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Brescia FF, Korf L, Essen LO, Zorn H, Ruehl M. A Novel O- and S-Methyltransferase from Pleurotus sapidus Is Involved in Flavor Formation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:6471-6480. [PMID: 38462720 DOI: 10.1021/acs.jafc.3c08849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Increasing consumer aversion to non-natural flavoring substances is prompting a heightened interest in enzymatic processes for flavor production. This includes methylation reactions, which are often performed by using hazardous chemicals. By correlation of aroma profile data and transcriptomic analysis, a novel O-methyltransferase (OMT) catalyzing a respective reaction within the formation of p-anisaldehyde was identified in the mushroom Pleurotus sapidus. Heterologous expression in E. coli followed by purification allowed for further characterization of the enzyme. Besides p-hydroxybenzaldehyde, the proposed precursor of p-anisaldehyde, the enzyme catalyzed the methylation of further hydroxylated aromatic compounds at the meta- and para-position. The Km values determined for p-hydroxybenzaldehyde and S-adenosyl-l-methionine were 80 and 107 μM, respectively. Surprisingly, the studied enzyme enabled the transmethylation of thiol-nucleophiles, as indicated by the formation of 2-methyl-3-(methylthio)furan from 2-methyl-3-furanthiol. Moreover, the enzyme was crystallized at a resolution of 2.0 Å, representing the first published crystal structure of a basidiomycetous OMT.
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Affiliation(s)
- Fabio Francesco Brescia
- Institute of Food Chemistry and Food Biotechnology, Justus Liebig University Giessen, Heinrich-Buff-Ring 17, Giessen 35392, Germany
| | - Lukas Korf
- Institute of Biochemistry, Philips University Marburg, Hans-Meerwein-Str. 4, Marburg 35032, Germany
| | - Lars-Oliver Essen
- Institute of Biochemistry, Philips University Marburg, Hans-Meerwein-Str. 4, Marburg 35032, Germany
| | - Holger Zorn
- Institute of Food Chemistry and Food Biotechnology, Justus Liebig University Giessen, Heinrich-Buff-Ring 17, Giessen 35392, Germany
- Fraunhofer Institute for Molecular Biology and Applied Ecology, Ohlebergsweg 12, Giessen 35392, Germany
| | - Martin Ruehl
- Institute of Food Chemistry and Food Biotechnology, Justus Liebig University Giessen, Heinrich-Buff-Ring 17, Giessen 35392, Germany
- Fraunhofer Institute for Molecular Biology and Applied Ecology, Ohlebergsweg 12, Giessen 35392, Germany
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Liu J, Ye L, Jing C. Active microbial arsenic methylation in saline-alkaline paddy soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 865:161077. [PMID: 36572312 DOI: 10.1016/j.scitotenv.2022.161077] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 12/16/2022] [Accepted: 12/16/2022] [Indexed: 06/17/2023]
Abstract
Seawater rice has been cultivated to ensure food security. The salt-tolerant rice strains are resistant to saline and alkali but may be vulnerable to elevated arsenic (As) near coastal regions. Herein, the saline-alkaline paddy soil was incubated with natural irrigation river for three months to explore the mobility and transformation of As. The incubation results showed that 65 ± 1.2 % solid-bound As(V) was reduced to As(III) within two weeks with the release of As(III) to porewater. The dissolved As(III) was methylated after two weeks, resulting in dimethyl arsenate (DMA) as the dominant As species (87 %-100 %). The elevated As methylation was attributed to the most abundant arsenite methyltransferase gene (arsM) (4.1-10.4 × 107/g dry soil), over three orders of magnitude higher than As redox-related genes. The analysis of arsM operational taxonomic units (OTUs) suggested the highest sequence similarity to Proteobacteria (25.7-39.5 %), Actinobacteria (24.9-30.5 %), Gemmatimonadetes (7.5-11.9 %), Basidiomycota (5.1-12.5 %), and Chloroflexi (4.1-8.7 %). Specifically, Chloroflexi and Actinobacteria are salt-tolerant bacteria, probably responsible for As methylation. The As in grain was within a safe regulatory level, and the dominance of methylated As in porewater did not enhance its accumulation in rice grains.
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Affiliation(s)
- Jing Liu
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Li Ye
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China
| | - Chuanyong Jing
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao 266237, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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Zhang C, Sultan SA, T R, Chen X. Biotechnological applications of S-adenosyl-methionine-dependent methyltransferases for natural products biosynthesis and diversification. BIORESOUR BIOPROCESS 2021; 8:72. [PMID: 38650197 PMCID: PMC10992897 DOI: 10.1186/s40643-021-00425-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/31/2021] [Indexed: 12/28/2022] Open
Abstract
In the biosynthesis of natural products, methylation is a common and essential transformation to alter molecules' bioavailability and bioactivity. The main methylation reaction is performed by S-adenosylmethionine (SAM)-dependent methyltransferases (MTs). With advancements in genomic and chemical profiling technologies, novel MTs have been discovered to accept complex substrates and synthesize industrially valuable natural products. However, to achieve a high yield of small molecules in microbial hosts, many methyltransferase activities have been reported to be insufficient. Moreover, inadequate co-factor supplies and feedback inhibition of the by-product, S-adenosylhomocysteine (SAH), further limit MTs' activities. Here, we review recent advances in SAM-dependent MTs to produce and diversify natural products. First, we surveyed recently identified novel methyltransferases in natural product biosynthesis. Second, we summarized enzyme engineering strategies to improve methyltransferase activity, with a particular focus on high-throughput assay design and application. Finally, we reviewed innovations in co-factor regeneration and diversification, both in vitro and in vivo. Noteworthily, many MTs are able to accept multiple structurally similar substrates. Such promiscuous methyltransferases are versatile and can be tailored to design de novo pathways to produce molecules whose biosynthetic pathway is unknown or non-existent in nature, thus broadening the scope of biosynthesized functional molecules.
