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Kato H, Takahashi Y, Suzuki H, Ohashi K, Kawashima R, Nakamura K, Sakai K, Hori C, Takasuka TE, Kato M, Shimizu M. Identification and characterization of methoxy- and dimethoxyhydroquinone 1,2-dioxygenase from Phanerochaete chrysosporium. Appl Environ Microbiol 2024; 90:e0175323. [PMID: 38259078 PMCID: PMC10880611 DOI: 10.1128/aem.01753-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 12/15/2023] [Indexed: 01/24/2024] Open
Abstract
White-rot fungi, such as Phanerochaete chrysosporium, are the most efficient degraders of lignin, a major component of plant biomass. Enzymes produced by these fungi, such as lignin peroxidases and manganese peroxidases, break down lignin polymers into various aromatic compounds based on guaiacyl, syringyl, and hydroxyphenyl units. These intermediates are further degraded, and the aromatic ring is cleaved by 1,2,4-trihydroxybenzene dioxygenases. This study aimed to characterize homogentisate dioxygenase (HGD)-like proteins from P. chrysosporium that are strongly induced by the G-unit fragment of vanillin. We overexpressed two homologous recombinant HGDs, PcHGD1 and PcHGD2, in Escherichia coli. Both PcHGD1 and PcHGD2 catalyzed the ring cleavage in methoxyhydroquinone (MHQ) and dimethoxyhydroquinone (DMHQ). The two enzymes had the highest catalytic efficiency (kcat/Km) for MHQ, and therefore, we named PcHGD1 and PcHGD2 as MHQ dioxygenases 1 and 2 (PcMHQD1 and PcMHQD2), respectively, from P. chrysosporium. This is the first study to identify and characterize MHQ and DMHQ dioxygenase activities in members of the HGD superfamily. These findings highlight the unique and broad substrate spectra of PcHGDs, rendering them attractive candidates for biotechnological applications.IMPORTANCEThis study aimed to elucidate the properties of enzymes responsible for degrading lignin, a dominant natural polymer in terrestrial lignocellulosic biomass. We focused on two homogentisate dioxygenase (HGD) homologs from the white-rot fungus, P. chrysosporium, and investigated their roles in the degradation of lignin-derived aromatic compounds. In the P. chrysosporium genome database, PcMHQD1 and PcMHQD2 were annotated as HGDs that could cleave the aromatic rings of methoxyhydroquinone (MHQ) and dimethoxyhydroquinone (DMHQ) with a preference for MHQ. These findings suggest that MHQD1 and/or MHQD2 play important roles in the degradation of lignin-derived aromatic compounds by P. chrysosporium. The preference of PcMHQDs for MHQ and DMHQ not only highlights their potential for biotechnological applications but also underscores their critical role in understanding lignin degradation by a representative of white-rot fungus, P. chrysosporium.
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Affiliation(s)
- Hiroyuki Kato
- Faculty of Agriculture, Meijo University, Nagoya, Japan
| | | | | | - Keisuke Ohashi
- Faculty of Agriculture, Hokkaido University, Sapporo, Japan
| | | | - Koki Nakamura
- Faculty of Agriculture, Meijo University, Nagoya, Japan
| | - Kiyota Sakai
- Faculty of Agriculture, Meijo University, Nagoya, Japan
| | - Chiaki Hori
- Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Japan
| | | | - Masashi Kato
- Faculty of Agriculture, Meijo University, Nagoya, Japan
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Characterization of two 1,2,4-trihydroxybenzene 1,2-dioxygenases from Phanerochaete chrysosporium. Appl Microbiol Biotechnol 2022; 106:4499-4509. [PMID: 35687156 DOI: 10.1007/s00253-022-12007-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 05/21/2022] [Accepted: 05/27/2022] [Indexed: 11/02/2022]
Abstract
