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Witte T, Hicks C, Hermans A, Shields S, Overy DP. Debunking the Myth of Fusarium poae T-2/HT-2 Toxin Production. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:3949-3957. [PMID: 38375818 PMCID: PMC10905990 DOI: 10.1021/acs.jafc.3c08437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 02/02/2024] [Accepted: 02/02/2024] [Indexed: 02/21/2024]
Abstract
Fusarium poae is commonly detected in field surveys of Fusarium head blight (FHB) of cereal crops and can produce a range of trichothecene mycotoxins. Although experimentally validated reports of F. poae strains producing T-2/HT-2 trichothecenes are rare, F. poae is frequently generalized in the literature as a producer of T-2/HT-2 toxins due to a single study from 2004 in which T-2/HT-2 toxins were detected at low levels from six out of forty-nine F. poae strains examined. To validate/substantiate the observations reported from the 2004 study, the producing strains were acquired and phylogenetically confirmed to be correctly assigned as F. poae; however, no evidence of T-2/HT-2 toxin production was observed from axenic cultures. Moreover, no evidence for a TRI16 ortholog, encoding a key acyltransferase shown to be necessary for T-2 toxin production in other Fusarium species, was observed in any of the de novo assembled genomes of the F. poae strains. Our findings corroborate multiple field-based and in vitro studies on FHB-associated Fusarium populations which also do not support the production of T-2/HT-2 toxins with F. poae and therefore conclude that F. poae should not be generalized as a T-2/HT-2 toxin producing species of Fusarium.
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Affiliation(s)
- Thomas
E. Witte
- Agriculture
and Agri-Food Canada, Ottawa Research and
Development Centre, Ottawa, Ontario K1A 0C6, Canada
- Department
of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Carmen Hicks
- Agriculture
and Agri-Food Canada, Ottawa Research and
Development Centre, Ottawa, Ontario K1A 0C6, Canada
| | - Anne Hermans
- Agriculture
and Agri-Food Canada, Ottawa Research and
Development Centre, Ottawa, Ontario K1A 0C6, Canada
| | - Sam Shields
- Agriculture
and Agri-Food Canada, Ottawa Research and
Development Centre, Ottawa, Ontario K1A 0C6, Canada
| | - David P. Overy
- Agriculture
and Agri-Food Canada, Ottawa Research and
Development Centre, Ottawa, Ontario K1A 0C6, Canada
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Davis KA, Jones AM, Panaccione DG. Two Satellite Gene Clusters Enhance Ergot Alkaloid Biosynthesis Capacity of Aspergillus leporis. Appl Environ Microbiol 2023; 89:e0079323. [PMID: 37432119 PMCID: PMC10467348 DOI: 10.1128/aem.00793-23] [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: 05/11/2023] [Accepted: 06/25/2023] [Indexed: 07/12/2023] Open
Abstract
Ergot alkaloids are fungal specialized metabolites that are important in agriculture and serve as sources of several pharmaceuticals. Aspergillus leporis is a soil saprotroph that possesses two ergot alkaloid biosynthetic gene clusters encoding lysergic acid amide production. We identified two additional, partial biosynthetic gene clusters within the A. leporis genome containing some of the ergot alkaloid synthesis (eas) genes required to make two groups of clavine ergot alkaloids, fumigaclavines and rugulovasines. Clavines possess unique biological properties compared to lysergic acid derivatives. Bioinformatic analyses indicated the fumigaclavine cluster contained functional copies of easA, easG, easD, easM, and easN. Genes resembling easQ and easH, which are required for rugulovasine production, were identified in a separate gene cluster. The pathways encoded by these partial, or satellite, clusters would require intermediates from the previously described lysergic acid amide pathway to synthesize a product. Chemical analyses of A. leporis cultures revealed the presence of fumigaclavine A. However, rugulovasine was only detected in a single sample, prompting a heterologous expression approach to confirm functionality of easQ and easH. An easA knockout strain of Metarhizium brunneum, which accumulates the rugulovasine precursor chanoclavine-I aldehyde, was chosen as expression host. Strains of M. brunneum expressing easQ and easH from A. leporis accumulated rugulovasine as demonstrated through mass spectrometry analysis. These data indicate that A. leporis is exceptional among fungi in having the capacity to synthesize products from three branches of the ergot alkaloid pathway and for utilizing an unusual satellite cluster approach to achieve that outcome. IMPORTANCE Ergot alkaloids are chemicals produced by several species of fungi and are notable for their impacts on agriculture and medicine. The ability to make ergot alkaloids is typically encoded by a clustered set of genes that are physically adjacent on a chromosome. Different ergot alkaloid classes are formed via branching of a complex pathway that begins with a core set of the same five genes. Most ergot alkaloid-producing fungi have a single cluster of genes that is complete, or self-sufficient, and produce ergot alkaloids from one or occasionally two branches from that single cluster. Our data show that Aspergillus leporis is exceptional in having the genetic capacity to make products from three pathway branches. Moreover, it uses a satellite cluster approach, in which gene products of partial clusters rely on supplementation with a chemical intermediate produced via another gene cluster, to diversify its biosynthetic potential without duplicating all the steps.
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Affiliation(s)
- Kyle A. Davis
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, West Virginia, USA
| | - Abigail M. Jones
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, West Virginia, USA
| | - Daniel G. Panaccione
- Division of Plant and Soil Sciences, West Virginia University, Morgantown, West Virginia, USA
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Meneely J, Greer B, Kolawole O, Elliott C. T-2 and HT-2 Toxins: Toxicity, Occurrence and Analysis: A Review. Toxins (Basel) 2023; 15:481. [PMID: 37624238 PMCID: PMC10467144 DOI: 10.3390/toxins15080481] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 07/11/2023] [Accepted: 07/27/2023] [Indexed: 08/26/2023] Open
Abstract
One of the major classes of mycotoxins posing serious hazards to humans and animals and potentially causing severe economic impact to the cereal industry are the trichothecenes, produced by many fungal genera. As such, indicative limits for the sum of T-2 and HT-2 were introduced in the European Union in 2013 and discussions are ongoing as to the establishment of maximum levels. This review provides a concise assessment of the existing understanding concerning the toxicological effects of T-2 and HT-2 in humans and animals, their biosynthetic pathways, occurrence, impact of climate change on their production and an evaluation of the analytical methods applied to their detection. This study highlights that the ecology of F. sporotrichioides and F. langsethiae as well as the influence of interacting environmental factors on their growth and activation of biosynthetic genes are still not fully understood. Predictive models of Fusarium growth and subsequent mycotoxin production would be beneficial in predicting the risk of contamination and thus aid early mitigation. With the likelihood of regulatory maximum limits being introduced, increased surveillance using rapid, on-site tests in addition to confirmatory methods will be required. allowing the industry to be proactive rather than reactive.
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Affiliation(s)
- Julie Meneely
- Institute for Global Food Security, National Measurement Laboratory: Centre of Excellence in Agriculture and Food Integrity, Queen’s University Belfast, 19 Chlorine Gardens, Belfast BT9 5DL, UK; (B.G.); (O.K.); (C.E.)
- The International Joint Research Center on Food Security (IJC-FOODSEC), 113 Thailand Science Park, Pahonyothin Road, Khong Luang 12120, Thailand
| | - Brett Greer
- Institute for Global Food Security, National Measurement Laboratory: Centre of Excellence in Agriculture and Food Integrity, Queen’s University Belfast, 19 Chlorine Gardens, Belfast BT9 5DL, UK; (B.G.); (O.K.); (C.E.)
- The International Joint Research Center on Food Security (IJC-FOODSEC), 113 Thailand Science Park, Pahonyothin Road, Khong Luang 12120, Thailand
| | - Oluwatobi Kolawole
- Institute for Global Food Security, National Measurement Laboratory: Centre of Excellence in Agriculture and Food Integrity, Queen’s University Belfast, 19 Chlorine Gardens, Belfast BT9 5DL, UK; (B.G.); (O.K.); (C.E.)
- The International Joint Research Center on Food Security (IJC-FOODSEC), 113 Thailand Science Park, Pahonyothin Road, Khong Luang 12120, Thailand
| | - Christopher Elliott
- Institute for Global Food Security, National Measurement Laboratory: Centre of Excellence in Agriculture and Food Integrity, Queen’s University Belfast, 19 Chlorine Gardens, Belfast BT9 5DL, UK; (B.G.); (O.K.); (C.E.)
- The International Joint Research Center on Food Security (IJC-FOODSEC), 113 Thailand Science Park, Pahonyothin Road, Khong Luang 12120, Thailand
- School of Food Science and Technology, Faculty of Science and Technology, Thammasat University, 99 Mhu 18, Pahonyothin Road, Khong Luang 12120, Thailand
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Wang J, Zhang M, Yang J, Yang X, Zhang J, Zhao Z. Type A Trichothecene Metabolic Profile Differentiation, Mechanisms, Biosynthetic Pathways, and Evolution in Fusarium Species-A Mini Review. Toxins (Basel) 2023; 15:446. [PMID: 37505715 PMCID: PMC10467051 DOI: 10.3390/toxins15070446] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 07/01/2023] [Accepted: 07/03/2023] [Indexed: 07/29/2023] Open
Abstract
Trichothecenes are the most common Fusarium toxins detected in grains and related products. Type A trichothecenes are among the mycotoxins of greatest concern to food and feed safety due to their high toxicity. Recently, two different trichothecene genotypes within Fusarium species were reported. The available information showed that Tri1 and Tri16 genes are the key determinants of the trichothecene profiles of T-2 and DAS genotypes. In this review, polymorphisms in the Tri1 and Tri16 genes in the two genotypes were investigated. Meanwhile, the functions of genes involved in DAS and NEO biosynthesis are discussed. The possible biosynthetic pathways of DAS and NEO are proposed in this review, which will facilitate the understanding of the synthesis process of trichothecenes in Fusarium strains and may also inspire researchers to design and conduct further research. Together, the review provides insight into trichothecene profile differentiation and Tri gene evolutionary processes responsible for the structural diversification of trichothecene produced by Fusarium.