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Affiliation(s)
- Congqiang Zhang
- Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology and Research (A*STAR), 61 Biopolis Drive, Singapore, 138673, Singapore
| | - Stella Amelia Sultan
- Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology and Research (A*STAR), 61 Biopolis Drive, Singapore, 138673, Singapore
| | - Rehka T
- Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology and Research (A*STAR), 61 Biopolis Drive, Singapore, 138673, Singapore
| | - Xixian Chen
- Singapore Institute of Food and Biotechnology Innovation (SIFBI), Agency for Science, Technology and Research (A*STAR), 61 Biopolis Drive, Singapore, 138673, Singapore.
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Wickramasinghe PCK, Munafo JP. Biosynthesis of Benzylic Derivatives in the Fermentation Broth of the Edible Mushroom, Ischnoderma resinosum. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:2485-2492. [PMID: 32049524 DOI: 10.1021/acs.jafc.9b07218] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Employing isotope incubation studies, the biosynthetic pathway leading to a series of benzylic derivatives was elucidated in the fermentation broth of the edible mushroom Ischnoderma resinosum (P. Karst). Twenty-six hydroxy- and methoxy- benzylic derivatives were screened by gas chromatography-mass spectrometry (GC-MS) of which 13 were detected in the culture media. Results from the isotope incubation studies showed the transformation of both benzyl alcohol and benzoic acid into benzaldehyde. Benzaldehyde was then converted into 4-methoxybenzaldehyde via hydroxylation and subsequent methylation of the 4-C position. The resulting 4-methoxybenzaldehyde was then hydroxylated in the 3-C position followed by methylation into 3,4-dimethoxybenzaldehyde. Based on these findings, a novel metabolic scheme for the biosynthesis of benzylic derivatives in I. resinosum was proposed. The knowledge of the biosynthetic pathway was utilized to produce 4-hydroxy-3-methoxybenzaldehyde (vanillin) from 4-hydroxy-3-methoxybenzoic acid (vanillic acid). This is the first report to elucidate the biosynthetic pathway of benzyl derivatives and production of vanillin from I. resinosum.
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Affiliation(s)
- Purni C K Wickramasinghe
- Department of Food Science , The University of Tennessee , Knoxville , Tennessee 37996 , United States
| | - John P Munafo
- Department of Food Science , The University of Tennessee , Knoxville , Tennessee 37996 , United States
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Mäkelä MR, Hildén K, Kowalczyk JE, Hatakka A. Progress and Research Needs of Plant Biomass Degradation by Basidiomycete Fungi. GRAND CHALLENGES IN FUNGAL BIOTECHNOLOGY 2020. [DOI: 10.1007/978-3-030-29541-7_15] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Kovalchuk A, Zeng Z, Ghimire RP, Kivimäenpää M, Raffaello T, Liu M, Mukrimin M, Kasanen R, Sun H, Julkunen-Tiitto R, Holopainen JK, Asiegbu FO. Dual RNA-seq analysis provides new insights into interactions between Norway spruce and necrotrophic pathogen Heterobasidion annosum s.l. BMC PLANT BIOLOGY 2019; 19:2. [PMID: 30606115 PMCID: PMC6318961 DOI: 10.1186/s12870-018-1602-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 12/12/2018] [Indexed: 05/10/2023]
Abstract
BACKGROUND Root and butt rot of conifer trees caused by fungi belonging to the Heterobasidion annosum species complex is one of the most economically important fungal diseases in commercial conifer plantations throughout the Northern hemisphere. We investigated the interactions between Heterobasidion fungi and their host by conducting dual RNA-seq and chemical analysis on Norway spruce trees naturally infected by Heterobasidion spp. We analyzed host and pathogen transcriptome and phenolic and terpenoid contents of the spruce trees. RESULTS Presented results emphasize the role of the phenylpropanoid and flavonoid pathways in the chemical defense of Norway spruce trees. Accumulation of lignans was observed in trees displaying symptoms of wood decay. A number of candidate genes with a predicted role in the higher level regulation of spruce defense responses were identified. Our data indicate a possible role of abscisic acid (ABA) signaling in the spruce defense against Heterobasidion infection. Fungal transcripts corresponding to genes encoding carbohydrate- and lignin-degrading enzymes, secondary metabolism genes and effector-like genes were expressed during the host colonization. CONCLUSIONS Our results provide additional insight into defense strategies employed by Norway spruce trees against Heterobasidion infection. The potential applications of the identified candidate genes as markers for higher resistance against root and butt rot deserve further evaluation.