Lignin is the most abundant aromatic compound in nature, and it plays an important role in the carbon cycle. White-rot fungi are microbes that are capable of efficiently degrading lignin. Enzymes from these fungi possess exceptional oxidative potential and have gained increasing importance for improving bioprocesses, such as the degradation of organic pollutants. The aim of this study was to identify the enzymes involved in the ring cleavage of the lignin-derived aromatic 1,2,4-trihydroxybenzene (THB) in Phanerochaete chrysosporium, a lignin-degrading basidiomycete. Two intradiol dioxygenases (IDDs), PcIDD1 and PcIDD2, were identified and produced as recombinant proteins in Escherichia coli. In the presence of O2, PcIDD1 and PcIDD2 acted on eight and two THB derivatives, respectively, as substrates. PcIDD1 and PcIDD2 catalyze the ring cleavage of lignin-derived fragments, such as 6-methoxy-1,2,4-trihydroxybenzene (6-MeOTHB) and 3-methoxy-1,2-catechol. The current study also revealed that syringic acid (SA) was converted to 5-hydroxyvanillic acid, 2,6-dimethoxyhydroquinone, and 6-MeOTHB by fungal cells, suggesting that PcIDD1 and PcIDD2 may be involved in aromatic ring fission of 6-MeOTHB for SA degradation. This is the first study to show 6-MeOTHB dioxygenase activity of an IDD superfamily member. These findings highlight the unique and broad substrate spectra of PcIDDs, rendering it an attractive candidate for biotechnological application. KEY POINTS: • Novel intradiol dioxygenases (IDD) in lignin degradation were characterized. • PcIDDs acted on lignin-derived fragments and catechol derivatives. • Dioxygenase activity on 6-MeOTHB was identified in IDD superfamily enzymes.
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3
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Venkatesagowda B, Dekker RFH. Microbial demethylation of lignin: Evidence of enzymes participating in the removal of methyl/methoxyl groups. Enzyme Microb Technol 2021; 147:109780. [PMID: 33992403 DOI: 10.1016/j.enzmictec.2021.109780] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 02/27/2021] [Accepted: 03/11/2021] [Indexed: 11/30/2022]
Abstract
Lignin is an abundant natural plant aromatic biopolymer containing various functional groups that can be exploited for activating lignin for potential commercial applications. Applications are hindered due to the presence of a high content of methyl/methoxyl groups that affects reactiveness. Various chemical and enzymatic approaches have been investigated to increase the functionality in transforming lignin. Among these is demethylation/demethoxylation, which increases the potential numbers of vicinal hydroxyl groups for applications as phenol-formaldehyde resins. Although the chemical route to lignin demethylation is well-studied, the biological route is still poorly explored. Bacteria and fungi have the ability to demethylate lignin and lignin-related compounds. Considering that appropriate microorganisms possess the biochemical machinery to demethylate lignin by cleaving O-methyl groups liberating methanol, and modify lignin by increasing the vicinal diol content that allows lignin to substitute for phenol in organic polymer syntheses. Certain bacteria through the actions of specific O-demethylases can modify various lignin-related compounds generating vicinal diols and liberating methanol or formaldehyde as end-products. The enzymes include: cytochrome P450-aryl-O-demethylase, monooxygenase, veratrate 3-O-demethylase, DDVA O-demethylase (LigX; lignin-related biphenyl 5,5'-dehydrodivanillate (DDVA)), vanillate O-demethylase, syringate O-demethylase, and tetrahydrofolate-dependent-O-demethylase. Although, the fungal counterparts have not been investigated in depth as in bacteria, O-demethylases, nevertheless, have been reported in demethylating various lignin substrates providing evidence of a fungal enzyme system. Few fungi appear to have the ability to secrete O-demethylases. The fungi can mediate lignin demethylation enzymatically (laccase, lignin peroxidase, manganese peroxidase, O-demethylase), or non-enzymatically in brown-rot fungi through the Fenton reaction. This review discusses details on the aspects of microbial (bacterial and fungal) demethylation of lignins and lignin-model compounds and provides evidence of enzymes identified as specific O-demethylases involved in demethylation.
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Affiliation(s)
- Balaji Venkatesagowda
- Biorefining Research Institute, Lakehead University, Thunder Bay, Ontario, P7B 5E1, Canada.
| | - Robert F H Dekker
- Biorefining Research Institute, Lakehead University, Thunder Bay, Ontario, P7B 5E1, Canada; Universidade Tecnológica Federal do Paraná, Programa de Pós-Graduação em Engenharia Ambiental, Câmpus Londrina, CEP: 86036-370, Londrina, PR, Brazil.
