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Garg S, Nain P, Kumar A, Joshi S, Punetha H, Sharma PK, Siddiqui S, Alshaharni MO, Algopishi UB, Mittal A. Next generation plant biostimulants & genome sequencing strategies for sustainable agriculture development. Front Microbiol 2024; 15:1439561. [PMID: 39104588 PMCID: PMC11299335 DOI: 10.3389/fmicb.2024.1439561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2024] [Accepted: 06/25/2024] [Indexed: 08/07/2024] Open
Abstract
The best environment for plant growth and development contains certain essential metabolites. A broad category of metabolites known as "plant biostimulants" (PBs) includes biomolecules such as proteins, carbohydrates, lipids, and other secondary metabolites related to groups of terpenes, specific nitrogen-containing compounds, and benzene ring-conjugated compounds. The formation of biomolecules depends on both biotic and abiotic factors, such as the release of PB by plants, animals, and microorganisms, or it can result from the control of temperature, humidity, and pressure in the atmosphere, in the case of humic substances (HSs). Understanding the genomic outputs of the concerned organism (may be plants or others than them) becomes crucial for identifying the underlying behaviors that lead to the synthesis of these complex compounds. For the purposes of achieving the objectives of sustainable agriculture, detailed research on PBs is essential because they aid in increasing yield and other growth patterns of agro-economic crops. The regulation of homeostasis in the plant-soil-microbe system for the survival of humans and other animals is mediated by the action of plant biostimulants, as considered essential for the growth of plants. The genomic size and gene operons for functional and regulation control have so far been revealed through technological implementations, but important gene annotations are still lacking, causing a delay in revealing the information. Next-generation sequencing techniques, such as nanopore, nanoball, and Illumina, are essential in troubleshooting the information gaps. These technical advancements have greatly expanded the candidate gene openings. The secondary metabolites being important precursors need to be studied in a much wider scale for accurate calculations of biochemical reactions, taking place inside and outside the synthesized living cell. The present review highlights the sequencing techniques to provide a foundation of opportunity generation for agricultural sustainability.
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Affiliation(s)
- Shivanshu Garg
- Department of Biochemistry, CBSH-GBPUA&T, Pantnagar, India
| | - Pooja Nain
- Department of Soil Science, College of Agriculture, GBPUA&T, Pantnagar, India
| | - Ashish Kumar
- Department of Microbiology, CBSH-GBPUA&T, Pantnagar, India
| | - Samiksha Joshi
- School of Agriculture, Graphic Era Hill University, Bhimtal, India
| | | | - Pradeep Kumar Sharma
- Department of Environment Science, Graphic Era Deemed to be University, Dehradun, India
| | - Sazada Siddiqui
- Department of Biology, College of Science, King Khalid University, Abha, Saudi Arabia
| | | | | | - Amit Mittal
- School of Allied Sciences, Graphic Era Hill University, Bhimtal, India
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Armer VJ, Urban M, Ashfield T, Deeks MJ, Hammond-Kosack KE. The trichothecene mycotoxin deoxynivalenol facilitates cell-to-cell invasion during wheat-tissue colonization by Fusarium graminearum. MOLECULAR PLANT PATHOLOGY 2024; 25:e13485. [PMID: 38877764 PMCID: PMC11178975 DOI: 10.1111/mpp.13485] [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: 01/18/2024] [Revised: 05/19/2024] [Accepted: 05/22/2024] [Indexed: 06/16/2024]
Abstract
Fusarium head blight disease on small-grain cereals is primarily caused by the ascomycete fungal pathogen Fusarium graminearum. Infection of floral spike tissues is characterized by the biosynthesis and secretion of potent trichothecene mycotoxins, of which deoxynivalenol (DON) is widely reported due to its negative impacts on grain quality and consumer safety. The TRI5 gene encodes an essential enzyme in the DON biosynthesis pathway and the single gene deletion mutant, ΔTri5, is widely reported to restrict disease progression to the inoculated spikelet. In this study, we present novel bioimaging evidence revealing that DON facilitates the traversal of the cell wall through plasmodesmata, a process essential for successful colonization of host tissue. Chemical complementation of ΔTri5 did not restore macro- or microscopic phenotypes, indicating that DON secretion is tightly regulated both spatially and temporally. A comparative qualitative and quantitative morphological cellular analysis revealed infections had no impact on plant cell wall thickness. Immunolabelling of callose at plasmodesmata during infection indicates that DON can increase deposits when applied exogenously but is reduced when F. graminearum hyphae are present. This study highlights the complexity of the interconnected roles of mycotoxin production, cell wall architecture and plasmodesmata in this highly specialized interaction.
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Affiliation(s)
- Victoria J Armer
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, UK
- Biosciences, University of Exeter, Exeter, UK
| | - Martin Urban
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, UK
| | - Tom Ashfield
- Protecting Crops and the Environment, Rothamsted Research, Harpenden, UK
- Crop Health and Protection (CHAP), Rothamsted Research, Harpenden, UK
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Sharma S, Ahmed M, Akhter Y. Fungal acetyltransferases structures, mechanisms and inhibitors: A review. Int J Biol Macromol 2019; 157:626-640. [PMID: 31786301 DOI: 10.1016/j.ijbiomac.2019.11.214] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 11/26/2019] [Accepted: 11/26/2019] [Indexed: 12/31/2022]
Abstract
Acetylation of proteins is vital and mediate many processes within the cells like protein interactions, intercellular localization, protein stability, transcriptional regulation, enzyme activity and many more. Acetylation, an evolutionarily conserved process, attracted more attention due to its key regulatory role in many cellular processes and its effect on proteome and metabolome. In eukaryotes, protein acetylation also contribute to the epigenetic regulation of gene expression. Acetylation involves the transfer of acetyl group from donor acetyl coenzyme A to a suitable acceptor molecule and the reaction is catalyzed by acetyltransferase enzymes. The review focuses on current understanding of different acetyltransferase families: their discovery, structure and catalytic mechanism in fungal species. Fungal acetyltransferases use divergent catalytic mechanisms and carry out catalysis in a substrate-specific manner. The studies have explored different fungal acetyltransferases in relation to secondary metabolite production and the fungal pathogenesis. Although, the functions and catalytic mechanism of acetyltransferases are well known, however further enhanced knowledge may improve their utilization in various applications of biotechnology.
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Affiliation(s)
- Shikha Sharma
- School of Earth and Environmental Sciences, Central University of Himachal Pradesh, Shahpur, District-Kangra, Himachal Pradesh 176206, India
| | - Mushtaq Ahmed
- School of Earth and Environmental Sciences, Central University of Himachal Pradesh, Shahpur, District-Kangra, Himachal Pradesh 176206, India
| | - Yusuf Akhter
- Department of Biotechnology, Babasaheb Bhimrao Ambedkar University, VidyaVihar, Raebareli Road, Lucknow, Uttar Pradesh 226025, India.
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Knutsen HK, Alexander J, Barregård L, Bignami M, Brüschweiler B, Ceccatelli S, Cottrill B, Dinovi M, Grasl-Kraupp B, Hogstrand C, Hoogenboom LR, Nebbia CS, Oswald IP, Petersen A, Rose M, Roudot AC, Schwerdtle T, Vleminckx C, Vollmer G, Wallace H, De Saeger S, Eriksen GS, Farmer P, Fremy JM, Gong YY, Meyer K, Parent-Massin D, van Egmond H, Altieri A, Colombo P, Horváth Z, Levorato S, Edler L. Risk to human and animal health related to the presence of 4,15-diacetoxyscirpenol in food and feed. EFSA J 2018; 16:e05367. [PMID: 32626015 PMCID: PMC7009455 DOI: 10.2903/j.efsa.2018.5367] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
4,15‐Diacetoxyscirpenol (DAS) is a mycotoxin primarily produced by Fusarium fungi and occurring predominantly in cereal grains. As requested by the European Commission, the EFSA Panel on Contaminants in the Food Chain (CONTAM) assessed the risk of DAS to human and animal health related to its presence in food and feed. Very limited information was available on toxicity and on toxicokinetics in experimental and farm animals. Due to the limitations in the available data set, human acute and chronic health‐based guidance values (HBGV) were established based on data obtained in clinical trials of DAS as an anticancer agent (anguidine) after intravenous administration to cancer patients. The CONTAM Panel considered these data as informative for the hazard characterisation of DAS after oral exposure. The main adverse effects after acute and repeated exposure were emesis, with a no‐observed‐adverse‐effect level (NOAEL) of 32 μg DAS/kg body weight (bw), and haematotoxicity, with a NOAEL of 65 μg DAS/kg bw, respectively. An acute reference dose (ARfD) of 3.2 μg DAS/kg bw and a tolerable daily intake (TDI) of 0.65 μg DAS/kg bw were established. Based on over 15,000 occurrence data, the highest acute and chronic dietary exposures were estimated to be 0.8 and 0.49 μg DAS/kg bw per day, respectively, and were not of health concern for humans. The limited information for poultry, pigs and dogs indicated a low risk for these animals at the estimated DAS exposure levels under current feeding practices, with the possible exception of fattening chicken. Assuming similar or lower sensitivity than for poultry, the risk was considered overall low for other farm and companion animal species for which no toxicity data were available. In consideration of the similarities of several trichothecenes and the likelihood of co‐exposure via food and feed, it could be appropriate to perform a cumulative risk assessment for this group of substances.