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Affiliation(s)
- Andriy Kovalchuk
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, P.O. Box 27, FIN-00014 Helsinki, Finland
| | - Zhen Zeng
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, P.O. Box 27, FIN-00014 Helsinki, Finland
| | - Rajendra P. Ghimire
- Department of Environmental and Biological Sciences, Kuopio Campus, University of Eastern Finland (UEF), P.O. Box 1627, FIN-70211 Kuopio, Finland
| | - Minna Kivimäenpää
- Department of Environmental and Biological Sciences, Kuopio Campus, University of Eastern Finland (UEF), P.O. Box 1627, FIN-70211 Kuopio, Finland
| | - Tommaso Raffaello
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, P.O. Box 27, FIN-00014 Helsinki, Finland
| | - Mengxia Liu
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, P.O. Box 27, FIN-00014 Helsinki, Finland
| | - Mukrimin Mukrimin
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, P.O. Box 27, FIN-00014 Helsinki, Finland
- Department of Forestry, Universitas Hasanuddin, Jln. Perintis Kemerdekaan Km. 10, Makassar, 90245 Indonesia
| | - Risto Kasanen
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, P.O. Box 27, FIN-00014 Helsinki, Finland
| | - Hui Sun
- Collaborative Innovation Center of Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China
| | - Riitta Julkunen-Tiitto
- Department of Environmental and Biological Sciences, Joensuu Campus, University of Eastern Finland (UEF), P.O. Box 111, FIN-80101 Joensuu, Finland
| | - Jarmo K. Holopainen
- Department of Environmental and Biological Sciences, Kuopio Campus, University of Eastern Finland (UEF), P.O. Box 1627, FIN-70211 Kuopio, Finland
| | - Fred O. Asiegbu
- Department of Forest Sciences, Faculty of Agriculture and Forestry, University of Helsinki, P.O. Box 27, FIN-00014 Helsinki, Finland
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Pan L, Sun J, Le XC, Zhu L. Effect of copper on the translocation and transformation of polychlorinated biphenyls in rice. CHEMOSPHERE 2018; 193:514-520. [PMID: 29169126 DOI: 10.1016/j.chemosphere.2017.11.054] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Revised: 11/09/2017] [Accepted: 11/12/2017] [Indexed: 06/07/2023]
Abstract
Contamination of organic pollutants in the environment is usually accompanied by heavy metals. However, a little information on the influences of heavy metals on the uptake, translocation and transformation of organic pollutants in plants is available. In this study, ten-day hydroponic exposure was conducted to explore the influence of copper (Cu) on the bioaccumulation and biotransformation of polychlorinated biphenyls (PCBs) in intact young rice (Oryza sativa L.). Low dose of Cu (≤100 μmol/L) increased the accumulation of CB-61 in rice plants, while excess concentrations of Cu (>100 μmol/L) inhibited uptake and translocation of CB-61. Effect of Cu on the uptake of CB-61 was attributed to the Cu-triggered damage to the roots of rice plants. The presence of a moderate dose of Cu (50 μmol/L) enhanced the formation of hydroxylated polychlorinated biphenyls (OH-PCBs) and methoxylated polychlorinated biphenyls (MeO-PCBs), whereas excess concentrations of Cu (250 μmol/L) inhibited the metabolism of CB-61. The effect of Cu on the interconversion between 4'-OH-CB-61 and 4'-MeO-CB-61 was also concentration dependent: the biotransformation was promoted by a moderate concentration of Cu but inhibited by excess concentrations of Cu. The activities of Cytochrome P450 (CYP450) and S-adenosyl-l-methionine (SAM)-dependent methyltransferase in the roots of rice plants exposed to Cu and CB-61 or its derivatives were consistent with the pattern and trend of the metabolites observed in rice roots. These results could provide valuable insights into the interactions and combined effects of PCBs and heavy metals in plants.
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Affiliation(s)
- Lili Pan
- Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang, 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang, 310058, China
| | - Jianteng Sun
- Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang, 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang, 310058, China
| | - X Chris Le
- Department of Chemistry and Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, T6G 2G3, Canada
| | - Lizhong Zhu
- Department of Environmental Science, Zhejiang University, Hangzhou, Zhejiang, 310058, China; Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control, Hangzhou, Zhejiang, 310058, China.
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Bhatter P, Raman K, Janakiraman V. Elucidating the biosynthetic pathways of volatile organic compounds in Mycobacterium tuberculosis through a computational approach. MOLECULAR BIOSYSTEMS 2017; 13:750-755. [DOI: 10.1039/c6mb00796a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A first report on the biosynthetic origin ofMycobacterium tuberculosisspecific small volatile molecules.