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4
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Venkatesagowda B. Enzymatic demethylation of lignin for potential biobased polymer applications. FUNGAL BIOL REV 2019. [DOI: 10.1016/j.fbr.2019.06.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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5
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Loi M, Fanelli F, Zucca P, Liuzzi VC, Quintieri L, Cimmarusti MT, Monaci L, Haidukowski M, Logrieco AF, Sanjust E, Mulè G. Aflatoxin B₁ and M₁ Degradation by Lac2 from Pleurotus pulmonarius and Redox Mediators. Toxins (Basel) 2016; 8:toxins8090245. [PMID: 27563923 PMCID: PMC5037472 DOI: 10.3390/toxins8090245] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 08/03/2016] [Accepted: 08/15/2016] [Indexed: 02/07/2023] Open
Abstract
Laccases (LCs) are multicopper oxidases that find application as versatile biocatalysts for the green bioremediation of environmental pollutants and xenobiotics. In this study we elucidate the degrading activity of Lac2 pure enzyme form Pleurotus pulmonarius towards aflatoxin B1 (AFB1) and M1 (AFM1). LC enzyme was purified using three chromatographic steps and identified as Lac2 through zymogram and LC-MS/MS. The degradation assays were performed in vitro at 25 °C for 72 h in buffer solution. AFB1 degradation by Lac2 direct oxidation was 23%. Toxin degradation was also investigated in the presence of three redox mediators, (2,2′-azino-bis-[3-ethylbenzothiazoline-6-sulfonic acid]) (ABTS) and two naturally-occurring phenols, acetosyringone (AS) and syringaldehyde (SA). The direct effect of the enzyme and the mediated action of Lac2 with redox mediators univocally proved the correlation between Lac2 activity and aflatoxins degradation. The degradation of AFB1 was enhanced by the addition of all mediators at 10 mM, with AS being the most effective (90% of degradation). AFM1 was completely degraded by Lac2 with all mediators at 10 mM. The novelty of this study relies on the identification of a pure enzyme as capable of degrading AFB1 and, for the first time, AFM1, and on the evidence that the mechanism of an effective degradation occurs via the mediation of natural phenolic compounds. These results opened new perspective for Lac2 application in the food and feed supply chains as a biotransforming agent of AFB1 and AFM1.
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Affiliation(s)
- Martina Loi
- Institute of Sciences of Food Production, National Research Council of Italy (CNR), via Amendola 122/O, Bari 70126, Italy.
- Department of Economics, University of Foggia, via Napoli 25, Foggia 71122, Italy.
| | - Francesca Fanelli
- Institute of Sciences of Food Production, National Research Council of Italy (CNR), via Amendola 122/O, Bari 70126, Italy.
| | - Paolo Zucca
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Complesso Universitario, SP Monserrato-Sestu Km 0.700, Monserrato 09042, Italy.
| | - Vania C Liuzzi
- Institute of Sciences of Food Production, National Research Council of Italy (CNR), via Amendola 122/O, Bari 70126, Italy.
| | - Laura Quintieri
- Institute of Sciences of Food Production, National Research Council of Italy (CNR), via Amendola 122/O, Bari 70126, Italy.
| | - Maria T Cimmarusti
- Institute of Sciences of Food Production, National Research Council of Italy (CNR), via Amendola 122/O, Bari 70126, Italy.
- Department of Economics, University of Foggia, via Napoli 25, Foggia 71122, Italy.
| | - Linda Monaci
- Institute of Sciences of Food Production, National Research Council of Italy (CNR), via Amendola 122/O, Bari 70126, Italy.
| | - Miriam Haidukowski
- Institute of Sciences of Food Production, National Research Council of Italy (CNR), via Amendola 122/O, Bari 70126, Italy.
| | - Antonio F Logrieco
- Institute of Sciences of Food Production, National Research Council of Italy (CNR), via Amendola 122/O, Bari 70126, Italy.
| | - Enrico Sanjust
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Complesso Universitario, SP Monserrato-Sestu Km 0.700, Monserrato 09042, Italy.
| | - Giuseppina Mulè
- Institute of Sciences of Food Production, National Research Council of Italy (CNR), via Amendola 122/O, Bari 70126, Italy.
