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Huang X, Liu X, Xue Y, Pan B, Xiao L, Wang S, Lever MA, Hinrichs KU, Inagaki F, Liu C. Methane Production by Facultative Anaerobic Wood-Rot Fungi via a New Halomethane-Dependent Pathway. Microbiol Spectr 2022; 10:e0170022. [PMID: 36102652 PMCID: PMC9604129 DOI: 10.1128/spectrum.01700-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 08/26/2022] [Indexed: 12/31/2022] Open
Abstract
The greenhouse gas methane (CH4) is of pivotal importance for Earth's climate system and as a human energy source. A significant fraction of this CH4 is produced by anaerobic Archaea. Here, we describe the first CH4 production by facultative anaerobic wood-rot fungi during growth on hydroxylated/carboxylated aromatic compounds, including lignin and lignite. The amount of CH4 produced by fungi is positively correlated with the amount of CH3Cl produced during the rapid growth period of the fungus. Biochemical, genetic, and stable isotopic tracer analyses reveal the existence of a novel halomethane-dependent fungal CH4 production pathway during the degradation of phenol and benzoic acid monomers and polymers and utilization of cyclic sugars. Even though this halomethane-dependent pathway may only play a side role in anaerobic fungal activity, it could represent a globally significant, previously overlooked source of biogenic CH4 in natural ecosystems. IMPORTANCE Here, we demonstrate that wood-rot fungi produce methane anaerobically without the involvement of methanogenic archaea via a new, halomethane-dependent pathway. These findings of an anaerobic fungal methane formation pathway open another avenue in methane research and will further assist with current efforts in the identification of the processes involved and their ecological implications.
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Affiliation(s)
- Xin Huang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Xuan Liu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Yarong Xue
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Bingcai Pan
- State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing, Jiangsu, China
| | - Lei Xiao
- School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou, Jiangsu, China
| | - Shuijuan Wang
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu, China
| | - Mark A. Lever
- Department of Environmental Systems Science, ETH Zürich, Institute of Biogeochemistry and Pollutant Dynamics, Zürich, Switzerland
| | - Kai-Uwe Hinrichs
- MARUM Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | - Fumio Inagaki
- Mantle Drilling Promotion Office, Institute for Marine-Earth Exploration and Engineering (MarE3), Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokohama, Japan
- Department of Earth Sciences, Graduate School of Science, Tohoku University, Sendai, Japan
| | - Changhong Liu
- State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, Jiangsu, China
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Kowalczyk JE, Peng M, Pawlowski M, Lipzen A, Ng V, Singan V, Wang M, Grigoriev IV, Mäkelä MR. The White-Rot Basidiomycete Dichomitus squalens Shows Highly Specific Transcriptional Response to Lignocellulose-Related Aromatic Compounds. Front Bioeng Biotechnol 2019; 7:229. [PMID: 31616664 PMCID: PMC6763618 DOI: 10.3389/fbioe.2019.00229] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 09/05/2019] [Indexed: 11/13/2022] Open
Abstract
Lignocellulosic plant biomass is an important feedstock for bio-based economy. In particular, it is an abundant renewable source of aromatic compounds, which are present as part of lignin, as side-groups of xylan and pectin, and in other forms, such as tannins. As filamentous fungi are the main organisms that modify and degrade lignocellulose, they have developed a versatile metabolism to convert the aromatic compounds that are toxic at relatively low concentrations to less toxic ones. During this process, fungi form metabolites some of which represent high-value platform chemicals or important chemical building blocks, such as benzoic, vanillic, and protocatechuic acid. Especially basidiomycete white-rot fungi with unique ability to degrade the recalcitrant lignin polymer are expected to perform highly efficient enzymatic conversions of aromatic compounds, thus having huge potential for biotechnological exploitation. However, the aromatic metabolism of basidiomycete fungi is poorly studied and knowledge on them is based on the combined results of studies in variety of species, leaving the overall picture in each organism unclear. Dichomitus squalens is an efficiently wood-degrading white-rot basidiomycete that produces a diverse set of extracellular enzymes targeted for lignocellulose degradation, including oxidative enzymes that act on lignin. Our recent study showed that several intra- and extracellular aromatic compounds were produced when D. squalens was cultivated on spruce wood, indicating also versatile aromatic metabolic abilities for this species. In order to provide the first molecular level systematic insight into the conversion of plant biomass derived aromatic compounds by basidiomycete fungi, we analyzed the transcriptomes of D. squalens when grown with 10 different lignocellulose-related aromatic monomers. Significant differences for example with respect to the expression of lignocellulose degradation related genes, but also putative genes encoding transporters and catabolic pathway genes were observed between the cultivations supplemented with the different aromatic compounds. The results demonstrate that the transcriptional response of D. squalens is highly dependent on the specific aromatic compounds present suggesting that instead of a common regulatory system, fine-tuned regulation is needed for aromatic metabolism.