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Affiliation(s)
- Purva Bhatter
- Department of Biotechnology
- Bhupat and Jyoti Mehta School of Biosciences
- Indian Institute of Technology Madras
- Chennai – 600 036
- India
| | - Karthik Raman
- Department of Biotechnology
- Bhupat and Jyoti Mehta School of Biosciences
- Indian Institute of Technology Madras
- Chennai – 600 036
- India
| | - Vani Janakiraman
- Department of Biotechnology
- Bhupat and Jyoti Mehta School of Biosciences
- Indian Institute of Technology Madras
- Chennai – 600 036
- India
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9
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Discovery and characterization of new O-methyltransferase from the genome of the lignin-degrading fungus Phanerochaete chrysosporium for enhanced lignin degradation. Enzyme Microb Technol 2015; 82:66-73. [PMID: 26672450 DOI: 10.1016/j.enzmictec.2015.08.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 08/06/2015] [Accepted: 08/22/2015] [Indexed: 11/23/2022]
Abstract
Using bioinformatic homology search tools, this study utilized sequence phylogeny, gene organization and conserved motifs to identify members of the family of O-methyltransferases from lignin-degrading fungus Phanerochaete chrysosporium. The heterologous expression and characterization of O-methyltransferases from P. chrysosporium were studied. The expressed protein utilized S-(5'-adenosyl)-L-methionine p-toluenesulfonate salt (SAM) and methylated various free-hydroxyl phenolic compounds at both meta and para site. In the same motif, O-methyltransferases were also identified in other white-rot fungi including Bjerkandera adusta, Ceriporiopsis (Gelatoporia) subvermispora B, and Trametes versicolor. As free-hydroxyl phenolic compounds have been known as inhibitors for lignin peroxidase, the presence of O-methyltransferases in white-rot fungi suggested their biological functions in accelerating lignin degradation in white-rot basidiomycetes by converting those inhibitory groups into non-toxic methylated phenolic ones.
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Kirita M, Tanaka Y, Tagashira M, Kanda T, Maeda-Yamamoto M. Cloning and characterization of a novel O-methyltransferase from Flammulina velutipes that catalyzes methylation of pyrocatechol and pyrogallol structures in polyphenols. Biosci Biotechnol Biochem 2015; 79:1111-8. [DOI: 10.1080/09168451.2015.1015955] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Abstract
A novel O-methyltransferase gene was isolated from Flammulina velutipes. The isolated full-length cDNA was composed of a 690-nucleotide open reading frame encoding 230 amino acids. A database search revealed that the deduced amino acid sequence was similar to those of other O-methyltransferases; the highest identity was only 61.8% with Laccaria bicolor. The recombinant enzyme was expressed by Escherichia coli. BL21 (DE3) was assessed for its ability to methylate (−)-epigallocatechin-3-O-gallate (EGCG). LC–TOF–MS and NMR revealed that the enzyme produced five kinds of O-methylated EGCGs: (−)-epigallocatechin-3-O-(3-O-methyl)gallate, (−)-epigallocatechin-3-O-(4-O-methyl)gallate, (−)-epigallocatechin-3-O-(3,4-O-dimethyl)gallate, (−)-epigallocatechin-3-O-(3,5-O-dimethyl)gallate, and (−)-4′-O-methylepigallocatechin-3-O-(3,5-O-dimethyl)gallate. The substrate specificity of the enzyme for 20 kinds of polyphenols was assessed using the crude recombinant enzyme of O-methyltransferase. This enzyme introduced methyl group(s) into polyphenols with pyrocatechol and pyrogallol structures.
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Affiliation(s)
- Masanobu Kirita
- Research & Development-Production Headquarters, Asahi Breweries Limited, Moriya-shi, Ibaraki, Japan
| | - Yoshihisa Tanaka
- Research & Development-Production Headquarters, Asahi Breweries Limited, Moriya-shi, Ibaraki, Japan
| | - Motoyuki Tagashira
- Research & Development-Production Headquarters, Asahi Breweries Limited, Moriya-shi, Ibaraki, Japan
| | - Tomomasa Kanda
- Research & Development-Production Headquarters, Asahi Breweries Limited, Moriya-shi, Ibaraki, Japan
| | - Mari Maeda-Yamamoto
- National Food Research Institute, National Agriculture and Food Research Organization, Tsukuba-shi, Ibaraki, Japan
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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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Wang J, Yamada Y, Notake A, Todoroki Y, Tokumoto T, Dong J, Thomas P, Hirai H, Kawagishi H. Metabolism of bisphenol A by hyper lignin-degrading fungus Phanerochaete sordida YK-624 under non-ligninolytic condition. CHEMOSPHERE 2014; 109:128-133. [PMID: 24582362 DOI: 10.1016/j.chemosphere.2014.01.029] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 01/07/2014] [Accepted: 01/12/2014] [Indexed: 06/03/2023]
Abstract
Recently, we reported the conversion of bisphenol A (BPA) to 4-(2-(4-hydroxyphenyl)propan-2-yl)benzene-1,2-diol (hydroxy-BPA) by hyper lignin-degrading fungus Phanerochaete sordida YK-624 under non-ligninolytic condition. In the present study, the metabolism of hydroxy-BPA by P. sordida YK-624 was demonstrated under non-ligninolytic condition. Under these conditions, approximately 66% of hydroxy-BPA was degraded after 7 d of incubation. High-resolution electrospray ionization mass spectra and nuclear magnetic resonance analyses of the metabolites isolated from the culture broth indicated that hydroxy-BPA was metabolized to 4-(2-(4-hydroxyphenyl)propan-2-yl)-2-methoxyphenol (methoxy-BPA) and to 4-(2-(3,4-dimethoxyphenyl)propan-2-yl)phenol (dimethoxy-BPA) by sequential methylation events. These metabolites showed reduced estrogenic activity compared to BPA. These results suggested that the hydroxy BPA is methylated to two low toxic-methylation metabolites.