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Effects of Homologous Expression of 1,4-Benzoquinone Reductase and Homogentisate 1,2-Dioxygenase Genes on Wood Decay in Hyper-Lignin-Degrading Fungus Phanerochaete sordida YK-624. Curr Microbiol 2016; 73:512-8. [DOI: 10.1007/s00284-016-1089-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 06/21/2016] [Indexed: 10/21/2022]
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7
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Zucca P, Cocco G, Sollai F, Sanjust E. Fungal laccases as tools for biodegradation of industrial dyes. ACTA ACUST UNITED AC 2016. [DOI: 10.1515/boca-2015-0007] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractLaccases are blue copper oxidases, found in some plants and secreted by a wide range of ligninolytic fungi. These enzymes are well known for their ability in oxidizing several organic compounds, mainly phenolics and aromatic amines, at the expenses of molecular oxygen. Therefore, they could find application in the field of enzymatic bioremediation of many industrial wastewaters, and in particular to bleach and/or detoxify dye-containing effluents. Not all industrial dyes behave as laccase substrates, but this limitation is often overcome by the judicious use of redox mediators. These could substantially widen the application range of laccases as bioremediation tools. The present study encompasses the main properties of the most used industrial dyes as related to their chemical classification, fungal laccases and their molecular and catalytic features, the use of redox mediators, limitations and perspectives of the use of fungal laccases for industrial dye bleaching.
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8
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9
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Sietmann R, Uebe R, Böer E, Bode R, Kunze G, Schauer F. Novel metabolic routes during the oxidation of hydroxylated aromatic acids by the yeast Arxula adeninivorans. J Appl Microbiol 2009; 108:789-799. [PMID: 19702859 DOI: 10.1111/j.1365-2672.2009.04474.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM To complete our study on tannin degradation via gallic acid by the biotechnologically interesting yeast Arxula adeninivorans as well as to characterize new degradation pathways of hydroxylated aromatic acids. METHODS AND RESULTS With glucose-grown cells of A. adeninivorans, transformation experiments with hydroxylated derivatives of benzoic acid were carried out. The 12 metabolites were analysed and identified by high performance liquid chromatography and GC/MS. The yeast is able to transform the derivatives by oxidative and nonoxidative decarboxylation as well as by methoxylation. The products of nonoxidative decarboxylation of protocatechuate and gallic acid are substrates for further ring fission. CONCLUSION Whereas other organisms use only one route of transformation, A. adeninivorans is able to carry out three different pathways (oxidative, nonoxidative decarboxylation and methoxylation) on one hydroxylated aromatic acid. The determination of the KM-values for protocatechuate and gallic acid in crude extracts of cells of A. adeninivorans cultivated with protocatechuate and gallic acid, respectively, suggests that the decarboxylation of protocatechuate and gallic acid may be catalysed by the same enzyme. SIGNIFICANCE AND IMPACT OF THE STUDY This transformation pathway of protocatechuate and gallic acid via nonoxidative decarboxylation up to ring fission is novel and has not been described so far. This is also the first report of nonoxidative decarboxylation of gallic acid by a eukaryotic micro-organism.