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Affiliation(s)
| | - Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute and Fungal Molecular Physiology, Utrecht University, Utrecht, Netherlands
| | - Megan Pawlowski
- U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, United States
| | - Anna Lipzen
- U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, United States
| | - Vivian Ng
- U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, United States
| | - Vasanth Singan
- U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, United States
| | - Mei Wang
- U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, United States
| | - Igor V Grigoriev
- U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA, United States
| | - Miia R Mäkelä
- Department of Microbiology, University of Helsinki, Helsinki, Finland
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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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Lenhart K, Bunge M, Ratering S, Neu TR, Schüttmann I, Greule M, Kammann C, Schnell S, Müller C, Zorn H, Keppler F. Evidence for methane production by saprotrophic fungi. Nat Commun 2012; 3:1046. [DOI: 10.1038/ncomms2049] [Citation(s) in RCA: 127] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 08/02/2012] [Indexed: 11/09/2022] Open
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Degradation of Chloro-organic Pollutants by White Rot Fungi. ENVIRONMENTAL SCIENCE AND ENGINEERING 2012. [DOI: 10.1007/978-3-642-23789-8_2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Li M, Zhang C, Liu G, Zhang R, Luo Y, Li J. Power generation from veratryl alcohol and microbial community analysis in the microbial fuel cell. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2010; 45:1195-1206. [PMID: 20563913 DOI: 10.1080/10934529.2010.493780] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Veratryl alcohol (VA) is a product from the biodegradation of lignocellulosic biomass. The objective of this study was to explore the possibility whether VA could be used as the fuel of the microbial fuel cell (MFC) to generate power. Two types of MFCs, a two-chamber MFC and a single-chamber air-cathode MFC, were set up for experiments. In the two-chamber MFC, average maximum current outputs higher than 700 microA were obtained using various mixtures of glucose and VA as the fuel. The highest power density of 35.17 W m(-3) was achieved using the mixture of 1000 mg L(-1) glucose and 50 mg L(-1) VA as the fuel. With 500 mg L(-1) VA as the fuel in the MFC, we obtained an average maximum current output of 181 microA. In the single-chamber MFC, the maximum current output reached up to 178 microA with 500 mg L(-1) VA in the fed-batch mode and the maximum CE reached 23.77% with 100 mg L(-1) VA. At the end of all operation cycles of the MFCs, the glucose and VA were undetectable in the solution, and the removal efficiencies of COD were between 75% and 88%. The denaturing gradient gel electrophoresis profiles of 16S rRNA gene indicated that the dominant species on the anode biofilm did not change significantly with the different substrates, but the abundance of some species increased greatly. The scanning electron micrographs showed that the most abundant bacteria on the electrode were bacilli. The dominant species belonged to bacteroidetes and proteobacterium.