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Venkataramana M, Selvakumar G, Chandranayaka S. Fusarium Mycotoxin: Toxicity and Detection. TOXINOLOGY 2018. [DOI: 10.1007/978-94-007-6449-1_4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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6
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Studt L, Janevska S, Arndt B, Boedi S, Sulyok M, Humpf HU, Tudzynski B, Strauss J. Lack of the COMPASS Component Ccl1 Reduces H3K4 Trimethylation Levels and Affects Transcription of Secondary Metabolite Genes in Two Plant-Pathogenic Fusarium Species. Front Microbiol 2017; 7:2144. [PMID: 28119673 PMCID: PMC5220078 DOI: 10.3389/fmicb.2016.02144] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 12/20/2016] [Indexed: 01/07/2023] Open
Abstract
In the two fungal pathogens Fusarium fujikuroi and Fusarium graminearum, secondary metabolites (SMs) are fitness and virulence factors and there is compelling evidence that the coordination of SM gene expression is under epigenetic control. Here, we characterized Ccl1, a subunit of the COMPASS complex responsible for methylating lysine 4 of histone H3 (H3K4me). We show that Ccl1 is not essential for viability but a regulator of genome-wide trimethylation of H3K4 (H3K4me3). Although, recent work in Fusarium and Aspergillus spp. detected only sporadic H3K4 methylation at the majority of the SM gene clusters, we show here that SM profiles in CCL1 deletion mutants are strongly deviating from the wild type. Cross-complementation experiments indicate high functional conservation of Ccl1 as phenotypes of the respective △ccl1 were rescued in both fungi. Strikingly, biosynthesis of the species-specific virulence factors gibberellic acid and deoxynivalenol produced by F. fujikuroi and F. graminearum, respectively, was reduced in axenic cultures but virulence was not attenuated in these mutants, a phenotype which goes in line with restored virulence factor production levels in planta. This suggests that yet unknown plant-derived signals are able to compensate for Ccl1 function during pathogenesis.
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Affiliation(s)
- Lena Studt
- Division of Microbial Genetics and Pathogen Interactions, Department of Applied Genetics and Cell Biology, BOKU-University of Natural Resources and Life SciencesVienna, Tulln an der Donau, Austria,Institute for Plant Biology and Biotechnology, Westfälische Wilhelms UniversityMünster, Germany,*Correspondence: Lena Studt, Joseph Strauss,
| | - Slavica Janevska
- Institute for Plant Biology and Biotechnology, Westfälische Wilhelms UniversityMünster, Germany
| | - Birgit Arndt
- Institute of Food Chemistry, Westfälische Wilhelms UniversityMünster, Germany
| | - Stefan Boedi
- Division of Microbial Genetics and Pathogen Interactions, Department of Applied Genetics and Cell Biology, BOKU-University of Natural Resources and Life SciencesVienna, Tulln an der Donau, Austria
| | - Michael Sulyok
- Center for Analytical Chemistry, Department IFA-Tulln, BOKU-University of Natural Resources and Life SciencesVienna, Tulln an der Donau, Austria
| | - Hans-Ulrich Humpf
- Institute of Food Chemistry, Westfälische Wilhelms UniversityMünster, Germany
| | - Bettina Tudzynski
- Institute for Plant Biology and Biotechnology, Westfälische Wilhelms UniversityMünster, Germany
| | - Joseph Strauss
- Division of Microbial Genetics and Pathogen Interactions, Department of Applied Genetics and Cell Biology, BOKU-University of Natural Resources and Life SciencesVienna, Tulln an der Donau, Austria,*Correspondence: Lena Studt, Joseph Strauss,
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7
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Abstract
Multiplex PCR is a powerful method to detect, identify, and quantify the mycotoxigenic fungus by targeting the amplification of genes associated with mycotoxin production and detection, identification, and quantification of Fusarium species. As compared with uniplex PCR, it has several advantages such as low cost, shortened time, and simultaneous amplification of more than two genes (in only one reaction tube). Here, we describe multiplex PCR-based detection and identification of trichothecene-, zearalenone-, fumonisin-, and enniatin-producing Fusarium species, the use of multiplex PCR in multiplex genotype assay and the use of multiplex TaqMan real-time qPCR.
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Affiliation(s)
- Tapani Yli-Mattila
- Molecular Plant Biology, Department of Biochemistry, University of Turku, FI-20520, Turku, Finland.
| | | | - Mudili Venkataramana
- Microbiology Division, DRDO-BU-Centre for Life sciences, Bharathiar University Campus, Coimbatore, 641046, TamilNadu, India
| | - Emre Yörük
- Department of Molecular Biology and Genetics, Faculty of Arts and Sciences, Istanbul Yeni Yuzyil University, 34010, Istanbul, Turkey
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Deepika VB, Murali TS, Satyamoorthy K. Modulation of genetic clusters for synthesis of bioactive molecules in fungal endophytes: A review. Microbiol Res 2015; 182:125-40. [PMID: 26686621 DOI: 10.1016/j.micres.2015.10.009] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 10/21/2015] [Accepted: 10/26/2015] [Indexed: 11/26/2022]
Abstract
Novel drugs with unique and targeted mode of action are very much need of the hour to treat and manage severe multidrug infections and other life-threatening complications. Though natural molecules have proved to be effective and environmentally safe, the relative paucity of discovery of new drugs has forced us to lean towards synthetic chemistry for developing novel drug molecules. Plants and microbes are the major resources that we rely upon in our pursuit towards discovery of novel compounds of pharmacological importance with less toxicity. Endophytes, an eclectic group of microbes having the potential to chemically bridge the gap between plants and microbes, have attracted the most attention due to their relatively high metabolic versatility. Since continuous large scale supply of major metabolites from microfungi and especially endophytes is severely impeded by the phenomenon of attenuation in axenic cultures, the major challenge is to understand the regulatory mechanisms in operation that drive the expression of metabolic gene clusters of pharmaceutical importance. This review is focused on the major regulatory elements that operate in filamentous fungi and various combinatorial multi-disciplinary approaches involving bioinformatics, molecular biology, and metabolomics that could aid in large scale synthesis of important lead molecules.