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Affiliation(s)
- R Sietmann
- Institute of Microbiology, Ernst-Moritz-Arndt-University of Greifswald, Greifswald, Germany
| | - R Uebe
- Institute of Microbiology, Ernst-Moritz-Arndt-University of Greifswald, Greifswald, Germany
| | - E Böer
- Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - R Bode
- Institute of Microbiology, Ernst-Moritz-Arndt-University of Greifswald, Greifswald, Germany
| | - G Kunze
- Leibniz Institute of Plant Genetics and Crop Plant Research, Gatersleben, Germany
| | - F Schauer
- Institute of Microbiology, Ernst-Moritz-Arndt-University of Greifswald, Greifswald, Germany
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10
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11
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Niemenmaa O, Uusi-Rauva A, Hatakka A. Wood stimulates the demethoxylation of [O14CH3]-labeled lignin model compounds by the white-rot fungi Phanerochaete chrysosporium and Phlebia radiata. Arch Microbiol 2006; 185:307-15. [PMID: 16502311 DOI: 10.1007/s00203-006-0097-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2003] [Revised: 02/01/2006] [Accepted: 02/07/2006] [Indexed: 10/25/2022]
Abstract
Mineralization of polymeric wood lignin and its substructures is a result of complex reactions involving oxidizing and reducing enzymes and radicals. The degradation of methoxyl groups is an essential part of this process. The presence of wood greatly stimulates the demethoxylation of a non-phenolic lignin model compound (a [O(14)CH(3)]-labeled beta-O-4 dimer) by the lignin-degrading white-rot fungi Phlebia radiata and Phanerochaete chrysosporium. When grown on wood, both fungi produced up to 47 and 40% (14)CO(2) of the applied (14)C activity, respectively, under air and oxygen in 8 weeks. Without wood, the demethoxylation of the dimer by both fungi was lower, varying between 0.5 and 35%. Addition of nutrient nitrogen together with glucose decreased demethoxylation when the fungi were grown on spruce wood under air. Because the evolution of (14)CO(2) in the absence of wood was poor, the fungi may have preferably used wood as a carbon and nitrogen source. The amount of fungal mycelium, as determined by the ergosterol assay, did not show connection to demethoxylation. P. radiata also showed a high demethoxylation of [O(14)CH(3)]-labeled vanillic acid in the presence of birch wood. The degradation of lignin and lignin-related substances should be studied in the presence of wood, the natural substrate for white-rot fungi.
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Affiliation(s)
- Outi Niemenmaa
- Department of Applied Chemistry and Microbiology, University of Helsinki, Viikki Biocenter, Viikinkaari 9, P.O. Box 56, 00014, Helsinki, Finland
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12
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13
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Guillén F, Martínez MJ, Muñoz C, Martínez AT. Quinone redox cycling in the ligninolytic fungus Pleurotus eryngii leading to extracellular production of superoxide anion radical. Arch Biochem Biophys 1997; 339:190-9. [PMID: 9056249 DOI: 10.1006/abbi.1996.9834] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Quinone redox cycling is generally known as an intracellular process that implies the reduction of quinones (Q) into semiquinones (Q-.) or hydroquinones (QH2), which autoxidize reducing oxygen to superoxide anion radical (O-.2). We demonstrate here for the first time the existence of quinone redox cycling in a ligninolytic fungus, Pleurotus eryngii, showing two particularities: extracellular production of O-.2 and involvement of ligninolytic enzymes. Experiments were performed with P. eryngii cultures, showing laccase activity, and four quinones: 1,4-benzoquinone (BQ), 2-methyl-1,4-benzoquinone (MeBQ), 2,3,5,6-tetramethyl-1,4-benzoquinone (duroquinone, DQ), and 2-methyl-1,4-naphthoquinone (menadione, MD). The overall process consisted of cell-bound divalent reduction of quinones, followed by extracellular laccase-mediated oxidation of hydroquinones into semiquinones, which autoxidized to a certain extent producing O-.2 (at the pH values of natural degradation of lignin, some autoxidation of hydroquinones was observed only with DQH2 and MDH2). The existence of a redox cyclic system involving quinones was evidenced by determining the chemical state of quinones along incubation under several conditions (either different O2 concentrations and pH values or laccase amounts). Thus, QH2/Q ratios at system equilibrium decreased as either pH values and oxygen concentration (allowing hydroquinones autoxidation) or the amount of laccase increased. Once the cyclic nature of the system was demonstrated, special attention was paid to the production of O-.2 during hydroquinone oxidation. Except in the case of BQH2, production of O-.2 was found in samples containing hydroquinones and laccase. By the use of agents promoting the autoxidation of semiquinones (superoxide dismutase and Mn2+), production of O-.2 during oxidation of BQH2 could finally be demonstrated.