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Affiliation(s)
- Jianhua Wang
- Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (M.Z.); (J.Y.); (X.Y.); (J.Z.); (Z.Z.)
| | - Mengyuan Zhang
- Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (M.Z.); (J.Y.); (X.Y.); (J.Z.); (Z.Z.)
- College of Food Sciences & Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Junhua Yang
- Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (M.Z.); (J.Y.); (X.Y.); (J.Z.); (Z.Z.)
| | - Xianli Yang
- Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (M.Z.); (J.Y.); (X.Y.); (J.Z.); (Z.Z.)
| | - Jiahui Zhang
- Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (M.Z.); (J.Y.); (X.Y.); (J.Z.); (Z.Z.)
| | - Zhihui Zhao
- Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (M.Z.); (J.Y.); (X.Y.); (J.Z.); (Z.Z.)
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Tannous J, Cosetta CM, Drott MT, Rush TA, Abraham PE, Giannone RJ, Keller NP, Wolfe BE. LaeA-Regulated Fungal Traits Mediate Bacterial Community Assembly. mBio 2023:e0076923. [PMID: 37162223 DOI: 10.1128/mbio.00769-23] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023] Open
Abstract
Potent antimicrobial metabolites are produced by filamentous fungi in pure culture, but their ecological functions in nature are often unknown. Using an antibacterial Penicillium isolate and a cheese rind microbial community, we demonstrate that a fungal specialized metabolite can regulate the diversity of bacterial communities. Inactivation of the global regulator, LaeA, resulted in the loss of antibacterial activity in the Penicillium isolate. Cheese rind bacterial communities assembled with the laeA deletion strain had significantly higher bacterial abundances than the wild-type strain. RNA-sequencing and metabolite profiling demonstrated a striking reduction in the expression and production of the natural product pseurotin in the laeA deletion strain. Inactivation of a core gene in the pseurotin biosynthetic cluster restored bacterial community composition, confirming the role of pseurotins in mediating bacterial community assembly. Our discovery demonstrates how global regulators of fungal transcription can control the assembly of bacterial communities and highlights an ecological role for a widespread class of fungal specialized metabolites. IMPORTANCE Cheese rinds are economically important microbial communities where fungi can impact food quality and aesthetics. The specific mechanisms by which fungi can regulate bacterial community assembly in cheeses, other fermented foods, and microbiomes in general are largely unknown. Our study highlights how specialized metabolites secreted by a Penicillium species can mediate cheese rind development via differential inhibition of bacterial community members. Because LaeA regulates specialized metabolites and other ecologically relevant traits in a wide range of filamentous fungi, this global regulator may have similar impacts in other fungus-dominated microbiomes.
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Affiliation(s)
- Joanna Tannous
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Casey M Cosetta
- Department of Biology, Tufts University, Medford, Massachusetts, USA
| | - Milton T Drott
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- USDA-ARS Cereal Disease Laboratory, St. Paul, Minnesota, USA
| | - Tomás A Rush
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Paul E Abraham
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Richard J Giannone
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA
| | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Benjamin E Wolfe
- Department of Biology, Tufts University, Medford, Massachusetts, USA
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Wei X, Wang WG, Matsuda Y. Branching and converging pathways in fungal natural product biosynthesis. Fungal Biol Biotechnol 2022; 9:6. [PMID: 35255990 PMCID: PMC8902786 DOI: 10.1186/s40694-022-00135-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Accepted: 02/19/2022] [Indexed: 12/15/2022] Open
Abstract
AbstractIn nature, organic molecules with great structural diversity and complexity are synthesized by utilizing a relatively small number of starting materials. A synthetic strategy adopted by nature is pathway branching, in which a common biosynthetic intermediate is transformed into different end products. A natural product can also be synthesized by the fusion of two or more precursors generated from separate metabolic pathways. This review article summarizes several representative branching and converging pathways in fungal natural product biosynthesis to illuminate how fungi are capable of synthesizing a diverse array of natural products.
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7
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Chen L, Yang J, Wang H, Yang X, Zhang C, Zhao Z, Wang J. NX toxins: New threat posed by Fusarium graminearum species complex. Trends Food Sci Technol 2022. [DOI: 10.1016/j.tifs.2021.11.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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8
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Lu Y, Qiu J, Wang S, Xu J, Ma G, Shi J, Bao Z. Species Diversity and Toxigenic Potential of Fusarium incarnatum-equiseti Species Complex Isolates from Rice and Soybean in China. PLANT DISEASE 2021; 105:2628-2636. [PMID: 33393357 DOI: 10.1094/pdis-09-20-1907-re] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Fusarium incarnatum-equiseti species complex (FIESC) strains are generally considered moderately virulent to many agricultural crops and produce a variety of mycotoxins, which represent a serious threat to food safety and public health. The occurrence of the FIESC strain in agricultural crops has been reported in various climatic regions, but detailed information on the species composition and toxigenic ability is rare in China. In this study, phylogenetic analyses were performed with combined sequences of EF-1a and RPB2 of 186 Fusarium isolates obtained from rice (Oryza sativa) and soybean (Glycine max). Twelve species were identified and 156 of the isolates were resolved within the Incarnatum clade of the FIESC species. Host influenced the population composition: rice isolates belonged to 12 species, among which FIESC 16, 18, and 24 strains were predominant; whereas five species were found among soybean isolates and FIESC 1, 16, and 18 strains dominated. Forty-three isolates were arbitrarily selected and analyzed for their Tri gene sequences and mycotoxigenic potential. Phylogenetic results based on the combined Tri5, Tri7, and Tri13 sequences were coincident with those from housekeeping markers. Type-A and -B trichothecenes were the main metabolites. Diacetoxyscirpenol was detected in all strains at varying concentrations. Nivalenol, 4-acetyl nivalenol, 3-acetyl deoxynivalenol, and neosolaniol were produced in members of the FIESC 1, 3, 7, 8, 15, 16, 17, and 18 strains. Our findings contribute valuable phylogenetic and toxigenic information necessary for the risk evaluation of mycotoxins in agricultural products.
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Affiliation(s)
- Yunan Lu
- College of Marine Life and Fisheries, Jiangsu Ocean University, Lianyungang 222005, China
| | - Jianbo Qiu
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base, Ministry of Science and Technology/Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Shufang Wang
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base, Ministry of Science and Technology/Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
| | - Jianhong Xu
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base, Ministry of Science and Technology/Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Guizhen Ma
- College of Marine Life and Fisheries, Jiangsu Ocean University, Lianyungang 222005, China
| | - Jianrong Shi
- Jiangsu Key Laboratory for Food Quality and Safety-State Key Laboratory Cultivation Base, Ministry of Science and Technology/Institute of Food Safety and Nutrition, Jiangsu Academy of Agricultural Sciences, Nanjing 210014, China
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Zenghai Bao
- College of Marine Life and Fisheries, Jiangsu Ocean University, Lianyungang 222005, China
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9
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A review of mycotoxin biosynthetic pathways: associated genes and their expressions under the influence of climatic factors. FUNGAL BIOL REV 2021. [DOI: 10.1016/j.fbr.2021.04.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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10
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Munkvold GP, Proctor RH, Moretti A. Mycotoxin Production in Fusarium According to Contemporary Species Concepts. ANNUAL REVIEW OF PHYTOPATHOLOGY 2021; 59:373-402. [PMID: 34077240 DOI: 10.1146/annurev-phyto-020620-102825] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Fusarium is one of the most important genera of plant-pathogenic fungi in the world and arguably the world's most important mycotoxin-producing genus. Fusarium species produce a staggering array of toxic metabolites that contribute to plant disease and mycotoxicoses in humans and other animals. A thorough understanding of the mycotoxin potential of individual species is crucial for assessing the toxicological risks associated with Fusarium diseases. There are thousands of reports of mycotoxin production by various species, and there have been numerous attempts to summarize them. These efforts have been complicated by competing classification systems based on morphology, sexual compatibility, and phylogenetic relationships. The current depth of knowledge of Fusarium genomes and mycotoxin biosynthetic pathways provides insights into how mycotoxin production is distributedamong species and multispecies lineages (species complexes) in the genus as well as opportunities to clarify and predict mycotoxin risks connected with known and newly described species. Here, we summarize mycotoxin production in the genus Fusarium and how mycotoxin risk aligns with current phylogenetic species concepts.