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Affiliation(s)
- V B Deepika
- Division of Biotechnology, School of Life Sciences, Manipal University, Manipal 576104, India
| | - T S Murali
- Division of Biotechnology, School of Life Sciences, Manipal University, Manipal 576104, India.
| | - K Satyamoorthy
- Division of Biotechnology, School of Life Sciences, Manipal University, Manipal 576104, India
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9
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SnPKS19 Encodes the Polyketide Synthase for Alternariol Mycotoxin Biosynthesis in the Wheat Pathogen Parastagonospora nodorum. Appl Environ Microbiol 2015; 81:5309-17. [PMID: 26025896 DOI: 10.1128/aem.00278-15] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 05/20/2015] [Indexed: 12/12/2022] Open
Abstract
Alternariol (AOH) is an important mycotoxin from the Alternaria fungi. AOH was detected for the first time in the wheat pathogen Parastagonospora nodorum in a recent study. Here, we exploited reverse genetics to demonstrate that SNOG_15829 (SnPKS19), a close homolog of Penicillium aethiopicum norlichexanthone (NLX) synthase gene gsfA, is required for AOH production. We further validate that SnPKS19 is solely responsible for AOH production by heterologous expression in Aspergillus nidulans. The expression profile of SnPKS19 based on previous P. nodorum microarray data correlated with the presence of AOH in vitro and its absence in planta. Subsequent characterization of the ΔSnPKS19 mutants showed that SnPKS19 and AOH are not involved in virulence and oxidative stress tolerance. Identification and characterization of the P. nodorum SnPKS19 cast light on a possible alternative AOH synthase gene in Alternaria alternata and allowed us to survey the distribution of AOH synthase genes in other fungal genomes. We further demonstrate that phylogenetic analysis could be used to differentiate between AOH synthases and the closely related NLX synthases. This study provides the basis for studying the genetic regulation of AOH production and for development of molecular diagnostic methods for detecting AOH-producing fungi in the future.
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10
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Crespo-Sempere A, Estiarte N, Marín S, Sanchis V, Ramos AJ. Targeting Fusarium graminearum control via polyamine enzyme inhibitors and polyamine analogs. Food Microbiol 2015; 49:95-103. [PMID: 25846919 DOI: 10.1016/j.fm.2015.01.020] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Revised: 01/11/2015] [Accepted: 01/31/2015] [Indexed: 11/29/2022]
Abstract
Fusarium graminearum not only reduces yield and seed quality but also constitutes a risk to public or animal health owing to its ability to contaminate grains with mycotoxins. Resistance problems are emerging and control strategies based on new targets are needed. Polyamines have a key role in growth, development and differentiation. In this work, the possibility of using polyamine metabolism as a target to control F. graminearum has been assessed. It was found that putrescine induces mycotoxin production, correlating with an over expression of TRI5 and TRI6 genes. In addition, a homolog of the Saccharomyces cerevisiae TPO4 involved in putrescine excretion was up-regulated as putrescine concentration increased while DUR3 and SAM3 homologues, involved in putrescine uptake, were down-regulated. When 2.5 mM D, l-α-difluoromethylornithine (DFMO) was added to the medium, DON production decreased from 3.2 to 0.06 ng/mm(2) of colony and growth was lowered by up to 70 per cent. However, exogenous putrescine could overcome DFMO effects. Five polyamine transport inhibitors were also tested against F. graminearum. AMXT-1505 was able to completely inhibit in vitro growth and DON production. Additionally, AMXT-1505 blocked F. graminearum growth in inoculated wheat spikes reducing DON mycotoxin contamination from 76.87 μg/g to 0.62 μg/g.
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Affiliation(s)
- A Crespo-Sempere
- Applied Mycology Unit, Food Technology Department, University of Lleida, UTPV-XaRTA, Agrotecnio Center, Av. Rovira Roure 191, 25198 Lleida, Spain.
| | - N Estiarte
- Applied Mycology Unit, Food Technology Department, University of Lleida, UTPV-XaRTA, Agrotecnio Center, Av. Rovira Roure 191, 25198 Lleida, Spain
| | - S Marín
- Applied Mycology Unit, Food Technology Department, University of Lleida, UTPV-XaRTA, Agrotecnio Center, Av. Rovira Roure 191, 25198 Lleida, Spain
| | - V Sanchis
- Applied Mycology Unit, Food Technology Department, University of Lleida, UTPV-XaRTA, Agrotecnio Center, Av. Rovira Roure 191, 25198 Lleida, Spain
| | - A J Ramos
- Applied Mycology Unit, Food Technology Department, University of Lleida, UTPV-XaRTA, Agrotecnio Center, Av. Rovira Roure 191, 25198 Lleida, Spain
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11
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Cacho RA, Tang Y, Chooi YH. Next-generation sequencing approach for connecting secondary metabolites to biosynthetic gene clusters in fungi. Front Microbiol 2015; 5:774. [PMID: 25642215 PMCID: PMC4294208 DOI: 10.3389/fmicb.2014.00774] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 12/17/2014] [Indexed: 12/20/2022] Open
Abstract
Genomics has revolutionized the research on fungal secondary metabolite (SM) biosynthesis. To elucidate the molecular and enzymatic mechanisms underlying the biosynthesis of a specific SM compound, the important first step is often to find the genes that responsible for its synthesis. The accessibility to fungal genome sequences allows the bypass of the cumbersome traditional library construction and screening approach. The advance in next-generation sequencing (NGS) technologies have further improved the speed and reduced the cost of microbial genome sequencing in the past few years, which has accelerated the research in this field. Here, we will present an example work flow for identifying the gene cluster encoding the biosynthesis of SMs of interest using an NGS approach. We will also review the different strategies that can be employed to pinpoint the targeted gene clusters rapidly by giving several examples stemming from our work.
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Affiliation(s)
- Ralph A Cacho
- Chemical and Biomolecular Engineering Department, University of California Los Angeles, Los Angeles, CA, USA
| | - Yi Tang
- Chemical and Biomolecular Engineering Department, University of California Los Angeles, Los Angeles, CA, USA ; Chemistry and Biochemistry Department, University of California Los Angeles, Los Angeles, CA, USA
| | - Yit-Heng Chooi
- Plant Sciences Division, Research School of Biology, The Australian National University Canberra, ACT, Australia
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12
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Abstract
Mycotoxins are natural contaminants of food and feed products, posing a substantial health risk to humans and animals throughout the world. A plethora of filamentous fungi has been identified as mycotoxin producers and most of these fungal species belong to the genera Aspergillus, Fusarium, and Penicillium. A number of studies have been conducted to better understand the molecular mechanisms of biosynthesis of key mycotoxins and the regulatory cascades controlling toxigenesis. In many cases, the mycotoxin biosynthetic genes are clustered and regulated by one or more pathway-specific transcription factor(s). In addition, as biosynthesis of many secondary metabolites is coordinated with fungal growth and development, there are a number of upstream regulators affecting biosynthesis of mycotoxins in fungi. This review presents a concise summary of the regulation of mycotoxin biosynthesis, focusing on the roles of the upstream regulatory elements governing biosynthesis of aflatoxin and sterigmatocystin in Aspergillus.
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Affiliation(s)
| | - Jae-Hyuk Yu
- University of Wisconsin-Madison, Madison, Wisconsin, USA
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13
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Kawaide H. Biochemical and Molecular Analyses of Gibberellin Biosynthesis in Fungi. Biosci Biotechnol Biochem 2014; 70:583-90. [PMID: 16556972 DOI: 10.1271/bbb.70.583] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The plant hormone, gibberellin (GA), regulates plant growth and development. It was first isolated as a superelongation-promoting diterpenoid from the fungus, Gibberella fujikuroi. G. fujikuroi uses different GA biosynthetic intermediates from those in plants to produce GA3. Another class of GA-producing fungus, Phaeosphaeria sp. L487, synthesizes GA1 by using the same intermediates as those in plants. A molecular analysis of GA biosynthesis in Phaeosphaeria sp. has revealed that diterpene cyclase and cytochrome P450 monooxygenases were involved in the plant-like biosynthesis of GA1. Fungal ent-kaurene synthase is a bifunctional cyclase. Subsequent oxidation steps are catalyzed by P450s, leading to biologically active GA1. GA biosynthesis in plants is divided into three steps involving soluble enzymes and membrane-bound cytochrome P450. The activation of plant GAs is catalyzed by soluble 2-oxoglutarate-dependent dioxygenases, which is in contrast to the catalysis of fungal GA biosynthesis. This difference suggests that the origin of fungal GA biosynthesis is evolutionally independent of that in plants.
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Affiliation(s)
- Hiroshi Kawaide
- Division of Agriscience and Bioscience, Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology (TUAT), Tokyo, Japan.