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Affiliation(s)
- F Guillén
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Velázquez, Madrid, Spain
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Abstract
Evidence in support of an essential role for H
2
O
2
in lignin degradation by the white-rot fungus
Phanerochaete chrysosporium
has been presented by several laboratories. H
2
O
2
is formed simultaneously with the ligninolytic system, and when it is degraded by catalase the lignin-degrading capacity is also reduced. We have now identified, purified and characterized a sugar-oxidizing enzyme that produces H
2
O
2
during glucose starvation in
P. chrysosporium
. The enzyme oxidizes glucose at the 2-carbon position to yield glucosone, but 5-n-gluconolactone and xylose are also oxidized at significant rates. Another H
2
O
2
-producing enzyme in
P.chrysosporium
, methanol oxidase, has also been identified, purified and characterized in this laboratory. Methanol is formed from the methoxyl groups in lignin. Hydrogen peroxide, necessary for further degradation of lignin, is formed by enzyme-catalysed oxidation of the lignin-derived methanol. Induction and repression of the H
2
O
2
-producing enzymes is discussed, as well as ways for the fungus to control the glucose level in its environment.
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Rieble S, Joshi DK, Gold MH. Purification and characterization of a 1,2,4-trihydroxybenzene 1,2-dioxygenase from the basidiomycete Phanerochaete chrysosporium. J Bacteriol 1994; 176:4838-44. [PMID: 8050996 PMCID: PMC196317 DOI: 10.1128/jb.176.16.4838-4844.1994] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
1,2,4-Trihydroxybenzene (THB) is an intermediate in the Phanerochaete chrysosporium degradation of vanillate and aromatic pollutants. A P. chrysosporium intracellular enzyme able to oxidatively cleave the aromatic ring of THB was purified by ammonium sulfate precipitation, hydrophobic and ion-exchange chromatographies, and native gel electrophoresis. The native protein has a molecular mass of 90 kDa and a subunit mass of 45 kDa. The enzyme catalyzes an intradiol cleavage of the substrate aromatic ring to produce maleylacetate. 18O2 incorporation studies demonstrate that molecular oxygen is a cosubstrate in the reaction. The enzyme exhibits high substrate specificity for THB; however, catechol cleavage occurs at approximately 20% of the optimal rate. THB dioxygenase catalyzes a key step in the degradation pathway of vanillate, an intermediate in lignin degradation. Maleylacetate, the product of THB cleavage, is reduced to beta-ketoadipate by an NADPH-requiring enzyme present in partially purified extracts.
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Affiliation(s)
- S Rieble
- Department of Chemistry, Biochemistry and Molecular Biology, Oregon Graduate Institute of Science and Technology, Portland 97291-1000
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Malarczyk E, Rogalski J, Leonowicz A. Transformation of ferulic acid by soil bacteriaNocardia provides various valuable phenolic compounds. ACTA ACUST UNITED AC 1994. [DOI: 10.1002/abio.370140304] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Rajarathnam S, Shashireka MN, Bano Z. Biopotentialities of the basidiomacromycetes. ADVANCES IN APPLIED MICROBIOLOGY 1992; 37:233-361. [PMID: 1642158 DOI: 10.1016/s0065-2164(08)70256-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- S Rajarathnam
- Central Food Technological Research Institute, Mysore, India
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Lundell T, Leonowicz A, Rogalski J, Hatakka A. Formation and Action of Lignin-Modifying Enzymes in Cultures of
Phlebia radiata
Supplemented with Veratric Acid. Appl Environ Microbiol 1990; 56:2623-9. [PMID: 16348272 PMCID: PMC184811 DOI: 10.1128/aem.56.9.2623-2629.1990] [Citation(s) in RCA: 63] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transformation of veratric (3,4-dimethoxybenzoic) acid by the white rot fungus
Phlebia radiata
was studied to elucidate the role of ligninolytic, reductive, and demeth(ox)ylating enzymes. Under both air and a 100% O
2
atmosphere, with nitrogen limitation and glucose as a carbon source, reducing activity resulted in the accumulation of veratryl alcohol in the medium. When the fungus was cultivated under air, veratric acid caused a rapid increase in laccase (benzenediol:oxygen oxidoreductase; EC 1.10.3.2) production, which indicated that veratric acid was first demethylated, thus providing phenolic compounds for laccase. After a rapid decline in laccase activity, elevated lignin peroxidase (ligninase) activity and manganese-dependent peroxidase production were detected simultaneously with extracellular release of methanol. This indicated apparent demethoxylation. When the fungus was cultivated under a continuous 100% O
2
flow and in the presence of veratric acid, laccase production was markedly repressed, whereas production of lignin peroxidase and degradation of veratryl compounds were clearly enhanced. In all cultures, the increases in lignin peroxidase titers were directly related to veratryl alcohol accumulation. Evolution of
14
CO
2
from 3-O
14
CH
3
-and 4-O
14
CH
3
-labeled veratric acids showed that the position of the methoxyl substituent in the aromatic ring only slightly affected demeth(ox)ylation activity. In both cases, more than 60% of the total
14
C was converted to
14
CO
2
under air in 4 weeks, and oxygen flux increased the degradation rate of the
14
C-labeled veratric acids just as it did with unlabeled cultures.