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Affiliation(s)
- Gary P Munkvold
- Department of Plant Pathology and Microbiology and Seed Science Center, Iowa State University, Ames, Iowa 50010, USA;
| | - Robert H Proctor
- Mycotoxin Prevention and Applied Microbiology Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, USDA, Peoria, Illinois 61604, USA;
| | - Antonio Moretti
- Institute of Sciences of Food Production, National Research Council of Italy (CNR-ISPA), 70126 Bari, Italy;
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11
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Witte TE, Harris LJ, Nguyen HDT, Hermans A, Johnston A, Sproule A, Dettman JR, Boddy CN, Overy DP. Apicidin biosynthesis is linked to accessory chromosomes in Fusarium poae isolates. BMC Genomics 2021; 22:591. [PMID: 34348672 PMCID: PMC8340494 DOI: 10.1186/s12864-021-07617-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 03/08/2021] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Fusarium head blight is a disease of global concern that reduces crop yields and renders grains unfit for consumption due to mycotoxin contamination. Fusarium poae is frequently associated with cereal crops showing symptoms of Fusarium head blight. While previous studies have shown F. poae isolates produce a range of known mycotoxins, including type A and B trichothecenes, fusarins and beauvericin, genomic analysis suggests that this species may have lineage-specific accessory chromosomes with secondary metabolite biosynthetic gene clusters awaiting description. METHODS We examined the biosynthetic potential of 38 F. poae isolates from Eastern Canada using a combination of long-read and short-read genome sequencing and untargeted, high resolution mass spectrometry metabolome analysis of extracts from isolates cultured in multiple media conditions. RESULTS A high-quality assembly of isolate DAOMC 252244 (Fp157) contained four core chromosomes as well as seven additional contigs with traits associated with accessory chromosomes. One of the predicted accessory contigs harbours a functional biosynthetic gene cluster containing homologs of all genes associated with the production of apicidins. Metabolomic and genomic analyses confirm apicidins are produced in 4 of the 38 isolates investigated and genomic PCR screening detected the apicidin synthetase gene APS1 in approximately 7% of Eastern Canadian isolates surveyed. CONCLUSIONS Apicidin biosynthesis is linked to isolate-specific putative accessory chromosomes in F. poae. The data produced here are an important resource for furthering our understanding of accessory chromosome evolution and the biosynthetic potential of F. poae.
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Affiliation(s)
- Thomas E. Witte
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, Canada
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Canada
| | - Linda J. Harris
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, Canada
| | - Hai D. T. Nguyen
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, Canada
| | - Anne Hermans
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, Canada
| | - Anne Johnston
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, Canada
| | - Amanda Sproule
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, Canada
| | - Jeremy R. Dettman
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, Canada
| | - Christopher N. Boddy
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Canada
| | - David P. Overy
- Agriculture and Agri-Food Canada, Ottawa Research and Development Centre, Ottawa, Canada
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12
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Proctor RH, McCormick SP, Gutiérrez S. Genetic bases for variation in structure and biological activity of trichothecene toxins produced by diverse fungi. Appl Microbiol Biotechnol 2020; 104:5185-5199. [PMID: 32328680 DOI: 10.1007/s00253-020-10612-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/01/2020] [Accepted: 04/05/2020] [Indexed: 11/26/2022]
Abstract
Trichothecenes are sesquiterpene toxins produced by diverse but relatively few fungal species in at least three classes of Ascomycetes: Dothideomycetes, Eurotiomycetes, and Sordariomycetes. Approximately 200 structurally distinct trichothecene analogs have been described, but a given fungal species typically produces only a small subset of analogs. All trichothecenes share a core structure consisting of a four-ring nucleus known as 12,13-epoxytrichothec-9-ene. This structure can be substituted at various positions with hydroxyl, acyl, or keto groups to give rise to the diversity of trichothecene structures that has been described. Over the last 30 years, the genetic and biochemical pathways required for trichothecene biosynthesis in several species of the fungi Fusarium and Trichoderma have been elucidated. In addition, phylogenetic and functional analyses of trichothecene biosynthetic (TRI) genes from fungi in multiple genera have provided insights into how acquisition, loss, and changes in functions of TRI genes have given rise to the diversity of trichothecene structures. These analyses also suggest both divergence and convergence of TRI gene function during the evolutionary history of trichothecene biosynthesis. What has driven trichothecene structural diversification remains an unanswered question. However, insight into the role of trichothecenes in plant pathogenesis of Fusarium species and into plant glucosyltransferases that detoxify the toxins by glycosylating them point to a possible driver. Because the glucosyltransferases can have substrate specificity, changes in trichothecene structures produced by a fungus could allow it to evade detoxification by the plant enzymes. Thus, it is possible that advantages conferred by evading detoxification have contributed to trichothecene structural diversification. KEY POINTS : • TRI genes have evolved by diverse processes: loss, acquisition and changes in function. • Some TRI genes have acquired the same function by convergent evolution. • Some other TRI genes have evolved divergently to have different functions. • Some TRI genes were acquired or resulted from diversification in function of other genes. • Substrate specificity of plant glucosyltransferases could drive trichothecene diversity.
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Affiliation(s)
- R H Proctor
- United States Department of Agriculture, Mycotoxin Prevention and Applied Microbiology Research Unit, National Center for Agricultural Utilization Research, Peoria, IL, 61604-3902, USA.
| | - S P McCormick
- United States Department of Agriculture, Mycotoxin Prevention and Applied Microbiology Research Unit, National Center for Agricultural Utilization Research, Peoria, IL, 61604-3902, USA
| | - S Gutiérrez
- Area of Microbiology, University of León, Campus de Ponferrada, 24400, Ponferrada, Spain.
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13
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Gain and loss of a transcription factor that regulates late trichothecene biosynthetic pathway genes in Fusarium. Fungal Genet Biol 2019; 136:103317. [PMID: 31841670 DOI: 10.1016/j.fgb.2019.103317] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 12/03/2019] [Accepted: 12/04/2019] [Indexed: 02/06/2023]
Abstract
Trichothecenes are among the mycotoxins of most concern to food and feed safety and are produced by species in two lineages of Fusarium: the F. incarnatum-equiseti (FIESC) and F. sambucinum (FSAMSC) species complexes. Previous functional analyses of the trichothecene biosynthetic gene (TRI) cluster in members of FSAMSC indicate that the transcription factor gene TRI6 activates expression of other TRI cluster genes. In addition, previous sequence analyses indicate that the FIESC TRI cluster includes TRI6 and another uncharacterized transcription factor gene (hereafter TRI21) that was not reported in FSAMSC. Here, gene deletion analysisindicated that in FIESC TRI6 functions in a manner similar to FSAMSC, whereas TRI21 activated expression of some genes that function late in the trichothecene biosynthetic pathway but not early-pathway genes. Consistent with this finding, TRI21 was required for formation of diacetoxyscripenol, a late-trichothecene-pathway product, but not for isotrichodermin, an early-pathway product. Although intact homologs of TRI21 were not detected in FSAMSC or other trichothecene-producing fungal genera, TRI21 fragments were detected in some FSAMSC species. This suggests that the gene was acquired by Fusarium after divergence from other trichothecene-producing fungi, was subsequently lost in FSAMSC, but was retained in FIESC. Together, our results indicate fundamental differences in regulation of trichothecene biosynthesis in FIESC and FSAMSC.
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Villani A, Proctor RH, Kim HS, Brown DW, Logrieco AF, Amatulli MT, Moretti A, Susca A. Variation in secondary metabolite production potential in the Fusarium incarnatum-equiseti species complex revealed by comparative analysis of 13 genomes. BMC Genomics 2019; 20:314. [PMID: 31014248 PMCID: PMC6480918 DOI: 10.1186/s12864-019-5567-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 02/25/2019] [Indexed: 11/29/2022] Open
Abstract
Background The Fusarium incarnatum-equiseti species complex (FIESC) comprises 33 phylogenetically distinct species that have been recovered from diverse biological sources, but have been most often isolated from agricultural plants and soils. Collectively, members of FIESC can produce diverse mycotoxins. However, because the species diversity of FIESC has been recognized only recently, the potential of species to cause mycotoxin contamination of crop plants is unclear. In this study, therefore, we used comparative genomics to investigate the distribution of and variation in genes and gene clusters responsible for the synthesis of mycotoxins and other secondary metabolites (SMs) in FIESC. Results We examined genomes of 13 members of FIESC that were selected based primarily on their phylogenetic diversity and/or occurrence on crops. The presence and absence of SM biosynthetic gene clusters varied markedly among the genomes. For example, the trichothecene mycotoxin as well as the carotenoid and fusarubin pigment clusters were present in all genomes examined, whereas the enniatin, fusarin, and zearalenone mycotoxin clusters were present in only some genomes. Some clusters exhibited discontinuous patterns of distribution in that their presence and absence was not correlated with the phylogenetic relationships of species. We also found evidence that cluster loss and horizontal gene transfer have contributed to such distribution patterns. For example, a combination of multiple phylogenetic analyses suggest that five NRPS and seven PKS genes were introduced into FIESC from other Fusarium lineages. Conclusion Our results suggest that although the portion of the genome devoted to SM biosynthesis has remained similar during the evolutionary diversification of FIESC, the ability to produce SMs could be affected by the different distribution of related functional and complete gene clusters. Electronic supplementary material The online version of this article (10.1186/s12864-019-5567-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alessandra Villani
- Institute of Sciences of Food Production, National Research Council, Bari, Italy
| | - Robert H Proctor
- Department of Agriculture Peoria, National Center for Agricultural Utilization Research, U.S., Peoria, IL, USA
| | - Hye-Seon Kim
- Department of Agriculture Peoria, National Center for Agricultural Utilization Research, U.S., Peoria, IL, USA
| | - Daren W Brown
- Department of Agriculture Peoria, National Center for Agricultural Utilization Research, U.S., Peoria, IL, USA
| | - Antonio F Logrieco
- Institute of Sciences of Food Production, National Research Council, Bari, Italy
| | - Maria Teresa Amatulli
- Institute of Sciences of Food Production, National Research Council, Bari, Italy.,Thales Alenia Space Italia, Torino, Italy
| | - Antonio Moretti
- Institute of Sciences of Food Production, National Research Council, Bari, Italy.