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14
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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: 272] [Impact Index Per Article: 27.2] [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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15
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Foroud NA, Chatterton S, Reid LM, Turkington TK, Tittlemier SA, Gräfenhan T. Fusarium Diseases of Canadian Grain Crops: Impact and Disease Management Strategies. Fungal Biol 2014. [DOI: 10.1007/978-1-4939-1188-2_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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16
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Strategies for mining fungal natural products. J Ind Microbiol Biotechnol 2013; 41:301-13. [PMID: 24146366 DOI: 10.1007/s10295-013-1366-3] [Citation(s) in RCA: 133] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 10/05/2013] [Indexed: 10/26/2022]
Abstract
Fungi are well known for their ability to produce a multitude of natural products. On the one hand their potential to provide beneficial antibiotics and immunosuppressants has been maximized by the pharmaceutical industry to service the market with cost-efficient drugs. On the other hand identification of trace amounts of known mycotoxins in food and feed samples is of major importance to ensure consumer health and safety. Although several fungal natural products, their biosynthesis and regulation are known today, recent genome sequences of hundreds of fungal species illustrate that the secondary metabolite potential of fungi has been substantially underestimated. Since expression of genes and subsequent production of the encoded metabolites are frequently cryptic or silent under standard laboratory conditions, strategies for activating these hidden new compounds are essential. This review will cover the latest advances in fungal genome mining undertaken to unlock novel products.
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McCormick SP, Price NPJ, Kurtzman CP. Glucosylation and other biotransformations of T-2 toxin by yeasts of the trichomonascus clade. Appl Environ Microbiol 2012; 78:8694-702. [PMID: 23042183 PMCID: PMC3502904 DOI: 10.1128/aem.02391-12] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 10/01/2012] [Indexed: 11/20/2022] Open
Abstract
Trichothecenes are sesquiterpenoid toxins produced by Fusarium species. Since these mycotoxins are very stable, there is interest in microbial transformations that can remove toxins from contaminated grain or cereal products. Twenty-three yeast species assigned to the Trichomonascus clade (Saccharomycotina, Ascomycota), including four Trichomonascus species and 19 anamorphic species presently classified in Blastobotrys, were tested for their ability to convert the trichothecene T-2 toxin to less-toxic products. These species gave three types of biotransformations: acetylation to 3-acetyl T-2 toxin, glycosylation to T-2 toxin 3-glucoside, and removal of the isovaleryl group to form neosolaniol. Some species gave more than one type of biotransformation. Three Blastobotrys species converted T-2 toxin into T-2 toxin 3-glucoside, a compound that has been identified as a masked mycotoxin in Fusarium-infected grain. This is the first report of a microbial whole-cell method for producing trichothecene glycosides, and the potential large-scale availability of T-2 toxin 3-glucoside will facilitate toxicity testing and development of methods for detection of this compound in agricultural and other products.
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Affiliation(s)
- Susan P McCormick
- Bacterial Foodborne Pathogens and Mycology Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, U.S. Department of Agriculture, Peoria, Illinois, USA.
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18
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Involvement of Trichoderma trichothecenes in the biocontrol activity and induction of plant defense-related genes. Appl Environ Microbiol 2012; 78:4856-68. [PMID: 22562989 DOI: 10.1128/aem.00385-12] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Trichoderma species produce trichothecenes, most notably trichodermin and harzianum A (HA), by a biosynthetic pathway in which several of the involved proteins have significant differences in functionality compared to their Fusarium orthologues. In addition, the genes encoding these proteins show a genomic organization differing from that of the Fusarium tri clusters. Here we describe the isolation of Trichoderma arundinaceum IBT 40837 transformants which have a disrupted or silenced tri4 gene, a gene encoding a cytochrome P450 monooxygenase that oxygenates trichodiene to give rise to isotrichodiol, and the effect of tri4 gene disruption and silencing on the expression of other tri genes. Our results indicate that the tri4 gene disruption resulted in a reduced antifungal activity against Botrytis cinerea and Rhizoctonia solani and also in a reduced ability to induce the expression of tomato plant defense-related genes belonging to the salicylic acid (SA) and jasmonate (JA) pathways against B. cinerea, in comparison to the wild-type strain, indicating that HA plays an important function in the sensitization of Trichoderma-pretreated plants against this fungal pathogen. Additionally, the effect of the interaction of T. arundinaceum with B. cinerea or R. solani and with tomato seedlings on the expressions of the tri genes was studied.
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19
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Merhej J, Urban M, Dufresne M, Hammond-Kosack KE, Richard-Forget F, Barreau C. The velvet gene, FgVe1, affects fungal development and positively regulates trichothecene biosynthesis and pathogenicity in Fusarium graminearum. MOLECULAR PLANT PATHOLOGY 2012; 13:363-74. [PMID: 22013911 PMCID: PMC6638759 DOI: 10.1111/j.1364-3703.2011.00755.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Trichothecenes are a group of toxic secondary metabolites produced mainly by Fusarium graminearum (teleomorph: Gibberella zeae) during the infection of crop plants, including wheat, maize, barley, oats, rye and rice. Some fungal genes involved in trichothecene biosynthesis have been shown to encode regulatory proteins. However, the global regulation of toxin biosynthesis is still enigmatic. In addition to the production of secondary metabolites belonging to the trichothecene family, F. graminearum produces the red pigment aurofusarin. The gene regulation underlying the production of aurofusarin is not well understood. The velvet gene (veA) is conserved in various genera of filamentous fungi. Recently, the veA gene from Aspergillus nidulans has been shown to be the key component of the velvet complex regulating development and secondary metabolism. Using blast analyses, we identified the velvet gene from F. graminearum, FgVe1. Disruption of FgVe1 causes several phenotypic effects. However, the complementation of this mutant with the FgVe1 gene restores the wild-type phenotypes. The in vitro phenotypes include hyperbranching of the mycelium, suppression of aerial hyphae formation, reduced hydrophobicity of the mycelium and highly reduced sporulation. Our data also show that FgVe1 modulates the production of the aurofusarin pigment and is essential for the expression of Tri genes and the production of trichothecenes. Pathogenicity studies performed on flowering wheat plants indicate that FgVe1 is a positive regulator of virulence in F. graminearum.
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Affiliation(s)
- Jawad Merhej
- INRA, UR1264 MycSA, 71, Avenue Edouard Bourleaux, BP81, F-33883 Villenave d'Ornon, France
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20
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Bin-Umer MA, McLaughlin JE, Basu D, McCormick S, Tumer NE. Trichothecene mycotoxins inhibit mitochondrial translation--implication for the mechanism of toxicity. Toxins (Basel) 2011; 3:1484-501. [PMID: 22295173 PMCID: PMC3268453 DOI: 10.3390/toxins3121484] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Revised: 11/18/2011] [Accepted: 11/18/2011] [Indexed: 11/16/2022] Open
Abstract
Fusarium head blight (FHB) reduces crop yield and results in contamination of grains with trichothecene mycotoxins. We previously showed that mitochondria play a critical role in the toxicity of a type B trichothecene. Here, we investigated the direct effects of type A and type B trichothecenes on mitochondrial translation and membrane integrity in Saccharomyces cerevisiae. Sensitivity to trichothecenes increased when functional mitochondria were required for growth, and trichothecenes inhibited mitochondrial translation at concentrations, which did not inhibit total translation. In organello translation in isolated mitochondria was inhibited by type A and B trichothecenes, demonstrating that these toxins have a direct effect on mitochondrial translation. In intact yeast cells trichothecenes showed dose-dependent inhibition of mitochondrial membrane potential and reactive oxygen species, but only at doses higher than those affecting mitochondrial translation. These results demonstrate that inhibition of mitochondrial translation is a primary target of trichothecenes and is not secondary to the disruption of mitochondrial membranes.
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Affiliation(s)
- Mohamed Anwar Bin-Umer
- Department of Plant Biology and Pathology, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, NJ 08901, USA; (M.A.B.-U.); (J.E.M.); (D.B.)
| | - John E. McLaughlin
- Department of Plant Biology and Pathology, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, NJ 08901, USA; (M.A.B.-U.); (J.E.M.); (D.B.)
| | - Debaleena Basu
- Department of Plant Biology and Pathology, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, NJ 08901, USA; (M.A.B.-U.); (J.E.M.); (D.B.)
| | - Susan McCormick
- Bacterial Foodborne Pathogens and Mycology Unit, National Center for Agricultural Utilization Research, United States Department of Agriculture, Agricultural Research Service, Peoria, IL 61604, USA;
| | - Nilgun E. Tumer
- Department of Plant Biology and Pathology, School of Environmental and Biological Sciences, Rutgers University, New Brunswick, NJ 08901, USA; (M.A.B.-U.); (J.E.M.); (D.B.)