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Affiliation(s)
- T Lundell
- Department of Microbiology, University of Helsinki, SF-00710 Helsinki, Finland, and Department of Biochemistry, University of Maria Curie-Sklodowska, PL-20-031 Lublin, Poland
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Redox reactions in lignin degradation: interactions between laccase, different peroxidases and cellobiose: quinone oxidoreductase. J Biotechnol 1990. [DOI: 10.1016/0168-1656(90)90104-j] [Citation(s) in RCA: 66] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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21
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Rahouti M, Seigle-Murandi F, Steiman R, Eriksson KE. Metabolism of Ferulic Acid by
Paecilomyces variotii
and
Pestalotia palmarum. Appl Environ Microbiol 1989; 55:2391-8. [PMID: 16348018 PMCID: PMC203086 DOI: 10.1128/aem.55.9.2391-2398.1989] [Citation(s) in RCA: 89] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Ferulic acid metabolism was studied in cultures of two micromycetes producing different amounts of phenol oxidases. In cultures of the low phenol oxidase producer
Paecilomyces variotii
, ferulic acid was decarboxylated to 4-vinylguaiacol, which was converted to vanillin and then either oxidized to vanillic acid or reduced to vanillyl alcohol. Vanillic acid underwent simultaneously an oxidative decarboxylation to methoxyhydroquinone and a nonoxidative decarboxylation to guaiacol. Methoxyhydroquinone and guaiacol were demethylated to yield hydroxyquinol and catechol, respectively. Catechol was hydroxylated to pyrogallol. Degradation of ferulic acid by
Paecilomyces variotii
proceeded mainly via methoxyhydroquinone. The high phenol oxidase producer
Pestalotia palmarum
catabolized ferulic acid via 4-vinylguaiacol, vanillin, vanillyl alcohol, vanillic acid, and methoxyhydroquinone. However, the main reactions observed with this fungus involved polymerization reactions.
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Affiliation(s)
- M Rahouti
- Laboratoire de Botanique, Cryptogamie, Biologie Cellulaire et Génétique, 38243 Meylan, France, and Department of Biochemistry, The University of Georgia, Athens, Georgia 30602
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22
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Rajarathnam S, Bano Z. Pleurotus mushrooms. Part III. Biotransformations of natural lignocellulosic wastes: commercial applications and implications. Crit Rev Food Sci Nutr 1989; 28:31-113. [PMID: 2647418 DOI: 10.1080/10408398909527491] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Species of Pleurotus are endowed with the capacity to degrade unfermented natural lignino-cellulosic wastes. From the time the substrate is spawned until the end of cropping, there occurs a spectrum of qualitative and quantitative changes in the various substrate constituents, viz., cellulose, hemicellulose, lignin, sugars, amino acids, phenols, ash, nitrogen, etc. In general, cellulose, hemicellulose, and lignin are degraded, solubility of the substrate is increased, phenolic content is decreased, sugar and amino acid contents are increased, as is the ash content due to a constant utilization of the organic matter. The ability of Pleurotus to effect these degradative changes is discussed under both sterile (monoculture) and nonsterile culturing conditions. The enzymatic aspects affecting these various chemical changes in the lignino-cellulosic substrates are brought out. The various commercial applications and implications of the spent substrate, such as use as an upgraded form of ruminant feed, production of biogas, manufacture of paper/cardboard, recycling into Agaricus compost, garden fertilizer, production of single cell proteins, etc., are critically evaluated.