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Affiliation(s)
- Jianqiao Wang
- Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Yuto Yamada
- Graduate School of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Akira Notake
- Graduate School of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Yasushi Todoroki
- Graduate School of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan; Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Toshinobu Tokumoto
- Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Jing Dong
- Marine Science Institute, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX 78373, USA
| | - Peter Thomas
- Marine Science Institute, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX 78373, USA
| | - Hirofumi Hirai
- Graduate School of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan; Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan.
| | - Hirokazu Kawagishi
- Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan; Graduate School of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan; Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
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Kirita M, Tanaka Y, Tagashira M, Kanda T, Maeda-Yamamoto M. Purification and characterization of a novel O-methyltransferase from Flammulina velutipes. Biosci Biotechnol Biochem 2014; 78:806-11. [DOI: 10.1080/09168451.2014.912117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Abstract
An enzyme catalyzing the methylation of phenolic hydroxyl groups in polyphenols was identified from mycelial cultures of edible mushrooms to synthesize O-methylated polyphenols. Enzyme activity was measured to assess whether methyl groups were introduced into (−)-epigallocatechin-3-O-gallate (EGCG) using SAM as a methyl donor, and (−)-epigallocatechin-3-O-(3-O-methyl)-gallate (EGCG3″Me), (−)-epigallocatechin-3-O-(4-O-methyl)-gallate (EGCG4″Me), and (−)-epigallocatechin-3-O-(3,5-O-dimethyl)-gallate (EGCG3″,5″diMe) peaks were detected using crude enzyme preparations from mycelial cultures of Flammulina velutipes. The enzyme was purified using chromatographic and two-dimensional electrophoresis. The purified enzyme was subsequently analyzed on the basis of the partial amino acid sequence using LC–MS/MS. Partial amino acid sequencing identified the 17 and 12 amino acid sequences, VLEVGTLGGYSTTWLAR and TGGIIIVDNVVR. In database searches, these sequences showed high identity with O-methyltransferases from other mushroom species and completely matched 11 of 17 and 9 of 12 amino acids from five other mushroom O-methyltransferases.
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Affiliation(s)
- Masanobu Kirita
- Research & Development-Production Headquarters, Asahi Breweries Limited, Moriya-shi, Japan
| | - Yoshihisa Tanaka
- Research & Development-Production Headquarters, Asahi Breweries Limited, Moriya-shi, Japan
| | - Motoyuki Tagashira
- Research & Development-Production Headquarters, Asahi Breweries Limited, Moriya-shi, Japan
| | - Tomomasa Kanda
- Research & Development-Production Headquarters, Asahi Breweries Limited, Moriya-shi, Japan
| | - Mari Maeda-Yamamoto
- National Food Research Institute, National Agriculture and Food Research Organization, Tsukuba-shi, Japan
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Singh D, Zeng J, Chen S. Increasing manganese peroxidase productivity of Phanerochaete chrysosporium by optimizing carbon sources and supplementing small molecules. Lett Appl Microbiol 2011; 53:120-3. [DOI: 10.1111/j.1472-765x.2011.03070.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Jensen KA, Evans KM, Kirk TK, Hammel KE. Biosynthetic Pathway for Veratryl Alcohol in the Ligninolytic Fungus Phanerochaete chrysosporium. Appl Environ Microbiol 2010; 60:709-14. [PMID: 16349197 PMCID: PMC201370 DOI: 10.1128/aem.60.2.709-714.1994] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Veratryl alcohol (VA) is a secondary metabolite of white-rot fungi that produce the ligninolytic enzyme lignin peroxidase. VA stabilizes lignin peroxidase, promotes the ability of this enzyme to oxidize a variety of physiological substrates, and is accordingly thought to play a significant role in fungal ligninolysis. Pulse-labeling and isotope-trapping experiments have now clarified the pathway for VA biosynthesis in the white-rot basidiomycete Phanerochaete chrysosporium. The pulse-labeling data, obtained with C-labeled phenylalanine, cinnamic acid, benzoic acid, and benzaldehyde, showed that radiocarbon labeling followed a reproducible sequence: it peaked first in cinnamate, then in benzoate and benzaldehyde, and finally in VA. Phenylalanine, cinnamate, benzoate, and benzaldehyde were all efficient precursors of VA in vivo. The isotope-trapping experiments showed that exogenous, unlabeled benzoate and benzaldehyde were effective traps of phenylalanine-derived C. These results support a pathway in which VA biosynthesis proceeds as follows: phenylalanine --> cinnamate --> benzoate and/or benzaldehyde --> VA.