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21
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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: 300] [Impact Index Per Article: 23.1] [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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22
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McCormick SP, Hohn TM. Accumulation of Trichothecenes in Liquid Cultures of a Fusarium sporotrichioides Mutant Lacking a Functional Trichothecene C-15 Hydroxylase. Appl Environ Microbiol 2010; 63:1685-8. [PMID: 16535589 PMCID: PMC1389144 DOI: 10.1128/aem.63.5.1685-1688.1997] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A mutant strain of Fusarium sporotrichioides NRRL 3299 produced by disruption of Tri11, a gene encoding a cytochrome P-450 monooxygenase, was shown to be altered in its ability to biosynthesize T-2 toxin. This mutant strain produced four trichothecenes that were not observed in cultures of the parent strain. The compounds were identified as isotrichodermin, 8-hydroxyisotrichodermin, 8-hydroxyisotrichodermol, and 3,4,8-trihydroxytricothecene on the basis of their nuclear magnetic resonance and mass spectra. This is the first report of these 8-hydroxytrichothecenes as metabolites of F. sporotrichioides. The accumulation of isotrichodermin and the results of whole-cell feeding experiments with a Tri11(sup-) strain confirm that oxygenation of C-15 is blocked.
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23
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Merhej J, Boutigny A, Pinson-Gadais L, Richard-Forget F, Barreau C. Acidic pH as a determinant ofTRIgene expression and trichothecene B biosynthesis inFusarium graminearum. Food Addit Contam Part A Chem Anal Control Expo Risk Assess 2010; 27:710-7. [DOI: 10.1080/19440040903514531] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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24
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Aguileta G, Lengelle J, Marthey S, Chiapello H, Rodolphe F, Gendrault A, Yockteng R, Vercken E, Devier B, Fontaine MC, Wincker P, Dossat C, Cruaud C, Couloux A, Giraud T. Finding candidate genes under positive selection in Non-model species: examples of genes involved in host specialization in pathogens. Mol Ecol 2009; 19:292-306. [PMID: 20041992 DOI: 10.1111/j.1365-294x.2009.04454.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Numerous genes in diverse organisms have been shown to be under positive selection, especially genes involved in reproduction, adaptation to contrasting environments, hybrid inviability, and host-pathogen interactions. Looking for genes under positive selection in pathogens has been a priority in efforts to investigate coevolution dynamics and to develop vaccines or drugs. To elucidate the functions involved in host specialization, here we aimed at identifying candidate sequences that could have evolved under positive selection among closely related pathogens specialized on different hosts. For this goal, we sequenced c. 17,000-32,000 ESTs from each of four Microbotryum species, which are fungal pathogens responsible for anther smut disease on host plants in the Caryophyllaceae. Forty-two of the 372 predicted orthologous genes showed significant signal of positive selection, which represents a good number of candidate genes for further investigation. Sequencing 16 of these genes in 9 additional Microbotryum species confirmed that they have indeed been rapidly evolving in the pathogen species specialized on different hosts. The genes showing significant signals of positive selection were putatively involved in nutrient uptake from the host, secondary metabolite synthesis and secretion, respiration under stressful conditions and stress response, hyphal growth and differentiation, and regulation of expression by other genes. Many of these genes had transmembrane domains and may therefore also be involved in pathogen recognition by the host. Our approach thus revealed fruitful and should be feasible for many non-model organisms for which candidate genes for diversifying selection are needed.
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Affiliation(s)
- G Aguileta
- Ecologie, Systématique et Evolution, Université Paris-Sud, F-91405 Orsay cedex, France
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25
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Gardiner DM, Kazan K, Manners JM. Novel genes of Fusarium graminearum that negatively regulate deoxynivalenol production and virulence. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2009; 22:1588-1600. [PMID: 19888824 DOI: 10.1094/mpmi-22-12-1588] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Fusarium head blight of wheat, caused by Fusarium graminearum, is a serious disease resulting in both reduced yields and contamination of grain with trichothecene toxins, with severe consequences for mammalian health. Recently, we have identified several related amine compounds such as agmatine and putrescine that promote the production of high levels of trichothecene toxins, such as deoxynivalenol (DON), in culture by F. graminearum and F. sporotrichioides. Here, a global analysis of fungal gene expression using the Affymetrix Fusarium GeneChip during culture under DON-inducing conditions compared with noninducing conditions is reported. Agmatine differentially regulated a large number of fungal genes, including both known and previously uncharacterized putative secondary metabolite biosynthetic gene clusters. In silico prediction of binding sites for the transcriptional regulator (TRI6) controlling TRI gene expression and gene expression analysis in a TRI6 mutant of F. graminearum showed that three of the differentially regulated genes were under the control of TRI6. Gene knock-out mutations of two of these genes resulted in mutants with massively increased production of DON and increased aggressiveness toward wheat. Our results not only identify a novel mechanism of negative regulation of DON production and virulence in F. graminearum but also point out the potential of this pathogen to evolve with an ability to produce massively increased amounts of toxins and increased virulence.
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Affiliation(s)
- Donald M Gardiner
- CSIRO Plant Industry, Queensland Bioscience Precinct, 306 Carmody Road, St. Lucia, Queensland 4067, Australia.
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26
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Koster B, Wong B, Straus N, Malloch D. A multi-gene phylogeny for Stachybotrys evidences lack of trichodiene synthase (tri5) gene for isolates of one of three intrageneric lineages. ACTA ACUST UNITED AC 2009; 113:877-86. [DOI: 10.1016/j.mycres.2009.04.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2008] [Revised: 02/19/2009] [Accepted: 04/21/2009] [Indexed: 11/16/2022]
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27
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Gardiner DM, Kazan K, Manners JM. Nutrient profiling reveals potent inducers of trichothecene biosynthesis in Fusarium graminearum. Fungal Genet Biol 2009; 46:604-13. [DOI: 10.1016/j.fgb.2009.04.004] [Citation(s) in RCA: 194] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Revised: 04/17/2009] [Accepted: 04/19/2009] [Indexed: 11/25/2022]
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28
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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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29
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Desjardins AE. From yellow rain to green wheat: 25 years of trichothecene biosynthesis research. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2009; 57:4478-4484. [PMID: 19385595 DOI: 10.1021/jf9003847] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Trichothecene biosynthesis research at the U.S. Department of Agriculture in Peoria, IL, began in 1984 in response to concerns about the use of trichothecenes in biological warfare, but continued as a long-term research program on the intractable problem of trichothecene contamination of human foods and animal feeds. Over 25 years, the trichothecene biosynthesis research group integrated natural product chemistry with fungal genetics and plant pathology in the laboratory and in the field to understand how and why Fusarium species make these complex and highly toxic metabolites. This interdisciplinary research placed trichothecenes in the unique class of fungal metabolites that not only cause mycotoxicoses in animals but also are virulence factors in plant disease.
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Affiliation(s)
- Anne E Desjardins
- US Department of Agriculture, Mycotoxin Research, National Center for Agricultural Utilization Research, Agricultural Research Service, Peoria, Illinois 61604, USA.