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Affiliation(s)
- S Rajarathnam
- Discipline of Fruits, Vegetables, and Plantation Crops, Central Food Technological Research Institute, Mysore, India
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23
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Rajarathnam S, Bano Z. Pleurotus mushrooms. Part IB. Pathology, in vitro and in vivo growth requirements, and world status. Crit Rev Food Sci Nutr 1988; 26:243-311. [PMID: 3280248 DOI: 10.1080/10408398809527469] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Part IB of this review discusses growth abnormalities and diseases of the fruit bodies, as well as containments in the substrates that affect the quality and yield of the fruit bodies. The means and methods to overcome these problems during culturing of Pleurotus on commercial scales are described. In vitro growth requirements and prospects of producing mycelium on organic wastes in liquid culture are discussed. The effects of changes in the nutrients of growth substrate on the yield and quality of fruit bodies in vivo are brought out. Status of culturing Pleurotus in different parts of the world is evaluated. Finally, a critical consideration of the scope and problems of Pleurotus cultivation technology is given.
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Affiliation(s)
- S Rajarathnam
- Fruit and Vegetable Technology Discipline, Central Food Technological Research Institute, Mysore, India
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24
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Frazer AC, Bossert I, Young LY. Enzymatic Aryl-O-Methyl-
14
C Labeling of Model Lignin Monomers. Appl Environ Microbiol 1986; 51:80-3. [PMID: 16346977 PMCID: PMC238818 DOI: 10.1128/aem.51.1.80-83.1986] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Aryl-
O
-methyl ethers are abundant in aerobic and anaerobic environments. In particular, lignin is composed of units of this type. Lignin monomers specifically radiolabeled in methoxy, side chain, and ring carbons have been synthesized by chemical procedures and are important in studies of lignin synthesis and degradation, humus formation, and microbial O-demethylation. In this paper attention is drawn to an enzymatic procedure for preparing O-methyl-
14
C-labeled aromatic lignin monomers which has not previously been exploited in microbial ecology and physiology studies and which has several advantages compared with chemical synthesis procedures.
O
-[
methyl
-
14
C]vanillic and
O
-[
methyl
-
14
C]ferulic acids were prepared with
S
-[
methyl
-
14
C]adenosyl-
l
-methionine as the methyl donor, using commercially obtained porcine liver catechol-
O
-methyltransferase (EC 2.1.1.6). The specific activity of the methylated products was the same as that of the methyl donor, a maximum of about 58 μCi/μmol, and the yields were 42% (vanillate) and 35% (ferulate). Thus lignin monomers are readily prepared as O-methylated products of the catechol-
O
-methyltransferase reaction and, with this enzyme method of preparation, would be more widely available than labeled compounds which require chemical synthesis.
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Affiliation(s)
- A C Frazer
- Department of Microbiology, and Department of Environmental Medicine, New York University Medical Center, New York, New York 10016
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25
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Degradation of veratric acid and other lignin-related aromatic compounds by the white-rot fungus Pycnoporus cinnabarinus. Arch Microbiol 1985. [DOI: 10.1007/bf00446734] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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26
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27
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28
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Ander P, Eriksson KE, Yu HS. Physiological requirements for degradation of lignin and lignin-related substances by Sporotrichum pulverulentum. ACTA ACUST UNITED AC 1983. [DOI: 10.1007/bf00504748] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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29
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Eriksson KE, Johnsrud SC, Vallander L. Degradation of lignin and lignin model compounds by various mutants of the white-rot fungus Sporotrichum pulverulentum. Arch Microbiol 1983. [DOI: 10.1007/bf00414473] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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