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Affiliation(s)
- Mingchen Li
- Sun Yat-sen University, Guangzhou, Guangdong, China
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Coulter C, Kennedy JT, McRoberts WC, Harper DB. Purification and Properties of an S-Adenosylmethionine: 2,4-Disubstituted Phenol O-Methyltransferase from Phanerochaete chrysosporium. Appl Environ Microbiol 2010; 59:706-11. [PMID: 16348886 PMCID: PMC202178 DOI: 10.1128/aem.59.3.706-711.1993] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An enzyme catalyzing the O-methylation of acetovanillone (3-methoxy-4-hydroxyacetophenone) by S-adeno-sylmethionine was isolated from Phanerochaete chrysosporium and purified 270-fold by ultrafiltration, anion-exchange chromatography, and gel filtration. The enzyme exhibited a pH optimum between 7 and 9 and was rapidly denatured at temperatures above 55 degrees C. The K(m) values for acetovanillone and S-adenosylmethionine were 34 and 99 muM, respectively. S-Adenosylhomocysteine acted as a powerful competitive inhibitor of S-adenosylmethionine, with a K(i) of 41 muM. The enzyme was also susceptible to inhibition by thiol reagents and low concentrations of heavy metal ions. Gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis indicated that the enzyme was monomeric and had a molecular weight of approximately 53,000. Substrate specificity studies showed that 3-methoxy- and 3,5-dimethoxy-substituted 4-hydroxy-benzaldehydes, -benzoic acids, and -acetophenones were the preferred substrates for the enzyme. The corresponding 3,4-dihydroxy compounds were methylated relatively slowly, while the 3-hydroxy-4-methoxy compounds were almost inactive as substrates. Substituents in both the 2 and 4 positions relative to the hydroxyl group appeared to be essential for significant enzyme attack of a substrate. Provided that certain steric criteria were satisfied, the nature of the substituent was not critical. Hence, xenobiotic compounds such as 2,4-dichlorophenol and 2,4-dibromophenol were methylated almost as readily as acetovanillone. However, an extended side chain in the 4 position was not compatible with activity as a substrate, and neither homovanillic, caffeic, nor ferulic acid was methylated. The substrate range of the O-methyltransferase tends to imply a role in the catabolism or detoxification of lignin degradation products such as vanillic and syringic acids.
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Affiliation(s)
- C Coulter
- Microbial and Fungal Biochemistry Section, Department of Food Science, The Queen's University of Belfast, Newforge Lane, Belfast BT9 5PX, United Kingdom
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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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10
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Saxena, Aouad, Attieh, Saini. Biochemical characterization of chloromethane emission from the wood-rotting fungus phellinus pomaceus. Appl Environ Microbiol 1998; 64:2831-5. [PMID: 9687437 PMCID: PMC106779 DOI: 10.1128/aem.64.8.2831-2835.1998] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/1997] [Accepted: 06/04/1998] [Indexed: 02/08/2023] Open
Abstract
Many wood-rotting fungi, including Phellinus pomaceus, produce chloromethane (CH3Cl). P. pomaceus can be cultured in undisturbed glucose mycological peptone liquid medium to produce high amounts of CH3Cl. The biosynthesis of CH3Cl is catalyzed by a methyl chloride transferase (MCT), which appears to be membrane bound. The enzyme is labile upon removal from its natural location and upon storage at low temperature in its bound state. Various detergents failed to solubilize the enzyme in active form, and hence it was characterized by using a membrane fraction. The enzyme had a sharp pH optimum between 7 and 7.2. Its apparent Km for Cl- (ca. 300 mM) was much higher than that for I- (250 &mgr;M) or Br- (11 mM). A comparison of these Km values to the relative in vivo methylation rates for different halides suggests that the real Km for Cl- may be much lower, but the calculated value is high because the CH3Cl produced is used immediately in a coupled reaction. Among various methyl donors tested, S-adenosyl-L-methionine (SAM) was the only one that supported significant methylation by MCT. The reaction was inhibited by S-adenosyl-L-homocysteine, an inhibitor of SAM-dependent methylation, suggesting that SAM is the natural methyl donor. These findings advance our comprehension of a poorly understood metabolic sector at the origin of biogenic emissions of halomethanes, which play an important role in atmospheric chemistry.
