to form a stable binary complex of reduced enzyme and a quinone methide product intermediate, a crucial step during vanillyl-alcohol oxidase-mediated catalysis. The only significant change in the catalytic cycle of the H422A mutant is a marked decrease in reduction rate. Redox potentials of both wild type and H422A vanillyl-alcohol oxidase have been determined. During reduction of H422A, a large portion of the neutral flavin semiquinone is observed. Using suitable reference dyes, the redox potentials for the two one-electron couples have been determined: -17 and -113 mV. Reduction of wild type enzyme did not result in any formation of flavin semiquinone and revealed a remarkably high redox potential of +55 mV. The marked decrease in redox potential caused by the missing covalent histidyl-FAD bond is reflected in the reduced rate of substrate-mediated flavin reduction limiting the turnover rate. Elucidation of the crystal structure of the H422A mutant established that deletion of the histidyl-FAD bond did not result in any significant structural changes. These results clearly indicate that covalent interaction of the isoalloxazine ring with the protein moiety can markedly increase the redox potential of the flavin cofactor, thereby facilitating redox catalysis. Thus, formation of a histidyl-FAD bond in specific flavoenzymes might have evolved as a way to contribute to the enhancement of their oxidative power.
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Affiliation(s)
- M W Fraaije
- Department of Genetics, University of Pavia, via Abbiategrasso 207, 27100 Pavia, Italy.
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Furukawa H, Wieser M, Morita H, Sugio T, Nagasawa T. Purification and characterization of vanillyl-alcohol oxidase from Byssochlamys fulva V107. J Biosci Bioeng 1999; 87:285-90. [PMID: 16232469 DOI: 10.1016/s1389-1723(99)80033-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/1998] [Accepted: 11/30/1998] [Indexed: 11/30/2022]
Abstract
Vanillyl-alcohol oxidase from Byssochlamys fulva V107 was purified to apparent homogeneity as shown by SDS-PAGE and gel-permeation HPLC. The enzyme is a homodimeric flavoenzyme consisting of two 58 kDa subunits. It catalyzes the dehydrogenation of different 4-hydroxybenzylic structures, including the conversion of 4-hydroxybenzyl alcohols such as vanillyl alcohol to the corresponding aldehydes, eugenol to coniferyl alcohol, and 4-alkylphenols to 1-(4-hydroxyphenyl)alcohols. The latter reaction was S-stereospecific and was used for the synthesis of S-1-(4-hydroxyphenyl)ethanol and -propanol with enantiomeric excesses of 81.9 and 86.0%, respectively. The catalytic and structural similarities to a Penicillium vanillyl-alcohol oxidase and Pseudomonas 4-alkylphenol methylhydroxylases are discussed.
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Affiliation(s)
- H Furukawa
- Department of Biological Function and Genetic Resources Science, Okayama University, Tsushima-Naka, Okayama 700-8530, Japan
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33
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van den Heuvel RH, Fraaije MW, Laane C, van Berkel WJ. Regio- and stereospecific conversion of 4-alkylphenols by the covalent flavoprotein vanillyl-alcohol oxidase. J Bacteriol 1998; 180:5646-51. [PMID: 9791114 PMCID: PMC107623 DOI: 10.1128/jb.180.21.5646-5651.1998] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The regio- and stereospecific conversion of prochiral 4-alkylphenols by the covalent flavoprotein vanillyl-alcohol oxidase was investigated. The enzyme was active, with 4-alkylphenols bearing aliphatic side chains of up to seven carbon atoms. Optimal catalytic efficiency occurred with 4-ethylphenol and 4-n-propylphenols. These short-chain 4-alkylphenols are stereoselectively hydroxylated to the corresponding (R)-1-(4'-hydroxyphenyl)alcohols (F. P. Drijfhout, M. W. Fraaije, H. Jongejan, W. J. H. van Berkel, and M. C. R. Franssen, Biotechnol. Bioeng. 59:171-177, 1998). (S)-1-(4'-Hydroxyphenyl)ethanol was found to be a far better substrate than (R)-1-(4'-hydroxyphenyl)ethanol, explaining why during the enzymatic conversion of 4-ethylphenol nearly no 4-hydroxyacetophenone is formed. Medium-chain 4-alkylphenols were exclusively converted by vanillyl-alcohol oxidase to the corresponding 1-(4'-hydroxyphenyl)alkenes. The relative cis-trans stereochemistry of these reactions was strongly dependent on the nature of the alkyl side chain. The enzymatic conversion of 4-sec-butylphenol resulted in two (4'-hydroxyphenyl)-sec-butene isomers with identical masses but different fragmentation patterns. We conclude that the water accessibility of the enzyme active site and the orientation of the hydrophobic alkyl side chain of the substrate are of major importance in determining the regiospecific and stereochemical outcome of vanillyl-alcohol oxidase-mediated conversions of 4-alkylphenols.
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Affiliation(s)
- R H van den Heuvel
- Laboratory of Biochemistry, Department of Biomolecular Sciences, Wageningen University Research Center, Wageningen, The Netherlands
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Fraaije MW, Van Berkel WJ, Benen JA, Visser J, Mattevi A. A novel oxidoreductase family sharing a conserved FAD-binding domain. Trends Biochem Sci 1998; 23:206-7. [PMID: 9644973 DOI: 10.1016/s0968-0004(98)01210-9] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- M W Fraaije
- Dept of Biomolecular Sciences, Wageningen Agricultural University, The Netherlands
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35
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Increasing the operational stability of flavoproteins by covalent cofactor binding. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0921-0423(98)80023-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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