| | - Antonia Susca
- Institute of Sciences of Food Production, National Research Council, Bari, Italy
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Yoshinari T, Takeda N, Watanabe M, Sugita-Konishi Y. Development of an Analytical Method for Simultaneous Determination of the Modified Forms of 4,15-Diacetoxyscirpenol and their Occurrence in Japanese Retail Food. Toxins (Basel) 2018; 10:E178. [PMID: 29701674 PMCID: PMC5983234 DOI: 10.3390/toxins10050178] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 04/18/2018] [Accepted: 04/24/2018] [Indexed: 11/23/2022] Open
Abstract
4,15-Diacetoxyscirpenol (4,15-DAS) is a type A trichothecene mycotoxin produced by Fusarium species. Four modified forms of 4,15-DAS including 7-hydroxydiacetoxyscirpenol, 7,8-dihydroxydiacetoxyscirpenol, 4β,8α,15-triacetoxy-3α,7α-dihydroxy-12,13-epoxytrichothec-9-ene and 4,15-diacetylnivalenol were purified from cultures of F. equiseti. An analytical method using a multifunctional column has been developed for the simultaneous determination of 4,15-DAS, its four modified forms, T-2 toxin, HT-2 toxin and neosolaniol in cereals. The performance of the current method was evaluated, and a total of 248 samples of five different commodities were analyzed for over two years by this method. 4,15-DAS was detected in Job’s tears products, corn flour and azuki bean, but it was not found in wheat flour or rye flour. The four modified forms of 4,15-DAS were detected in samples of Job’s tears products, contaminated by 4,15-DAS. This is the first report on quantification of the modified forms of 4,15-DAS in cereals.
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Affiliation(s)
- Tomoya Yoshinari
- Division of Microbiology, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa 210-9501, Japan.
| | - Nanami Takeda
- Department of Food and Life Sciences, Azabu University, 1-17-71 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5201, Japan.
| | - Maiko Watanabe
- Division of Microbiology, National Institute of Health Sciences, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki-shi, Kanagawa 210-9501, Japan.
| | - Yoshiko Sugita-Konishi
- Department of Food and Life Sciences, Azabu University, 1-17-71 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5201, Japan.
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González-Jartín JM, Alfonso A, Sainz MJ, Vieytes MR, Botana LM. Detection of new emerging type-A trichothecenes by untargeted mass spectrometry. Talanta 2018; 178:37-42. [DOI: 10.1016/j.talanta.2017.09.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 09/01/2017] [Accepted: 09/04/2017] [Indexed: 10/18/2022]
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17
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Zheng X, Zhang X, Zhao L, Apaliya MT, Yang Q, Sun W, Zhang X, Zhang H. Screening of Deoxynivalenol Producing Strains and Elucidation of Possible Toxigenic Molecular Mechanism. Toxins (Basel) 2017; 9:toxins9060184. [PMID: 28587179 PMCID: PMC5488034 DOI: 10.3390/toxins9060184] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 05/24/2017] [Accepted: 05/27/2017] [Indexed: 12/13/2022] Open
Abstract
In this study, seven strains of Fusarium graminearum were isolated from wheat, of which six were identified to produce deoxynivalenol and the production of deoxynivalenol was assessed. F. graminearum strain Fg1 was noted to produce 1.0 μg/g deoxynivalenol during the incubation period in the Czapek yeast broth, while none was detected in F. graminearum strain Fg2. Hence, the differences in proteomes and transcriptomes of Fg1 and Fg2 were compared to analyze the mechanism underlying deoxynivalenol production. Among the 66 significantly differentially expressed proteins in Fg1, 39 and 27 were more or less abundant expressed. Functional analysis suggested that the enzymes involved in the methylerythritol 4-phosphate and mevalonate pathways, which provide a substrate for biosynthesis of farnesyl pyrophosphate, a precursor of DON, were activated in Fg1. The transcriptomics data demonstrated that the expression level of a majority of genes, including trichothecene biosynthetic genes, protein kinases, and transcription factors, involved in trichothecene biosynthesis was higher in Fg1 than in Fg2. The results also revealed differential expression profiles of deoxynivalenol biosynthesis genes in strains Fg1 and Fg2, which emphasized their deoxynivalenol producing ability and the underlying mechanism.
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Affiliation(s)
- Xiangfeng Zheng
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China.
| | - Xiaoli Zhang
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China.
| | - Lina Zhao
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China.
| | - Maurice T Apaliya
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China.
| | - Qiya Yang
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China.
| | - Wei Sun
- Zhen Jiang Grain and Oil Quality Testing Center, Zhenjiang 212013, Jiangsu, China.
| | - Xiaoyun Zhang
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China.
| | - Hongyin Zhang
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, Jiangsu, China.
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Maeda K, Tanaka A, Sugiura R, Koshino H, Tokai T, Sato M, Nakajima Y, Tanahashi Y, Kanamaru K, Kobayashi T, Nishiuchi T, Fujimura M, Takahashi-Ando N, Kimura M. Hydroxylations of trichothecene rings in the biosynthesis ofFusariumtrichothecenes: evolution of alternative pathways in the nivalenol chemotype. Environ Microbiol 2016; 18:3798-3811. [DOI: 10.1111/1462-2920.13338] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 04/08/2016] [Accepted: 04/08/2016] [Indexed: 11/29/2022]
Affiliation(s)
- Kazuyuki Maeda
- Graduate School of Bioagricultural Sciences; Nagoya University, Furo-cho, Chikusa; Nagoya Aichi 464-8601 Japan
| | - Akira Tanaka
- Graduate School of Science and Engineering; Toyo University; Kujirai 2100 Kawagoe Saitama 350-0815 Japan
| | - Ryosuke Sugiura
- Graduate School of Bioagricultural Sciences; Nagoya University, Furo-cho, Chikusa; Nagoya Aichi 464-8601 Japan
| | - Hiroyuki Koshino
- Molecular Structure Characterization Unit, RIKEN CSRS; 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Takeshi Tokai
- Graduate School of Life Sciences; Toyo University; 1-1-1 Izumino, Itakura Gunma 374-0193 Japan
- Plant and Microbial Metabolic Engineering Research Unit; RIKEN DRI; 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Masayuki Sato
- Graduate School of Life Sciences; Toyo University; 1-1-1 Izumino, Itakura Gunma 374-0193 Japan
- Plant and Microbial Metabolic Engineering Research Unit; RIKEN DRI; 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Yuichi Nakajima
- Graduate School of Bioagricultural Sciences; Nagoya University, Furo-cho, Chikusa; Nagoya Aichi 464-8601 Japan
| | - Yoshikazu Tanahashi
- Graduate School of Bioagricultural Sciences; Nagoya University, Furo-cho, Chikusa; Nagoya Aichi 464-8601 Japan
| | - Kyoko Kanamaru
- Graduate School of Bioagricultural Sciences; Nagoya University, Furo-cho, Chikusa; Nagoya Aichi 464-8601 Japan
| | - Tetsuo Kobayashi
- Graduate School of Bioagricultural Sciences; Nagoya University, Furo-cho, Chikusa; Nagoya Aichi 464-8601 Japan
| | - Takumi Nishiuchi
- Division of Functional Genomics; Advanced Science Research Centre; 13-1 Takara-machi, Kanazawa University Kanazawa Ishikawa 920-0934 Japan
| | - Makoto Fujimura
- Graduate School of Life Sciences; Toyo University; 1-1-1 Izumino, Itakura Gunma 374-0193 Japan
| | - Naoko Takahashi-Ando
- Graduate School of Science and Engineering; Toyo University; Kujirai 2100 Kawagoe Saitama 350-0815 Japan
- Plant and Microbial Metabolic Engineering Research Unit; RIKEN DRI; 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Makoto Kimura
- Graduate School of Bioagricultural Sciences; Nagoya University, Furo-cho, Chikusa; Nagoya Aichi 464-8601 Japan
- Plant and Microbial Metabolic Engineering Research Unit; RIKEN DRI; 2-1 Hirosawa Wako Saitama 351-0198 Japan
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Variation in type A trichothecene production and trichothecene biosynthetic genes in Fusarium goolgardi from natural ecosystems of Australia. Toxins (Basel) 2015; 7:4577-94. [PMID: 26556373 PMCID: PMC4663521 DOI: 10.3390/toxins7114577] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 10/20/2015] [Accepted: 10/26/2015] [Indexed: 01/21/2023] Open
Abstract
Fusarium goolgardi, isolated from the grass tree Xanthorrhoea glauca in natural ecosystems of Australia, is closely related to fusaria that produce a subgroup of trichothecene (type A) mycotoxins that lack a carbonyl group at carbon atom 8 (C-8). Mass spectrometric analysis revealed that F. goolgardi isolates produce type A trichothecenes, but exhibited one of two chemotypes. Some isolates (50%) produced multiple type A trichothecenes, including 4,15-diacetoxyscirpenol (DAS), neosolaniol (NEO), 8-acetylneosolaniol (Ac-NEO) and T-2 toxin (DAS-NEO-T2 chemotype). Other isolates (50%) produced only DAS (DAS chemotype). In the phylogenies inferred from DNA sequences of genes encoding the RNA polymerase II largest (RPB1) and second largest (RPB2) subunits as well as the trichothecene biosynthetic genes (TRI), F. goolgardi isolates were resolved as a monophyletic clade, distinct from other type A trichothecene-producing species. However, the relationships of F. goolgardi to the other species varied depending on whether phylogenies were inferred from RPB1 and RPB2, the 12-gene TRI cluster, the two-gene TRI1-TRI16 locus, or the single-gene TRI101 locus. Phylogenies based on different TRI loci resolved isolates with different chemotypes into distinct clades, even though only the TRI1-TRI16 locus is responsible for structural variation at C-8. Sequence analysis indicated that TRI1 and TRI16 are functional in F. goolgardi isolates with the DAS-NEO-T2 chemotype, but non-functional in isolates with DAS chemotype due to the presence of premature stop codons caused by a point mutation.