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30
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Alexander NJ, McCormick SP, Blackburn JA. Effects of xanthotoxin treatment on trichothecene production in Fusarium sporotrichioides. Can J Microbiol 2009; 54:1023-31. [PMID: 19096457 DOI: 10.1139/w08-100] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
There are 4 P450 oxygenases involved in the biosynthesis of T-2 toxin in Fusarium sporotrichioides. Exactly how these enzymes react to antimicrobial plant defense compounds is unknown. Xanthotoxin (8-methoxypsoralen) is a phototoxic furanocoumarin that acts as a P450 oxygenase inhibitor. The current study shows that the addition of concentrations of 1.0 mmol/L or less of xanthotoxin to liquid cultures of F. sporotrichioides NRRL3299 can effectively block T-2 toxin production and cause an increase in accumulation of trichodiene, the hydrocarbon precursor of trichothecenes. The addition of xanthotoxin to liquid cultures of a trichodiene-accumulating F. sporotrichioides Tri4- mutant caused a 3- to 10-fold increase in trichodiene accumulation, suggesting that xanthotoxin not only blocks trichothecene oxygenation reactions, but may in some way also promote the synthesis of trichodiene. Feeding studies showed that 2 of the 4 P450 oxygenases, TRI4 and TRI1, were more sensitive to xanthotoxin, while oxygenases TRI11 and TRI13 were unaffected. Quantitative reverse-transcriptase PCR indicated that several of the genes in the toxin biosynthetic pathway were upregulated by xanthotoxin, with Tri4 showing the highest increase in expression. These results indicate that while xanthotoxin inhibits specific P450 oxygenase activity, it also has an effect on gene expression.
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Affiliation(s)
- Nancy J Alexander
- Mycotoxin Research Unit, National Center for Agricultural Utilization Research, ARS/USDA, 1815 N. University St, Peoria, IL61604, USA.
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31
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Lysøe E, Bone KR, Klemsdal SS. Real-time quantitative expression studies of the zearalenone biosynthetic gene cluster in Fusarium graminearum. PHYTOPATHOLOGY 2009; 99:176-84. [PMID: 19159310 DOI: 10.1094/phyto-99-2-0176] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The estrogenic mycotoxin zearalenone (ZON) produced by some Fusarium spp. causes reproductive problems and hyperestrogenic syndromes in mammals. In an effort to elucidate the molecular pathways of ZON production, we present a comparative real-time quantitative polymerase chain reaction expression study of seven contiguous genes in the ZON biosynthetic cluster on sterile rice and during wheat and oat infection. Under ZON production on rice, the polyketide synthase (PKS) genes PKS4 and PKS13, alcohol oxidase FG12056 gene, and transcriptional regulator FG02398 gene showed similarly upregulated patterns, whereas the nonribosomal peptide synthetase (NPS) FG02394, the K(+) channel beta subunit FG12015, and the protein kinase FG02399 displayed a variant pattern. During the same time period under wheat infection when no ZON was produced, the PKS genes and the NPS were downregulated relative to rice whereas the K(+) channel beta subunit gene FG12015 was markedly upregulated, suggesting that it may play a role in the infection process. This is the first expression study of ZON biosynthetic genes in planta. The results give insight into the regulation and activities of the ZON gene cluster under different experimental systems and suggest a connection between ZON and a K(+) channel that could reveal a novel function for ZON in Fusarium spp.
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Affiliation(s)
- Erik Lysøe
- Plant Health and Plant Protection Division, Bioforsk-Norwegian Institute for Agricultural and Environmental Research, Høgskoleveien 7, N-1432 As, Norway
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32
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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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33
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Developing Aspergillus as a host for heterologous expression. Biotechnol Adv 2009; 27:53-75. [DOI: 10.1016/j.biotechadv.2008.09.001] [Citation(s) in RCA: 204] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Revised: 09/04/2008] [Accepted: 09/07/2008] [Indexed: 12/11/2022]
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34
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Wang JH, Li HP, Qu B, Zhang JB, Huang T, Chen FF, Liao YC. Development of a generic PCR detection of 3-acetyldeoxy-nivalenol-, 15-acetyldeoxynivalenol- and nivalenol-chemotypes of Fusarium graminearum Clade. Int J Mol Sci 2008; 9:2495-2504. [PMID: 19330088 PMCID: PMC2635647 DOI: 10.3390/ijms9122495] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2008] [Revised: 11/20/2008] [Accepted: 12/03/2008] [Indexed: 11/16/2022] Open
Abstract
Fusarium graminearum clade pathogens cause Fusarium head blight (FHB) or scab of wheat and other small cereal grains, producing different kinds of trichothecene mycotoxins that are detrimental to human and domestic animals. Type B trichothecene mycotoxins such as deoxynivalenol, 3-acetyldeoxynivalenol (3-AcDON), 15-acetyldeoxynivalenol (15-AcDON) and nivalenol (NIV) are the principal Fusarium mycotoxins reported in China, as well as in other countries. A genomic polymerase chain reaction (PCR) to predict chemotypes was developed based on the structural gene sequences of Tri13 genes involved in trichothecene mycotoxin biosynthesis pathways. A single pair of primers derived from the Tri13 genes detected a 583 bp fragment from 15-AcDON-chemotypes, a 644 bp fragment from 3-AcDON-chemotypes and an 859 bp fragment from NIV-producing strains. Fusarium strains from China, Nepal, USA and Europe were identified by this method, revealing their mycotoxin chemotypes identical to that obtained by chemical analyses of HPLC or GC/MS and other PCR assays. The mycotoxin chemotype-specific fragments were amplified from a highly variable region located in Tri13 genes with three deletions for 15-AcDON-chemotypes, two deletions for 3-AcDON-chemotypes and no deletion for NIV-producers. This PCR assay generated a single amplicon and thus should be more reliable than other PCR-based assays that showed the absence or presence of a PCR fragment since these assays may generate false-negative results. The results with strains from several different countries as well as from different hosts further indicated that this method should be globally applicable. This is a rapid, reliable and cost-effective method for the identification of type B trichothecene mycotoxin chemotypes in Fusarium species and food safety controls.
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Affiliation(s)
- Jian-Hua Wang
- Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, P.R. China. E-Mails:
(J. W);
(H. L.);
(B. Q);
(J. Z.);
(T. H);
(F. C)
| | - He-Ping Li
- Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, P.R. China. E-Mails:
(J. W);
(H. L.);
(B. Q);
(J. Z.);
(T. H);
(F. C)
| | - Bo Qu
- Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, P.R. China. E-Mails:
(J. W);
(H. L.);
(B. Q);
(J. Z.);
(T. H);
(F. C)
| | - Jing-Bo Zhang
- Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, P.R. China. E-Mails:
(J. W);
(H. L.);
(B. Q);
(J. Z.);
(T. H);
(F. C)
| | - Tao Huang
- Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, P.R. China. E-Mails:
(J. W);
(H. L.);
(B. Q);
(J. Z.);
(T. H);
(F. C)
| | - Fang-Fang Chen
- Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, P.R. China. E-Mails:
(J. W);
(H. L.);
(B. Q);
(J. Z.);
(T. H);
(F. C)
| | - Yu-Cai Liao
- Molecular Biotechnology Laboratory of Triticeae Crops, Huazhong Agricultural University, Wuhan 430070, P.R. China. E-Mails:
(J. W);
(H. L.);
(B. Q);
(J. Z.);
(T. H);
(F. C)
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, P.R. China
- Author to whom correspondence should be addressed; E-Mails:
;
; Fax: +86-27-87283008
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35
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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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Niessen L. PCR-based diagnosis and quantification of mycotoxin-producing fungi. ADVANCES IN FOOD AND NUTRITION RESEARCH 2008; 54:81-138. [PMID: 18291305 DOI: 10.1016/s1043-4526(07)00003-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Mycotoxins are secondary metabolites produced by filamentous fungi which have toxicologically relevant effects on vertebrates if administered in small doses via a natural route. In order to improve food safety and to protect consumers from harmful contaminants, the presence of fungi with the potential to produce such compounds must be checked at critical control points during the production of agricultural commodities as well as during the process of food and feed preparation. Polymerase chain reaction (PCR)-based diagnosis has been applied as an alternative assay replacing cumbersome and time-consuming microbiological and chemical methods for the detection and identification of the most serious toxin producers in the fungal genera Fusarium, Aspergillus, and Penicillium. The current chapter covers the numerous PCR-based assays which have been published since the first description of the use of this technology to detect Aspergillus flavus biosynthesis genes in 1996.