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Affiliation(s)
- Saxena
- Institut de Recherche en Biologie Vegetale, Universite de Montreal, Montreal, Quebec, Canada H1X 2B2
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11
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Rajarathnam S, Shashirekha MN, Bano Z. Biodegradative and biosynthetic capacities of mushrooms: present and future strategies. Crit Rev Biotechnol 1998; 18:91-236. [PMID: 9674114 DOI: 10.1080/0738-859891224220] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- S Rajarathnam
- Central Food Technological Research Institute, Mysore, India
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12
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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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13
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de Jong E, Field JA. Sulfur tuft and turkey tail: biosynthesis and biodegradation of organohalogens by Basidiomycetes. Annu Rev Microbiol 1997; 51:375-414. [PMID: 9343355 DOI: 10.1146/annurev.micro.51.1.375] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Chlorinated aliphatic and aromatic compounds are generally considered to be undesirable xenobiotic pollutants. However, the higher fungi, Basidiomycetes, have a widespread capacity for organohalogen biosynthesis. Adsorbable organic halogens (AOX) and/or low-molecular-weight halogenated compounds are produced by Basidiomycetes of 68 genera from 20 different families. Most of the 81 halogenated metabolites identified from Basidiomycetes to date are chlorinated, although brominated and iodated metabolites have also been described. Two broad categories of Basidiomycete organohalogen metabolites are the halogenated aromatic compounds and the haloaliphatic compounds. Some of these organohalogen metabolites have demonstrable physiological roles as antibiotics and as metabolites involved in lignin degradation. Basidiomycetes produce large amounts of low-molecular-weight organohalogens or adsorbable organic halogens (AOX) when grown on lignocellulosic substrates. In our view, Basidiomycetes, as decomposers of forest litter, are a major source of natural organohalogens in terrestrial environments. Basidiomycetes are also potent degraders of a wide range of chlorinated pollutants, such as bleachery effluent from kraft mills and pentachlorophenol, polychlorinated dioxins, and polychlorinated biphenyls. The extracellular, lignin-degrading enzymes of the Basidiomycetes are involved in the oxidative degradation of chlorophenols and dioxin and can cause reductive dechlorination of halomethanes. There is no clear-cut separation between "polluters" and "clean-uppers" within the Basidiomycetes. Several genera, e.g. Bjerkandera, Hericium, Phlebia, and Trametes, produce significant amounts of chlorinated compounds but are also highly effective in metabolizing or biotransforming chlorinated pollutants.
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Affiliation(s)
- E de Jong
- Department of Wood Science, The University of British Columbia, Vancouver, Canada.
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14
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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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Naturally Occuring Organohalogen Compounds — A Comprehensive Survery. FORTSCHRITTE DER CHEMIE ORGANISCHER NATURSTOFFE / PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS 1996. [DOI: 10.1007/978-3-7091-6887-5_1] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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Attieh JM, Hanson AD, Saini HS. Purification and characterization of a novel methyltransferase responsible for biosynthesis of halomethanes and methanethiol in Brassica oleracea. J Biol Chem 1995; 270:9250-7. [PMID: 7721844 DOI: 10.1074/jbc.270.16.9250] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
A novel S-adenosyl-L-methionine:halide/bisulfide methyltransferase (EC 2.1.1.-) was purified approximately 1000-fold to apparent homogeneity from leaves of Brassica oleracea. The enzyme catalyzed the S-adenosyl-L-methionine-dependent methylation of the halides iodide, bromide, and chloride to monohalomethanes and of bisulfide to methanethiol. The dual function of the enzyme was demonstrated through co-purification of the halide- and bisulfide-methylating activities in the same ratio and by studies of competition between the alternative substrates iodide and bisulfide. The purification procedure included gel filtration, anion exchange chromatography, and affinity chromatography on adenosine-agarose. Elution of the protein from a chromatofocusing column indicated a pI value of 4.8. The pH optimum of halide methylation (5.5-7.0) was different from that of bisulfide methylation (7.0-8.0). The molecular mass values for the native and denatured protein were 29.5 and 28 kDa, respectively, suggesting that the active enzyme is a monomer. The enzyme had the highest specificity constant for iodide and the next highest for bisulfide. Substrate interaction kinetics and product inhibition patterns were consistent with an Ordered Bi Bi mechanism.
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Affiliation(s)
- J M Attieh
- Institut de recherche en biologie végétale, Université de Montréal, Québec, Canada
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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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Spinnler HE, de Jong E, Mauvais G, Semon E, le Quere JL. Production of halogenated compounds byBjerkandera adusta. Appl Microbiol Biotechnol 1994. [DOI: 10.1007/bf00902719] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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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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