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Affiliation(s)
- K A Jensen
- Forest Products Laboratory, U.S. Department of Agriculture, Madison, Wisconsin 53705
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Chen H, Cai YB, Zhang WJ, Li W. Methoxylation pathway in biodesulfurization of model organosulfur compounds with Mycobacterium sp. BIORESOURCE TECHNOLOGY 2009; 100:2085-2087. [PMID: 19028092 DOI: 10.1016/j.biortech.2008.10.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 10/09/2008] [Accepted: 10/12/2008] [Indexed: 05/27/2023]
Abstract
A metabolic pathway for the biodesulfurization of model organosulfur compounds e.g., dibenzothiophene (DBT), is proposed. This pathway, defined as extended 4S pathway, incorporates the traditional 4S pathway with the methoxylation pathway from 2-hydroxybiphenyl (HBP) to 2-methoxybiphenyl (2-MBP). The formation of 2-MBP was confirmed by the gas chromatography-mass spectrometry (GC-MS) analysis. A similar pathway was also obtained in the desulfurization of 4,6-dimethyldibenzothiophene (4,6-DMDBT), confirming the methoxylation reaction in the desulfurization process by the Mycobacterium sp. strain. Compared with 2-HBP, 2-MBP has much slighter inhibition effect on the cell growth and desulfurization activity. Thus, the methoxylation pathway from 2-HBP to 2-MBP would make less inhibitory effect on the microbe. The new pathway with 2-MBP as the end product may be an alternative for the further desulfuration of the fossil fuels.
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Affiliation(s)
- Han Chen
- Department of Environmental Engineering, Zhejiang University (Yuquan Campus), Hangzhou 310027, China
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Beck H. Biosynthetic pathway for halogenated methoxybenzaldehydes in the white rot fungus Bjerkandera adusta. FEMS Microbiol Lett 2006. [DOI: 10.1111/j.1574-6968.1997.tb10334.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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Coque JJR, Alvarez-Rodríguez ML, Larriba G. Characterization of an inducible chlorophenol O-methyltransferase from Trichoderma longibrachiatum involved in the formation of chloroanisoles and determination of its role in cork taint of wines. Appl Environ Microbiol 2003; 69:5089-95. [PMID: 12957890 PMCID: PMC194934 DOI: 10.1128/aem.69.9.5089-5095.2003] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A novel S-adenosyl-L-methionine (SAM)-dependent methyltransferase catalyzing the O methylation of several chlorophenols and other halogenated phenols was purified 220-fold to apparent homogeneity from mycelia of Trichoderma longibrachiatum CECT 20431. The enzyme could be identified in partially purified protein preparations by direct photolabeling with [methyl-(3)H]SAM, and this reaction was prevented by previous incubation with S-adenosylhomocysteine. Gel filtration indicated that the M(r) was 112,000, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the enzyme was composed of two subunits with molecular weights of approximately 52,500. The enzyme had a pH optimum between 8.2 and 8.5 and an optimum temperature of 28 degrees C, with a pI of 4.9. The K(m) values for 2,4,6-trichlorophenol and SAM were 135.9 +/- 12.8 and 284.1 +/- 35.1 micro M, respectively. S-Adenosylhomocysteine acted as a competitive inhibitor, with a K(i) of 378.9 +/- 45.4 micro M. The methyltransferase was also strongly inhibited by low concentrations of several metal ions, such as Cu(2+), Hg(2+), Zn(2+), and Ag(+), and to a lesser extent by p-chloromercuribenzoic acid, but it was not significantly affected by several thiols or other thiol reagents. The methyltransferase was specifically induced by several chlorophenols, especially if they contained three or more chlorine atoms in their structures. Substrate specificity studies showed that the activity was also specific for halogenated phenols containing fluoro, chloro, or bromo substituents, whereas other hydroxylated compounds, such as hydroxylated benzoic acids, hydroxybenzaldehydes, phenol, 2-metoxyphenol, and dihydroxybenzene, were not methylated.
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Affiliation(s)
- Juan-José R Coque
- Departamento de Microbiología, Facultad de Ciencias, Universidad de Extremadura, 06071 Badajoz, Spain.
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Liu, Benedict, Stipanovic, Bell. Purification and Characterization of S-Adenosyl-L-Methionine: Desoxyhemigossypol-6-O-Methyltransferase from Cotton Plants. An Enzyme Capable of Methylating the Defense Terpenoids of Cotton. PLANT PHYSIOLOGY 1999; 121:1017-1024. [PMID: 10557251 PMCID: PMC59466 DOI: 10.1104/pp.121.3.1017] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/1999] [Accepted: 07/12/1999] [Indexed: 05/23/2023]
Abstract
Cotton contains a unique group of terpenoids including desoxyhemigossypol, hemigossypol, gossypol, hemigossypolone, and the heliocides that are part of the plant's defense system against pathogenic fungi and insects. Desoxyhemigossypol is a key intermediate in the biosynthesis of these compounds. We have isolated, purified, and characterized from cotton stele tissue infected with Verticillium dahliae a methyltransferase (S-adenosyl-L-Met: desoxyhemigossypol-6-O-methyltransferase) that specifically methylates the 6-position of desoxyhemigossypol to form desoxyhemigossypol-6-methyl ether with a K(m) value of 4.5 µM for desoxyhemigossypol and a K(cat)/K(m) of 5.08 x 10(4) s(-1) (mol/L)(-1). The molecular mass of the native enzyme is 81.4 kD and is dissociated into two subunits of 41.2 kD on sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels. The enzymatic reaction does not require Mg(+2) and is inhibited 98% with 10 mM p-chloromercuribenzoate. Desoxyhemigossypol-6-methyl ether leads to the biosynthesis of methylated hemigossypol, gossypol, hemigossypolone, and the heliocides, which lowers their effectiveness as phytoalexins and insecticides.