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Affiliation(s)
- Ludwig Niessen
- Technische Universität München, Lehrstuhl für Technische Mikrobiologie, Weihenstephaner Steig 16, D-85350 Freising, Germany
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37
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Ochiai N, Tokai T, Takahashi-Ando N, Fujimura M, Kimura M. Genetically engineeredFusariumas a tool to evaluate the effects of environmental factors on initiation of trichothecene biosynthesis. FEMS Microbiol Lett 2007; 275:53-61. [PMID: 17711459 DOI: 10.1111/j.1574-6968.2007.00869.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Fusarium graminearum was engineered for expression of enhanced green fluorescent protein gene (egfp) as a reporter regulated in a manner similar to Tri5, a key pathway gene in trichothecene biosynthesis. Using the transgenic fungus, it was found that the reporter gene was induced to express in aerial hyphae developed on trichothecene noninducing medium YG solidified by agar. Unexpectedly, the transcriptional activation of egfp was markedly suppressed by adding NaCl that does not significantly affect fungal growth. As suggested by these findings, wild-type F. graminearum that formed aerial hyphae on YG agar plates produced trichothecenes and the production was effectively suppressed by adding 1% NaCl to the agar. To evaluate the effects of abiotic stress on the expression of trichothecene biosynthesis (Tri) genes, a sensitive plate assay was established using GYEP medium (which very weakly induces trichothecene production) solidified with gellan gum. Using this assay, triazole fungicides were shown to cause transcriptional activation of egfp at sublethal concentrations. Indeed, trichothecene production significantly increased when F. graminearum was grown in rice medium (which moderately induces trichothecene) amended with low doses of tebuconazole. The real-time monitoring system described here may help predict the risks of trichothecene contamination by the fungus under various environmental conditions.
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Affiliation(s)
- Noriyuki Ochiai
- Plant & Microbial Metabolic Engineering Research Unit, Discovery Research Institute, RIKEN, Saitama, Japan
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39
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Schollenberger M, Drochner W, Müller HM. Fusarium toxins of the scirpentriol subgroup: a review. Mycopathologia 2007; 164:101-18. [PMID: 17610049 DOI: 10.1007/s11046-007-9036-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2007] [Accepted: 06/06/2007] [Indexed: 11/28/2022]
Abstract
Scirpentriol and its seven acetylated derivatives comprise a family of type-A trichothecene toxins produced by several species of Fusarium fungi. Out of this group 4,15-diacetoxyscirpenol has attracted most attention. It elicits toxic responses in several species and was detected in a variety of substrates. Out of the three possible monoacetylated derivatives 15-monoacetoxyscirpenol and the parent alcohol scirpentriol received some attention, whereas the remaining members of the family were mentioned in few reports. The present review deals with the structure, biosynthesis, analysis and toxicity of scirpentriol toxins. Formation by Fusarium species as well as culture conditions used for toxigenicity studies are reviewed; data about the natural occurrence of scirpentriol toxins in different cereal types, cereal associated products as well as in non-grain matrices including potato and soya bean are reported. Basing on literature reports about the toxicity of scirpentriol toxins an attempt is made to summarise the state of knowledge for risk evaluation for human and animal health.
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Affiliation(s)
- Margit Schollenberger
- Institute of Animal Nutrition, Hohenheim University, Emil-Wolff-Str. 10, 70599, Stuttgart, Germany.
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40
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Chen H, Lee MH, Daub ME, Chung KR. Molecular analysis of the cercosporin biosynthetic gene cluster in Cercospora nicotianae. Mol Microbiol 2007; 64:755-70. [PMID: 17462021 DOI: 10.1111/j.1365-2958.2007.05689.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We describe a core gene cluster, comprised of eight genes (designated CTB1-8), and associated with cercosporin toxin production in Cercospora nicotianae. Sequence analysis identified 10 putative open reading frames (ORFs) flanking the previously characterized CTB1 and CTB3 genes that encode, respectively, the polyketide synthase and a dual methyltransferase/monooxygenase required for cercosporin production. Expression of eight of the genes was co-ordinately induced under cercosporin-producing conditions and was regulated by the Zn(II)Cys(6) transcriptional activator, CTB8. Expression of the genes, affected by nitrogen and carbon sources and pH, was also controlled by another transcription activator, CRG1, previously shown to regulate cercosporin production and resistance. Disruption of the CTB2 gene encoding a methyltransferase or the CTB8 gene yielded mutants that were completely defective in cercosporin production and inhibitory expression of the other CTB cluster genes. Similar 'feedback' transcriptional inhibition was observed when the CTB1, or CTB3 but not CTB4 gene was inactivated. Expression of four ORFs located on the two distal ends of the cluster did not correlate with cercosporin biosynthesis and did not show regulation by CTB8, suggesting that the biosynthetic cluster was limited to CTB1-8. A biosynthetic pathway and a regulatory network leading to cercosporin formation are proposed.
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Affiliation(s)
- Huiqin Chen
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences (IFAS), University of Florida, 700 Experiment Station Road, Lake Alfred, FL 33850, USA
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41
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Dekkers KL, You BJ, Gowda VS, Liao HL, Lee MH, Bau HJ, Ueng PP, Chung KR. The Cercospora nicotianae gene encoding dual O-methyltransferase and FAD-dependent monooxygenase domains mediates cercosporin toxin biosynthesis. Fungal Genet Biol 2007; 44:444-54. [PMID: 17074519 DOI: 10.1016/j.fgb.2006.08.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Revised: 08/28/2006] [Accepted: 08/30/2006] [Indexed: 11/27/2022]
Abstract
Cercosporin, a photo-activated, non-host-selective phytotoxin produced by many species of the plant pathogenic fungus Cercospora, causes peroxidation of plant cell membranes by generating reactive oxygen species and is an important virulence determinant. Here we report a new gene, CTB3 that is involved in cercosporin biosynthesis in Cercospora nicotianae. CTB3 is adjacent to a previously identified CTB1 encoding a polyketide synthase which is also required for cercosporin production. CTB3 contains a putative O-methyltransferase domain in the N-terminus and a putative flavin adenine dinucleotide (FAD)-dependent monooxygenase domain in the C-terminus. The N-terminal amino acid sequence also is similar to that of the transcription enhancer AFLS (formerly AFLJ) involved in aflatoxin biosynthesis. Expression of CTB3 was differentially regulated by light, medium, nitrogen and carbon sources and pH. Disruption of the N- or C-terminus of CTB3 yielded mutants that failed to accumulate the CTB3 transcript and cercosporin. The Deltactb3 disruptants produced a yellow pigment that is not toxic to tobacco suspension cells. Production of cercosporin in a Deltactb3 null mutant was fully restored when transformed with a functional CTB3 clone or when paired with a Deltactb1-null mutant (defective in polyketide synthase) by cross feeding of the biosynthetic intermediates. Pathogenicity assays using detached tobacco leaves revealed that the Deltactb3 disruptants drastically reduced lesion formation.
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Affiliation(s)
- Katherine L Dekkers
- Citrus Research and Education Center, Institute of Food and Agricultural Sciences (IFAS), University of Florida, 700 Experiment Station Rd., Lake Alfred, FL 33850, USA
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42
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The Trichothecenes and Their Biosynthesis. PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS 2007. [DOI: 10.1007/978-3-211-49389-2_2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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43
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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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44
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Hewald S, Linne U, Scherer M, Marahiel MA, Kämper J, Bölker M. Identification of a gene cluster for biosynthesis of mannosylerythritol lipids in the basidiomycetous fungus Ustilago maydis. Appl Environ Microbiol 2006; 72:5469-77. [PMID: 16885300 PMCID: PMC1538720 DOI: 10.1128/aem.00506-06] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Many microorganisms produce surface-active substances that enhance the availability of water-insoluble substrates. Although many of these biosurfactants have interesting potential applications, very little is known about their biosynthesis. The basidiomycetous fungus Ustilago maydis secretes large amounts of mannosylerythritol lipids (MELs) under conditions of nitrogen starvation. We recently described a putative glycosyltransferase, Emt1, which is essential for MEL biosynthesis and whose expression is strongly induced by nitrogen limitation. We used DNA microarray analysis to identify additional genes involved in MEL biosynthesis. Here we show that emt1 is part of a gene cluster which comprises five open reading frames. Three of the newly identified proteins, Mac1, Mac2, and Mat1, contain short sequence motifs characteristic for acyl- and acetyltransferases. Mutational analysis revealed that Mac1 and Mac2 are essential for MEL production, which suggests that they are involved in the acylation of mannosylerythritol. Deletion of mat1 resulted in the secretion of completely deacetylated MELs, as determined by mass spectrometry. We overexpressed Mat1 in Escherichia coli and demonstrated that this enzyme acts as an acetyl coenzyme A-dependent acetyltransferase. Remarkably, Mat1 displays relaxed regioselectivity and is able to acetylate mannosylerythritol at both the C-4 and C-6 hydroxyl groups. Based on these results, we propose a biosynthesis pathway for the generation of mannosylerythritol lipids in U. maydis.