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Subramaniam R, Narayanan S, Walkowiak S, Wang L, Joshi M, Rocheleau H, Ouellet T, Harris LJ. Leucine metabolism regulates TRI6 expression and affects deoxynivalenol production and virulence in Fusarium graminearum. Mol Microbiol 2015; 98:760-9. [PMID: 26248604 DOI: 10.1111/mmi.13155] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2015] [Indexed: 02/04/2023]
Abstract
TRI6 is a positive regulator of the trichothecene gene cluster and the production of trichothecene mycotoxins [deoxynivalenol (DON)] and acetylated forms such as 15-Acetyl-DON) in the cereal pathogen Fusarium graminearum. As a global transcriptional regulator, TRI6 expression is modulated by nitrogen-limiting conditions, sources of nitrogen and carbon, pH and light. However, the mechanism by which these diverse environmental factors affect TRI6 expression remains underexplored. In our effort to understand how nutrients affect TRI6 regulation, comparative digital expression profiling was performed with a wild-type F. graminearum and a Δtri6 mutant strain, grown in nutrient-rich conditions. Analysis showed that TRI6 negatively regulates genes of the branched-chain amino acid (BCAA) metabolic pathway. Feeding studies with deletion mutants of MCC, encoding methylcrotonyl-CoA-carboxylase, one of the key enzymes of leucine metabolism, showed that addition of leucine specifically down-regulated TRI6 expression and reduced 15-ADON accumulation. Constitutive expression of TRI6 in the Δmcc mutant strain restored 15-ADON production. A combination of cellophane breach assays and pathogenicity experiments on wheat demonstrated that disrupting the leucine metabolic pathway significantly reduced disease. These findings suggest a complex interaction between one of the primary metabolic pathways with a global regulator of mycotoxin biosynthesis and virulence in F. graminearum.
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Affiliation(s)
- Rajagopal Subramaniam
- Agriculture and Agri-Food Canada, Eastern Cereal Research Centre, Ottawa, K1A0C6, Canada
| | - Swara Narayanan
- Agriculture and Agri-Food Canada, Eastern Cereal Research Centre, Ottawa, K1A0C6, Canada
| | - Sean Walkowiak
- Agriculture and Agri-Food Canada, Eastern Cereal Research Centre, Ottawa, K1A0C6, Canada.,Department of Biology, Carleton University, 1125 Colonel By, Ottawa, K1S5B6, Canada
| | - Li Wang
- Agriculture and Agri-Food Canada, Eastern Cereal Research Centre, Ottawa, K1A0C6, Canada
| | - Manisha Joshi
- Agriculture and Agri-Food Canada, Eastern Cereal Research Centre, Ottawa, K1A0C6, Canada
| | - Hélène Rocheleau
- Agriculture and Agri-Food Canada, Eastern Cereal Research Centre, Ottawa, K1A0C6, Canada
| | - Thérèse Ouellet
- Agriculture and Agri-Food Canada, Eastern Cereal Research Centre, Ottawa, K1A0C6, Canada
| | - Linda J Harris
- Agriculture and Agri-Food Canada, Eastern Cereal Research Centre, Ottawa, K1A0C6, Canada
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21
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Buśko M, Kulik T, Ostrowska A, Góral T, Perkowski J. Quantitative volatile compound profiles in fungal cultures of three differentFusarium graminearumchemotypes. FEMS Microbiol Lett 2014; 359:85-93. [DOI: 10.1111/1574-6968.12569] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 06/27/2014] [Accepted: 08/05/2014] [Indexed: 11/29/2022] Open
Affiliation(s)
- Maciej Buśko
- Poznań University of Life Sciences; Department of Chemistry; Poznań Poland
| | - Tomasz Kulik
- Department of Diagnostics and Plant Pathophysiology; University of Warmia and Mazury; Olsztyn Poland
- Department of Botany and Nature Protection; University of Warmia and Mazury; Olsztyn Poland
| | - Anna Ostrowska
- Poznań University of Life Sciences; Department of Chemistry; Poznań Poland
| | - Tomasz Góral
- Department of Plant Pathology; Plant Breeding and Acclimatization Institute NRI; Blonie Poland
| | - Juliusz Perkowski
- Poznań University of Life Sciences; Department of Chemistry; Poznań Poland
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22
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Kimura M, Tokai T, Takahashi-Ando N, Ohsato S, Fujimura M. Molecular and Genetic Studies ofFusariumTrichothecene Biosynthesis: Pathways, Genes, and Evolution. Biosci Biotechnol Biochem 2014; 71:2105-23. [PMID: 17827683 DOI: 10.1271/bbb.70183] [Citation(s) in RCA: 267] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Trichothecenes are a large family of sesquiterpenoid secondary metabolites of Fusarium species (e.g., F. graminearum) and other molds. They are major mycotoxins that can cause serious problems when consumed via contaminated cereal grains. In the past 20 years, an outline of the trichothecene biosynthetic pathway has been established based on the results of precursor feeding experiments and blocked mutant analyses. Following the isolation of the pathway gene Tri5 encoding the first committed enzyme trichodiene synthase, 10 biosynthesis genes (Tri genes; two regulatory genes, seven pathway genes, and one transporter gene) were functionally identified in the Tri5 gene cluster. At least three pathway genes, Tri101 (separated alone), and Tri1 and Tri16 (located in the Tri1-Tri16 two-gene cluster), were found outside of the Tri5 gene cluster. In this review, we summarize the current understanding of the pathways of biosynthesis, the functions of cloned Tri genes, and the evolution of Tri genes, focusing on Fusarium species.
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Affiliation(s)
- Makoto Kimura
- Plant & Microbial Metabolic Engineering Research Unit, Discovery Research Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
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23
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Reverberi M, Fabbri AA, Fanelli C. Ochratoxin A and Related Mycotoxins. Fungal Biol 2014. [DOI: 10.1007/978-1-4939-1191-2_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Moretti A, Susca A, Mulé G, Logrieco AF, Proctor RH. Molecular biodiversity of mycotoxigenic fungi that threaten food safety. Int J Food Microbiol 2013; 167:57-66. [PMID: 23859402 DOI: 10.1016/j.ijfoodmicro.2013.06.033] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 06/25/2013] [Accepted: 06/28/2013] [Indexed: 01/20/2023]
Abstract
Fungal biodiversity is one of the most important contributors to the occurrence and severity of mycotoxin contamination of crop plants. Phenotypic and metabolic plasticity has enabled mycotoxigenic fungi to colonize a broad range of agriculturally important crops and to adapt to a range of environmental conditions. New mycotoxin-commodity combinations provide evidence for the ability of fungi to adapt to changing conditions and the emergence of genotypes that confer enhanced aggressiveness toward plants and/or altered mycotoxin production profiles. Perhaps the most important contributor to qualitative differences in mycotoxin production among fungi is variation in mycotoxin biosynthetic genes. Molecular genetic and biochemical analyses of toxigenic fungi have elucidated specific differences in biosynthetic genes that are responsible for intra- and inter-specific differences in mycotoxin production. For Aspergillus and Fusarium, the mycotoxigenic genera of greatest concern, variation in biosynthetic genes responsible for production of individual families of mycotoxins appears to be the result of evolutionary adaptation. Examples of such variation have been reported for: a) aflatoxin biosynthetic genes in Aspergillus flavus and Aspergillus parasiticus; b) trichothecene biosynthetic genes within and among Fusarium species; and c) fumonisin biosynthetic genes in Aspergillus and Fusarium species. Understanding the variation in these biosynthetic genes and the basis for variation in mycotoxin production is important for accurate assessment of the risks that fungi pose to food safety and for prevention of mycotoxin contamination of crops in the field and in storage.