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Affiliation(s)
- Liu
- United States Department of Agriculture, Agricultural Research Service, Southern Crops Research Laboratory, College Station, Texas 77843
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Chloromethane production by wood-rotting fungi and an estimate of the global flux to the atmosphere. ACTA ACUST UNITED AC 1998. [DOI: 10.1017/s0953756298006157] [Citation(s) in RCA: 101] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Jeffers MR, McRoberts WC, Harper DB. Identification of a phenolic 3-O-methyltransferase in the lignin-degrading fungus Phanerochaete chrysosporium. MICROBIOLOGY (READING, ENGLAND) 1997; 143 ( Pt 6):1975-1981. [PMID: 9202473 DOI: 10.1099/00221287-143-6-1975] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A methyltransferase enzyme catalysing the 3-O-methylation of isovanillic acid (3-hydroxy-4-methoxybenzoic acid) by S-adenosylmethionine (SAM) was identified in Phanerochaete chrysosporium and purified. Gel filtration indicated an M(r) of 71,000 and SDS-PAGE showed that the enzyme was composed of two subunits of M(r) approximately 36,000. Substrate utilization studies demonstrated that the enzyme was highly specific, displaying an exclusive preference for the methylation of the 3-hydroxyl group of several substituted benzoic acids. 3-Hydroxybenzoic acids with a methoxyl or hydroxyl substituent in the 2 or 4 position were the best substrates with isovanillic and 3,4-dihydroxybenzoic acids showing the highest rates of methylation. The 3-O-methyltransferase enzyme was induced later in the growth cycle than the 4-O-methyltransferase previously isolated from this fungus, which is believed to have a role in the 4-O-methylation of lignin degradation products. However the function of this meta-specific enzyme, the first phenolic 3-O-methyltransferase isolated from a fungus, remains unclear. The combined activities of the 3- and 4-O-methyltransferase enzymes satisfactorily account for the pattern of SAM-dependent methylating activity shown by whole mycelia to phenolic substrates.
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Affiliation(s)
- Maurice R Jeffers
- Microbial Biochemistry Section, Department of Food Science, The Queen's University of Belfast, Newforge Lane, Belfast BT9 5PX, UK
| | - W Colin McRoberts
- Food Science Division, Department of Agriculture for Northern Ireland, Newforge Lane, Belfast BT9 5PX, UK
| | - David B Harper
- Microbial Biochemistry Section, Department of Food Science, The Queen's University of Belfast, Newforge Lane, Belfast BT9 5PX, UK
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Harper DB, McRoberts WC, Kennedy JT. Comparison of the Efficacies of Chloromethane, Methionine, and S-Adenosylmethionine as Methyl Precursors in the Biosynthesis of Veratryl Alcohol and Related Compounds in Phanerochaete chrysosporium. Appl Environ Microbiol 1996; 62:3366-70. [PMID: 16535404 PMCID: PMC1388942 DOI: 10.1128/aem.62.9.3366-3370.1996] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The effect on veratryl alcohol production of supplementing cultures of the lignin-degrading fungus Phanerochaete chrysosporium with different methyl-(sup2)H(inf3)-labelled methyl precursors has been investigated. Both chloromethane (CH(inf3)Cl) and l-methionine caused earlier initiation of veratryl alcohol biosynthesis, but S-adenosyl-l-methionine (SAM) retarded the formation of the compound. A high level of C(sup2)H(inf3) incorporation into both the 3- and 4-O-methyl groups of veratryl alcohol occurred when either l-[methyl-(sup2)H(inf3)]methionine or C(sup2)H(inf3)Cl was present, but no significant labelling was detected when S-adenosyl-l-[methyl-(sup2)H(inf3)]methionine was added. Incorporation of C(sup2)H(inf3) from C(sup2)H(inf3)Cl was strongly antagonized by the presence of unlabelled l-methionine; conversely, incorporation of C(sup2)H(inf3) from l-[methyl-(sup2)H(inf3)]methionine was reduced by CH(inf3)Cl. These results suggest that l-methionine is converted either directly or via an intermediate to CH(inf3)Cl, which is utilized as a methyl donor in veratryl alcohol biosynthesis. SAM is not an intermediate in the conversion of l-methionine to CH(inf3)Cl. In an attempt to identify the substrates for O methylation in the metabolic transformation of benzoic acid to veratryl alcohol, the relative activities of the SAM- and CH(inf3)Cl-dependent methylating systems on several possible intermediates were compared in whole mycelia by using isotopic techniques. 4-Hydroxybenzoic acid was a much better substrate for the CH(inf3)Cl-dependent methylation system than for the SAM-dependent system. The CH(inf3)Cl-dependent system also had significantly increased activities toward both isovanillic acid and vanillyl alcohol compared with the SAM-dependent system. On the basis of these results, it is proposed that the conversion of benzoic acid to veratryl alcohol involves para hydroxylation, methylation of 4-hydroxybenzoic acid, meta hydroxylation of 4-methoxybenzoic acid to form isovanillic acid, and methylation of isovanillic acid to yield veratric acid.