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Affiliation(s)
- Sandra Hewald
- Fachbereich Biologie, Philipps-Universität Marburg, 35032 Marburg, Germany
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45
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Brodhagen M, Keller NP. Signalling pathways connecting mycotoxin production and sporulation. MOLECULAR PLANT PATHOLOGY 2006; 7:285-301. [PMID: 20507448 DOI: 10.1111/j.1364-3703.2006.00338.x] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
SUMMARY Mycotoxin contamination of food and feed presents a serious food safety issue on a global scale, causing tremendous yield and economic losses. These toxins, produced largely by members of the genera Aspergillus and Fusarium, represent a subset of the impressive array of secondary metabolites produced by filamentous fungi. Some secondary metabolites are associated temporally and functionally with sporulation. In Aspergillus and Fusarium, sporulation and mycotoxin production are both regulated by G protein signalling pathways. G protein signalling pathways commonly regulate fungal development, stress response and expression of virulence traits. In addition, fungal development is influenced by external factors. Among these are lipids, and in particular, oxylipin signals, which may be derived from either the fungus or infected seeds. Regardless of origin, oxylipins have the potential to elicit profound changes in both sporulation and mycotoxin production in the fungus. Signal transduction via G protein signalling pathways represents one mechanism by which oxylipin signals might elicit these changes. Therefore, in this review we integrate discussion of oxylipin signals and of G protein signalling cascades as regulators of fungal development.
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Affiliation(s)
- Marion Brodhagen
- Department of Plant Pathology, University of Wisconsin-Madison, 1630 Linden Dr, Madison, WI 53706-1598, USA
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46
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Siewers V, Kokkelink L, Smedsgaard J, Tudzynski P. Identification of an abscisic acid gene cluster in the grey mold Botrytis cinerea. Appl Environ Microbiol 2006; 72:4619-26. [PMID: 16820452 PMCID: PMC1489360 DOI: 10.1128/aem.02919-05] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Like several other phytopathogenic fungi, the ascomycete Botrytis cinerea is known to produce the plant hormone abscisic acid (ABA) in axenic culture. Recently, bcaba1, the first fungal gene involved in ABA biosynthesis, was identified. Neighborhood analysis of bcaba1 revealed three further candidate genes of this pathway: a putative P450 monooxygenase-encoding gene (bcaba2), an open reading frame without significant similarities (bcaba3), and a gene probably coding for a short-chain dehydrogenase/reductase (bcaba4). Targeted inactivation of the genes proved the involvement of BcABA2 and BcABA3 in ABA biosynthesis and suggested a contribution of BcABA4. The close linkage of at least three ABA biosynthetic genes is strong evidence for the presence of an abscisic acid gene cluster in B. cinerea.
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Affiliation(s)
- Verena Siewers
- Westf. Wilhelms-Universität Münster, Institut für Botanik, Schlossgarten 3, 48149 Münster, Germany
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47
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Desjardins AE, Plattner RD, Stessman RJ, McCormick SP, Millard MJ. Identification and heritability of fumonisin insensitivity in Zea mays. PHYTOCHEMISTRY 2005; 66:2474-80. [PMID: 16198380 DOI: 10.1016/j.phytochem.2005.08.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2005] [Revised: 07/12/2005] [Indexed: 05/04/2023]
Abstract
Landraces of maize (Zea mays ssp. mays) and its wild teosinte relatives (Zea mays spp. parviglumis and mexicana) were surveyed for sensitivity to fumonisin B(1), a phytotoxin produced by the maize pathogen Gibberella moniliformis. Only two of 42 Z. mays samples were highly insensitive to FB(1) (ED(50) = ca. 200 microM). The teosintes and 76% of the maize landraces were moderately or highly sensitive to FB(1) (ED(50) < or = 30 microM), which indicates that FB(1) sensitivity is likely to be an ancestral trait in Z. mays. F(1) generations derived from crosses between FB(1)-sensitive maize inbred B73 and insensitive landraces were significantly less sensitive than B73. Thus, our data indicate that FB(1)-insensitivity is a relatively rare but heritable trait in maize. We also report the sensitivity of maize to other Gibberella toxins - beauvericin, diacetoxyscirpenol, and moniliformin.
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Affiliation(s)
- Anne E Desjardins
- National Center for Agricultural Utilization Research, United States Department of Agriculture, Peoria, IL 61604, USA.
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48
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Schultze K, Schimek C, Wöstemeyer J, Burmester A. Sexuality and parasitism share common regulatory pathways in the fungus Parasitella parasitica. Gene 2005; 348:33-44. [PMID: 15777660 DOI: 10.1016/j.gene.2005.01.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2003] [Revised: 11/27/2004] [Accepted: 01/06/2005] [Indexed: 11/16/2022]
Abstract
Parasitella parasitica, a facultative mycoparasite of zygomycetous fungi, forms cytoplasmic fusions with its hosts during infection. Thus, the organism is an efficient donor of genetic material in parasexual host-parasite interactions. Recognition between parasite and host is mediated by trisporoids, which are also responsible for sexual communication. The TDH gene for one of the key enzymes of trisporic acid biosynthesis, 4-dihydromethyl-trisporate dehydrogenase, was cloned and its transcription analysed. TDH was cloned on a 6175-bp insert and was found to map in a complex cluster of genes that suggest post-transcriptional antisense regulation. Histochemical TDH analysis in developing parasitic or sexual structures shows high enzymatic activity in Parasitella. TDH is linked to a gene for a putative acyl-CoA thioesterase (ACT). Two ORFs were identified in the 5'-region of the TDH gene, a third one, coding for 176 amino acids overlaps the ACT gene in antisense direction completely. Expression levels of ACT and ORF1 depend on parasitic and sexual interactions.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- Blotting, Northern
- Cloning, Molecular
- DNA, Fungal/chemistry
- DNA, Fungal/genetics
- Fatty Acids, Unsaturated/biosynthesis
- Fungal Proteins/genetics
- Fungal Proteins/metabolism
- Gene Expression Regulation, Fungal
- Genes, Fungal/genetics
- Genetic Linkage
- Molecular Sequence Data
- Mucorales/genetics
- Mucorales/growth & development
- Mucorales/metabolism
- Open Reading Frames/genetics
- Oxidoreductases/genetics
- Oxidoreductases/metabolism
- Palmitoyl-CoA Hydrolase/genetics
- Poly A/genetics
- RNA, Fungal/genetics
- RNA, Fungal/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Sequence Homology, Nucleic Acid
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Affiliation(s)
- Kornelia Schultze
- Institute for Microbiology, Friedrich-Schiller-Universität Jena, Chair of General Microbiology and Microbe Genetics, Neugasse 24, D-07743 Jena, Germany
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49
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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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50
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Abstract
Fungal secondary metabolites are of intense interest to humankind due to their pharmaceutical (antibiotics) and/or toxic (mycotoxins) properties. In the past decade, tremendous progress has been made in understanding the genes that are associated with production of various fungal secondary metabolites. Moreover, the regulatory mechanisms controlling biosynthesis of diverse groups of secondary metabolites have been unveiled. In this review, we present the current understanding of the genetic regulation of secondary metabolism from clustering of biosynthetic genes to global regulators balancing growth, sporulation, and secondary metabolite production in selected fungi with emphasis on regulation of metabolites of agricultural concern. Particularly, the roles of G protein signaling components and developmental regulators in the mycotoxin sterigmatocystin biosynthesis in the model fungus Aspergillus nidulans are discussed in depth.
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Affiliation(s)
- Jae-Hyuk Yu
- Department of Food Microbiology and Toxicology, University of Wisconsin, Madison, Wisconsin 53706, USA.
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