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Affiliation(s)
- A Moretti
- Institute of Sciences of Food Production, CNR, Bari, Italy.
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25
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McCormick SP, Stanley AM, Stover NA, Alexander NJ. Trichothecenes: from simple to complex mycotoxins. Toxins (Basel) 2011; 3:802-14. [PMID: 22069741 PMCID: PMC3202860 DOI: 10.3390/toxins3070802] [Citation(s) in RCA: 292] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Revised: 06/10/2011] [Accepted: 06/29/2011] [Indexed: 01/07/2023] Open
Abstract
As the world's population grows, access to a safe food supply will continue to be a global priority. In recent years, the world has experienced an increase in mycotoxin contamination of grains due to climatic and agronomic changes that encourage fungal growth during cultivation. A number of the molds that are plant pathogens produce trichothecene mycotoxins, which are known to cause serious human and animal toxicoses. This review covers the types of trichothecenes, their complexity, and proposed biosynthetic pathways of trichothecenes.
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Affiliation(s)
- Susan P. McCormick
- Bacterial Foodborne Pathogens and Mycology, National Center for Agricultural Utilization Research, U.S. Department of Agriculture-Agriculture Research Service, Peoria, IL 61604, USA;
- Author to whom correspondence should be addressed; ; Tel.:+1-309-681-6381; Fax:+1-309-681-6627
| | - April M. Stanley
- Biology Department, Bradley University, Peoria, IL 61625, USA; (A.M.S.); (N.A.S.)
| | - Nicholas A. Stover
- Biology Department, Bradley University, Peoria, IL 61625, USA; (A.M.S.); (N.A.S.)
| | - Nancy J. Alexander
- Bacterial Foodborne Pathogens and Mycology, National Center for Agricultural Utilization Research, U.S. Department of Agriculture-Agriculture Research Service, Peoria, IL 61604, USA;
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Regulation of trichothecene biosynthesis in Fusarium: recent advances and new insights. Appl Microbiol Biotechnol 2011; 91:519-28. [PMID: 21691790 DOI: 10.1007/s00253-011-3397-x] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Revised: 05/23/2011] [Accepted: 05/23/2011] [Indexed: 01/14/2023]
Abstract
Trichothecenes are toxic secondary metabolites produced by filamentous fungi mainly belonging to the Fusarium genus. Production of these mycotoxins occurs during infection of crops and is a threat to human and animal health. Although the pathway for biosynthesis of trichothecenes is well established, the regulation of the Tri genes implicated in the pathway remains poorly understood. Most of the Tri genes are gathered in a cluster which contains two transcriptional regulators controlling the expression of the other Tri genes. The regulation of secondary metabolites biosynthesis in most fungal genera has been recently shown to be controlled by various regulatory systems in response to external environment. The control of the "Tri cluster" by non-cluster regulators in Fusarium was not clearly demonstrated until recently. This review covers the recent advances concerning the regulation of trichothecene biosynthesis in Fusarium and highlights the potential implication of various general regulatory circuits. Further studies on the role of these regulatory systems in the control of trichothecene biosynthesis might be useful in designing new strategies to reduce mycotoxin accumulation.
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Yli-Mattila T, Ward TJ, O'Donnell K, Proctor RH, Burkin AA, Kononenko GP, Gavrilova OP, Aoki T, McCormick SP, Gagkaeva TY. Fusarium sibiricum sp. nov, a novel type A trichothecene-producing Fusarium from northern Asia closely related to F. sporotrichioides and F. langsethiae. Int J Food Microbiol 2011; 147:58-68. [PMID: 21459470 DOI: 10.1016/j.ijfoodmicro.2011.03.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 03/04/2011] [Accepted: 03/07/2011] [Indexed: 11/27/2022]
Abstract
Production of type A trichothecenes has been reported in the closely related species Fusarium langsethiae and F. sporotrichioides. Here, we characterized a collection of Fusarium isolates from Siberia and the Russian Far East (hereafter Asian isolates) that produce high levels of the type A trichothecene T-2 toxin and are similar in morphology to the type A trichothecene-producing F. langsethiae, and to F. poae which often produces the type B trichothecene nivalenol. The Asian isolates possess unique macroscopic and microscopic characters and have a unique TG repeat in the nuclear ribosomal intergenic spacer (IGS rDNA) region. In Asian isolates, the TRI1-TRI16 locus, which determines type A versus type B trichothecene production in other species, is more similar in organization and sequence to the TRI1-TRI16 locus in F. sporotrichioides and F. langsethiae than to that in F. poae. Phylogenetic analysis of the TRI1 and TRI16 gene coding regions indicates that the genes in the Asian isolates are more closely related to those of F. sporotrichioides than F. langsethiae. Phylogenetic analysis of the beta-tubulin, translation elongation factor, RNA polymerase II and phosphate permease gene sequences resolved the Asian isolates into a well-supported sister lineage to F. sporotrichioides, with F. langsethiae forming a sister lineage to F. sporotrichioides and the Asian isolates. The Asian isolates are conspecific with Norwegian isolate IBT 9959 based on morphological and molecular analyses. In addition, the European F. langsethiae isolates from Finland and Russia were resolved into two distinct subgroups based on analyses of translation elongation factor and IGS rDNA sequences. Nucleotide polymorphisms within the IGS rDNA were used to design PCR primers that successfully differentiated the Asian isolates from F. sporotrichioides and F. langsethiae. Based on these data, we formally propose that the Asian isolates together with Norwegian isolate IBT 9959 comprise a novel phylogenetic species, F. sibiricum, while the two subgroups of F. langsethiae only represent intraspecific groups.
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Affiliation(s)
- Tapani Yli-Mattila
- Department of Biochemistry and Food Chemistry, University of Turku, FI-20014 Turku, Finland.
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Alexander NJ, McCormick SP, Waalwijk C, van der Lee T, Proctor RH. The genetic basis for 3-ADON and 15-ADON trichothecene chemotypes in Fusarium. Fungal Genet Biol 2011; 48:485-95. [PMID: 21216300 DOI: 10.1016/j.fgb.2011.01.003] [Citation(s) in RCA: 144] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 12/28/2010] [Accepted: 01/03/2011] [Indexed: 11/30/2022]
Abstract
Certain Fusarium species cause head blight of wheat and other small grains worldwide and produce trichothecene mycotoxins. These mycotoxins can induce toxicoses in animals and humans and can contribute to the ability of some fusaria to cause plant disease. Production of the trichothecene 3-acetyldeoxynivalenol (3-ADON) versus 15-acetyldeoxynivalenol (15-ADON) is an important phenotypic difference within and among some Fusarium species. However, until now, the genetic basis for this difference in chemotype has not been identified. Here, we identified consistent DNA sequence differences in the coding region of the trichothecene biosynthetic gene TRI8 in 3-ADON and 15-ADON strains. Functional analyses of the TRI8 enzyme (Tri8) in F. graminearum, the predominant cause of wheat head blight in North America and Europe, revealed that Tri8 from 3-ADON strains catalyzes deacetylation of the trichothecene biosynthetic intermediate 3,15-diacetyldeoxynivalenol at carbon 15 to yield 3-ADON, whereas Tri8 from 15-ADON strains catalyzes deacetylation of 3,15-diacetyldeoxynivalenol at carbon 3 to yield 15-ADON. Fusarium strains that produce the trichothecene nivalenol have a Tri8 that functions like that in 15-ADON strains. TRI3, which encodes a trichothecene carbon 15 acetyltransferase, was found to be functional in all three chemotypes. Together, our data indicate that differential activity of Tri8 determines the 3-ADON and 15-ADON chemotypes in Fusarium.
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Affiliation(s)
- Nancy J Alexander
- Bacterial Foodborne Pathogen and Mycology Research Unit, National Center for Agricultural Utilization Research, ARS, USDA, Peoria, IL 61604, USA.
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Proctor RH, McCormick SP, Alexander NJ, Desjardins AE. Evidence that a secondary metabolic biosynthetic gene cluster has grown by gene relocation during evolution of the filamentous fungus Fusarium. Mol Microbiol 2009; 74:1128-42. [PMID: 19843228 DOI: 10.1111/j.1365-2958.2009.06927.x] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Trichothecenes are terpene-derived secondary metabolites produced by multiple genera of filamentous fungi, including many plant pathogenic species of Fusarium. These metabolites are of interest because they are toxic to animals and plants and can contribute to pathogenesis of Fusarium on some crop species. Fusarium graminearum and F. sporotrichioides have trichothecene biosynthetic genes (TRI) at three loci: a 12-gene TRI cluster and two smaller TRI loci that consist of one or two genes. Here, comparisons of additional Fusarium species have provided evidence that TRI loci have a complex evolutionary history that has included loss, non-functionalization and rearrangement of genes as well as trans-species polymorphism. The results also indicate that the TRI cluster has expanded in some species by relocation of two genes into it from the smaller loci. Thus, evolutionary forces have driven consolidation of TRI genes into fewer loci in some fusaria but have maintained three distinct TRI loci in others.
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Affiliation(s)
- Robert H Proctor
- U. S. Department of Agriculture, Agricultural Research Service, National Center for Agricultural Utilization Research, Peoria, IL, USA.