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Biosynthesis and metabolic role of chloromethane in fungi. ACTA ACUST UNITED AC 1995. [DOI: 10.1007/978-94-011-0061-8_21] [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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Barr DP, Aust SD. Pollutant degradation by white rot fungi. REVIEWS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 1994; 138:49-72. [PMID: 7938784 DOI: 10.1007/978-1-4612-2672-7_3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The white rot fungi technology is very different from other more well-established methods of bioremediation (e.g., bacterial systems). The differences are primarily due to the mechanisms discussed previously. The unusual mechanisms used by the fungi provide them with several advantages for pollutant degradation, but the complexity of these mechanisms has also made the technology slow to emerge as a viable method of bioremediation. One distinct advantage that white rot fungi have over bacterial systems is that they do not require preconditioning to a particular pollutant. Bacteria must be preexposed to a pollutant to allow the enzymes that degrade the pollutant to be induced. The pollutant must also be present in a significant concentration, otherwise induction of enzyme synthesis will not occur. Therefore, there is a finite level to which pollutants can be degraded by bacteria. In contrast, the degradative enzymes of white rot fungi are induced by nutrient limitation. Thus, cultivate the fungus on a nutrient that is limited in something, and the degradative process will be initiated. Also, because the induction of the lignin-degrading system is not dependent on the chemical, pollutants are degraded to near-nondetectable levels by white rot fungi. Another unique feature of pollutant degradation by white rot fungi involves kinetics. The process of chemical conversion by these fungi occurs via a free-radical process, and thus the degradation of chemicals often follows pseudo-first-order kinetics. In fact, in several studies, it has been found that the rate of mineralization or disappearance of a pollutant is proportional to the concentration of the pollutant. This makes the time required to achieve decontamination more important than the rate of degradation. Because the metabolism of chemicals by bacteria involves mostly enzymatic conversions, pollutant degradation often follows Michaelis-Menton-type kinetics. Therefore, Km values of various degradative enzymes with respect to the pollutant must be considered when using bacteria for bioremediation. Considering this, the solubility of a pollutant or a mixture of pollutants might also present a problem for bacterial degradation. In contrast, using a nonspecific free-radical-based mechanism, the fungi are able to degrade insoluble complex mixtures of pollutants, such as creosote (Aust and Bumpus 1989) and Arochlor (Bumpus and Aust 1987b). Inexpensive nutrient sources, such as sawdust, wood chips, surplus grains, and agricultural wastes, can be used to effectively cultivate white rot fungi.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- D P Barr
- Biotechnology Center, Utah State University, Logan 84322-4705
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Coulter C, Hamilton JT, Harper DB. Evidence for the existence of independent chloromethane- and S-adenosylmethionine-utilizing systems for methylation in Phanerochaete chrysosporium. Appl Environ Microbiol 1993; 59:1461-6. [PMID: 8517739 PMCID: PMC182104 DOI: 10.1128/aem.59.5.1461-1466.1993] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
O methylation of acetovanillone at 4 position by C2H3Cl and S-adenosyl[methyl-2H3]methionine was monitored in whole mycelia of Phanerochaete chrysosporium in the presence and absence of S-adenosylhomocysteine. Both the amount of the methylation product, 3,4-dimethoxyacetophenone, and the percent C2H3 incorporation into the 4-methoxyl group of the compound were determined. The results strongly suggest the presence of biochemically distinct systems for O methylation of acetovanillone utilizing S-adenosylmethionine and chloromethane, respectively, as the methyl donor. The S-adenosylmethionine-dependent enzyme is induced early in the growth cycle, with activity attaining an initial maximum after 55 h of incubation. Methylation by this enzyme is totally suppressed by 1 mM S-adenosylhomocysteine over almost the entire growth cycle. S-Adenosylmethionine-dependent O-methyltransferase activity is detectable in cell extracts, and the purification and characterization of the enzyme are described elsewhere (C. Coulter, J. T. Kennedy, W. C. McRoberts, and D. B. Harper, Appl. Environ. Microbiol. 59:706-711, 1993). The chloromethane-utilizing methylation system is absent in early growth but attains peak activity in the mid-growth phase after 72 h of incubation. The system is not significantly inhibited by S-adenosylhomocysteine at any stage of growth. No chloromethane-dependent O-methyltransferase activity is detectable in cell extract, suggesting that the enzyme is membrane bound and/or part of a multienzyme complex. Although the biochemical role of the chloromethane-dependent methylation system in metabolism is not known, one possible function could be the regeneration of veratryl alcohol degraded by the attack of lignin peroxidase.
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Affiliation(s)
- C Coulter
- Department of Food Science, Queen's University of Belfast, United Kingdom
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