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Alexander NJ, Proctor RH, McCormick SP. Genes, gene clusters, and biosynthesis of trichothecenes and fumonisins inFusarium. TOXIN REV 2009. [DOI: 10.1080/15569540903092142] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Garvey GS, McCormick SP, Alexander NJ, Rayment I. Structural and functional characterization of TRI3 trichothecene 15-O-acetyltransferase from Fusarium sporotrichioides. Protein Sci 2009; 18:747-61. [PMID: 19319932 DOI: 10.1002/pro.80] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Fusarium head blight is a devastating disease of cereal crops whose worldwide incidence is increasing and at present there is no satisfactory way of combating this pathogen or its associated toxins. There is a wide variety of trichothecene mycotoxins and they all contain a 12,13-epoxytrichothecene skeleton but differ in their substitutions. Indeed, there is considerable variation in the toxin profile across the numerous Fusarium species that has been ascribed to differences in the presence or absence of biosynthetic enzymes and their relative activity. This article addresses the source of differences in acetylation at the C15 position of the trichothecene molecule. Here, we present the in vitro structural and biochemical characterization of TRI3, a 15-O-trichothecene acetyltransferase isolated from F. sporotrichioides and the "in vivo" characterization of Deltatri3 mutants of deoxynivalenol (DON) producing F. graminearum strains. A kinetic analysis shows that TRI3 is an efficient enzyme with the native substrate, 15-decalonectrin, but is inactive with either DON or nivalenol. The structure of TRI3 complexed with 15-decalonectrin provides an explanation for this specificity and shows that Tri3 and Tri101 (3-O-trichothecene acetyltransferase) are evolutionarily related. The active site residues are conserved across all sequences for TRI3 orthologs, suggesting that differences in acetylation at C15 are not due to differences in Tri3. The tri3 deletion mutant shows that acetylation at C15 is required for DON biosynthesis even though DON lacks a C15 acetyl group. The enzyme(s) responsible for deacetylation at the 15 position of the trichothecene mycotoxins have not been identified.
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Affiliation(s)
- Graeme S Garvey
- Department of Biochemistry, University of Wisconsin, Madison, Wisconsin 53706, USA
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Bräse S, Encinas A, Keck J, Nising CF. Chemistry and Biology of Mycotoxins and Related Fungal Metabolites. Chem Rev 2009; 109:3903-90. [DOI: 10.1021/cr050001f] [Citation(s) in RCA: 411] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Stefan Bräse
- Institut für Organische Chemie,Karlsruhe Institute of Technology, Fritz-Haber-Weg 6, D-76131 Karlsruhe, Germany
| | - Arantxa Encinas
- Institut für Organische Chemie,Karlsruhe Institute of Technology, Fritz-Haber-Weg 6, D-76131 Karlsruhe, Germany
| | - Julia Keck
- Institut für Organische Chemie,Karlsruhe Institute of Technology, Fritz-Haber-Weg 6, D-76131 Karlsruhe, Germany
| | - Carl F. Nising
- Institut für Organische Chemie,Karlsruhe Institute of Technology, Fritz-Haber-Weg 6, D-76131 Karlsruhe, Germany
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Foroud NA, Eudes F. Trichothecenes in cereal grains. Int J Mol Sci 2009; 10:147-173. [PMID: 19333439 PMCID: PMC2662451 DOI: 10.3390/ijms10010147] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2008] [Revised: 12/16/2008] [Accepted: 01/05/2009] [Indexed: 12/22/2022] Open
Abstract
Trichothecenes are sesquiterpenoid mycotoxins associated with fusarium head blight (FHB) of cereals, with worldwide economic and health impacts. While various management strategies have been proposed to reduce the mycotoxin risk, breeding towards FHB-resistance appears to be the most effective means to manage the disease, and reduce trichothecene contamination of cereal-based food products. This review provides a brief summary of the trichothecene synthesis in Fusarium species, their toxicity in plants and humans, followed by the current methods of screening and breeding for resistance to FHB and trichothecene accumulation.
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Affiliation(s)
- Nora A. Foroud
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, 5403 1 Avenue South, Lethbridge, AB, Canada T1J 4B1. E-Mail:
- Michael Smith Laboratories, The University of British Columbia, #301 - 2185 East Mall, Vancouver, B.C., Canada V6T 1Z4
| | - François Eudes
- Lethbridge Research Centre, Agriculture and Agri-Food Canada, 5403 1 Avenue South, Lethbridge, AB, Canada T1J 4B1. E-Mail:
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A fumonisin biosynthetic gene cluster in Fusarium oxysporum strain O-1890 and the genetic basis for B versus C fumonisin production. Fungal Genet Biol 2008; 45:1016-26. [DOI: 10.1016/j.fgb.2008.02.004] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2008] [Revised: 02/13/2008] [Accepted: 02/14/2008] [Indexed: 11/21/2022]
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Alexander N. The TRI101 story: engineering wheat and barley to resist Fusarium head blight. WORLD MYCOTOXIN J 2008. [DOI: 10.3920/wmj2008.x004] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Fusarium head blight (FHB), caused primarily by Fusarium graminearum, is a major disease of wheat and barley in the United States and Canada. FHB epidemics have been on the increase since 1993 and have caused severe monetary damage for the growers and seed industry. Along with reduced yields, the presence of mycotoxins in moldy grain constitutes a major problem for the grain industry. These mycotoxins pose health hazards to humans and animals upon ingestion. The acute phytotoxicity of these mycotoxins and their occurrence in plant tissues correlates with their role in pathogenesis and the production of plant disease. Transgenic plants incorporating the Fusarium sporotrichioides Tri101 gene, a gene that reduces toxicity of trichothecenes, have reduced levels of disease, thus demonstrating that FHB severity and deoxynivalenol (DON) accumulation can be reduced in small grains by the introduction of a toxin-modification gene.
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Affiliation(s)
- N. Alexander
- Mycotoxin Research Unit, National Center for Agricultural Utilization Research, ARS, USDA, 1815 N. University Street, Peoria, IL 61604, USA
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36
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Hoffmeister D, Keller NP. Natural products of filamentous fungi: enzymes, genes, and their regulation. Nat Prod Rep 2007; 24:393-416. [PMID: 17390002 DOI: 10.1039/b603084j] [Citation(s) in RCA: 378] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We review the literature on the enzymes, genes, and whole gene clusters underlying natural product biosyntheses and their regulation in filamentous fungi. We have included literature references from 1958, yet the majority of citations are between 1995 and the present. A total of 295 references are cited.
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Affiliation(s)
- Dirk Hoffmeister
- Pharmaceutical Biology and Biotechnology, Albert-Ludwigs-University Freiburg, Stefan-Meier-Strasse 19, 79104 Freiburg, Germany.
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37
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McCormick SP, Alexander NJ, Proctor RH. Heterologous expression of two trichothecene P450 genes in Fusarium verticillioides. Can J Microbiol 2006; 52:220-6. [PMID: 16604118 DOI: 10.1139/w05-124] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Fusarium graminearum Z-3639 and F. sporotrichioides NRRL3299 produce the trichothecene mycotoxins 15-acetyldeoxynivalenol and T-2 toxin, respectively. These toxins differ in oxygenation at C-4, C-7, and C-8. In F. sporotrichioides, Tri1 (FsTri1) controls C-8 hydroxylation. To determine the function of an apparent F. graminearum Tri1 (FgTri1) homolog, both FsTri1 and FgTri1 genes were heterologously expressed in the trichothecene-nonproducing species F. verticillioides by fusing the Tri1 coding regions to the promoter of the fumonisin biosynthetic gene FUM8. FsTri1 and FgTri1 have been partially characterized by disruption analysis, and the results from these analyses suggest that FsTri1 most likely has a single function but that FgTri1 may have two functions. Transgenic F. verticillioides carrying the FsTri1 (FvF8FsTri1) converted exogenous isotrichodermin and calonectrin to 8-hydroxyisotrichodermin and 8-hydroxycalonectrin, respectively. Transgenic F. verticillioides carrying FgTri1 (FvF8FgTri1) converted isotrichodermin to a mixture of 7-hydroxyisotrichodermin and 8-hydroxyisotrichodermin but converted calonectrin to a mixture of 7-hydroxycalonectrin, 8-hydroxycalonectrin, and 3,15-diacetyldeoxynivalenol. A fourth compound, 7,8-dihydroxycalonectrin, was identified in large-scale F. verticillioides FvF8FgTri1 cultures fed isotrichodermin. Our results indicate that FgTri1 controls both C-7 and C-8 hydroxylation but that FsTri1 controls only C-8 hydroxylation. Our studies also demonstrate that F. verticillioides can metabolize some trichothecenes by adding an acetyl group to C-3 or by removing acetyl groups from C-4 or C-15. In addition, wild-type F. verticillioides can convert 7,8-dihydroxycalonectrin to 3,15-diacetyldeoxynivalenol.
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Affiliation(s)
- Susan P McCormick
- Mycotoxin Research Unit, USDA, ARS, National Center for Agricultural Utilization Research, IL 61604-3902, USA.
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Proctor RH, Desjardins AE, Brown DW, McCormick SP, Butchko RAE, Alexander N, Busman M. Biosynthesis ofFusarium mycotoxins and genomics ofFusarium verticillioides. Mycotoxin Res 2006; 22:75-8. [DOI: 10.1007/bf02956767] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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39
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Tokai T, Koshino H, Kawasaki T, Igawa T, Suzuki Y, Sato M, Fujimura M, Eizuka T, Watanabe H, Kitahara T, Ohta K, Shibata T, Kudo T, Inoue H, Yamaguchi I, Kimura M. Screening of putative oxygenase genes in theFusarium graminearumgenome sequence database for their role in trichothecene biosynthesis. FEMS Microbiol Lett 2005; 251:193-201. [PMID: 16125338 DOI: 10.1016/j.femsle.2005.07.043] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2005] [Revised: 07/28/2005] [Accepted: 07/30/2005] [Indexed: 11/27/2022] Open
Abstract
In the biosynthesis of type B trichothecenes, four oxygenation steps remain to have genes functionally assigned to them. On the basis of the complete genome sequence of Fusarium graminearum, expression patterns of all oxygenase genes were investigated in Fusarium asiaticum (F. graminearum lineage 6). As a result, we identified five cytochrome P450 monooxygenase (CYP) genes that are specifically expressed under trichothecene-producing conditions and are unique to the toxin-producing strains. The entire coding regions of four of these genes were identified in F. asiaticum. When expressed in Saccharomyces cerevisiae, none of the oxygenases were able to transform trichodiene-11-one to expected products. However, one of the oxygenases catalyzed the 2beta-hydroxylation rather than the expected 2alpha-hydroxylation. Targeted disruption of the five CYP genes did not alter the trichothecene profiles of F. asiaticum. The results are discussed in relation to the presence of as-yet-unidentified oxygenation genes that are necessary for the biosynthesis of trichothecenes.
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Affiliation(s)
- Takeshi Tokai
- Laboratory for Remediation Research, and Plant and Microbial Metabolic Engineering Unit-Laboratory, Plant Science Center (PSC1) and Discovery Research Institute, RIKEN, Wako, Saitama 351-0198, Japan
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Tokai T, Fujimura M, Inoue H, Aoki T, Ohta K, Shibata T, Yamaguchi I, Kimura M. Concordant evolution of trichothecene 3-O-acetyltransferase and an rDNA species phylogeny of trichothecene-producing and non-producing fusaria and other ascomycetous fungi. MICROBIOLOGY-SGM 2005; 151:509-519. [PMID: 15699200 DOI: 10.1099/mic.0.27435-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The cereal pathogen Fusarium graminearum species complex (e.g. Fusarium asiaticum, previously referred to as F. graminearum lineage 6) produces the mycotoxin trichothecene in infected grains. The fungus has a gene for self-defence, Tri101, which is responsible for 3-O-acetylation of the trichothecene skeleton in the biosynthetic pathway. Recently, trichothecene non-producers Fusarium oxysporum and Fusarium fujikuroi (teleomorph Gibberella fujikuroi) were shown to have both functional (Tri201) and non-functional (pseudo-Tri101) trichothecene 3-O-acetyltransferase genes in their genome. To gain insight into the evolution of the trichothecene genes in Gibberella species, the authors examined whether or not other (pseudo-)biosynthesis-related genes are found near Tri201. However, sequence analysis of a 12 kb region containing Tri201 did not result in identification of additional trichothecene (pseudo-)genes in F. oxysporum. In a further attempt to find other trichothecene (pseudo-)genes from the non-producer, the authors examined whether or not the non-trichothecene genes flanking the ends of the core trichothecene gene cluster (i.e. the Tri5 cluster) comprise a region of synteny in Gibberella species. However, it was not possible to isolate trichothecene (pseudo-)genes from F. oxysporum (in addition to the previously identified pseudo-Tri101), because synteny was not observed for this region in F. asiaticum and F. oxysporum. In contrast to this unsuccessful identification of additional trichothecene (pseudo-)genes in the non-producer, a functional trichothecene 3-O-acetyltransferase gene could be identified in fusaria other than Gibberella: Fusarium decemcellulare and Fusarium solani; and in an ascomycete from a different fungal genus, Magnaporthe grisea. Together with the recent functional identification of Saccharomyces cerevisiae ScAYT1, these results are suggestive of a different evolutionary origin for the trichothecene 3-O-acetyltransferase gene from other biosynthesis pathway genes. The phylogeny of the 3-O-acetyltransferase was mostly concordant with the rDNA species phylogeny of these ascomycetous fungi.
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Affiliation(s)
- Takeshi Tokai
- Laboratory of Genetics, Department of Regulation Biology, Faculty of Science, Saitama University, Saitama City, Saitama 338-8570, Japan
- Faculty of Life Science, Toyo University, Itakura, Gunma 374-0193, Japan
- Laboratory for Remediation Research, Plant Science Center, RIKEN, Wako, Saitama 351-0198, and Yokohama, Kanagawa 230-0045, Japan
| | - Makoto Fujimura
- Faculty of Life Science, Toyo University, Itakura, Gunma 374-0193, Japan
| | - Hirokazu Inoue
- Laboratory of Genetics, Department of Regulation Biology, Faculty of Science, Saitama University, Saitama City, Saitama 338-8570, Japan
| | - Takayuki Aoki
- Genetic Diversity Department, National Institute of Agrobiological Sciences (NIAS), Tsukuba, Ibaraki 305-8602, Japan
| | - Kunihiro Ohta
- Genetic Dynamics Research Unit Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
- Cellular and Molecular Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
| | - Takehiko Shibata
- Cellular and Molecular Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
| | - Isamu Yamaguchi
- Laboratory for Adaptation and Resistance, Plant Science Center, RIKEN, Yokohama, Kanagawa 230-0045, Japan
- Laboratory for Remediation Research, Plant Science Center, RIKEN, Wako, Saitama 351-0198, and Yokohama, Kanagawa 230-0045, Japan
| | - Makoto Kimura
- Genetic Dynamics Research Unit Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
- Cellular and Molecular Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
- Laboratory for Remediation Research, Plant Science Center, RIKEN, Wako, Saitama 351-0198, and Yokohama, Kanagawa 230-0045, Japan
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41
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McCormick SP, Harris LJ, Alexander NJ, Ouellet T, Saparno A, Allard S, Desjardins AE. Tri1 in Fusarium graminearum encodes a P450 oxygenase. Appl Environ Microbiol 2004; 70:2044-51. [PMID: 15066795 PMCID: PMC383062 DOI: 10.1128/aem.70.4.2044-2051.2004] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Gibberella zeae (asexual state Fusarium graminearum) is a major causal agent of wheat head blight and maize ear rot in North America and is responsible for contamination of grain with deoxynivalenol and related trichothecene mycotoxins. To identify additional trichothecene biosynthetic genes, cDNA libraries were prepared from fungal cultures under trichothecene-inducing conditions in culture and in planta. A gene designated LH1 that was highly expressed under these conditions exhibited only moderate (59%) similarity to known trichothecene biosynthetic cytochrome P450s. To determine the function of LH1, gene disruptants were produced and assessed for trichothecene production. Gene disruptants no longer produced 15-acetyldeoxynivalenol, which is oxygenated at carbon 7 (C-7) and C-8, but rather accumulated calonectrin and 3-deacetylcalonectrin, which are not oxygenated at either C-7 or C-8. These results indicate that gene LH1 encodes a cytochrome P450 responsible for oxygenation at one or both of these positions. Despite the relatively low level of DNA and amino acid sequence similarity between the two genes, LH1 from G. zeae is the probable homologue of Tri1, which encodes a cytochrome P450 required for C-8 oxygenation in F. sporotrichioides.
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Affiliation(s)
- S P McCormick
- Mycotoxin Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, U.S. Department of Agriculture, Peoria, Illinois 61604, USA.
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42
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Brown DW, Dyer RB, McCormick SP, Kendra DF, Plattner RD. Functional demarcation of the Fusarium core trichothecene gene cluster. Fungal Genet Biol 2004; 41:454-62. [PMID: 14998528 DOI: 10.1016/j.fgb.2003.12.002] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2003] [Accepted: 12/08/2003] [Indexed: 11/30/2022]
Abstract
Many Fusarium species produce toxic sesquiterpenoids known as trichothecenes, including deoxynivalenol and nivalenol by Fusarium graminearum and T-2 toxin by Fusarium sporotrichioides. These toxins are potent inhibitors of protein synthesis and are a significant agricultural problem due to their adverse affect on human, animal, and plant health. Previously, 10-12 co-regulated orthologous genes within a 26-kb region were identified in F. graminearum and F. sporotrichioides, respectively. A majority of these clustered genes have been shown to be involved in different aspects of trichothecene metabolism including 7 of 15 biosynthetic steps. Three other biosynthetic steps are carried out by genes located elsewhere in the genome. In this study, we sequenced 14-16 kb of DNA on both sides of the core clusters and identified 12 new ORFs in both Fusarium species. Although the predicted functions of some of the new ORFs are consistent with some unassigned biochemical reactions, gene expression and gene deletion studies indicate that none are required for trichothecene biosynthesis. These results provide evidence to demarcate both ends of the core trichothecene gene cluster. Index descriptors: Fungal secondary metabolite, Pathogenic fungi, Gene cluster, Fusarium, Trichothecene, DON
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Affiliation(s)
- Daren W Brown
- Mycotoxin Research Unit, USDA/ARS, National Center for Agricultural Utilization Research, Peoria, IL 61604, USA.
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