E-Mail Alert

Add your e-mail address to receive forthcoming issues of this journal:

Journal Browser

Journal Browser

Special Issue "Trichothecenes"

Quicklinks

A special issue of Toxins (ISSN 2072-6651). This special issue belongs to the section "Mycotoxins".

Deadline for manuscript submissions: closed (31 May 2011)

Special Issue Editors

Guest Editor
Dr. Nancy Alexander

Bacterial Foodborne Pathogen and Mycology Research Unit, National Center for Agricultural Utilization Research, 1815 N. University St. Peoria, IL 61604, USA
Guest Editor
Dr. Susan McCormick

Bacterial Foodborne Pathogen and Mycology Research Unit, National Center for Agricultural Utilization Research, 1815 N. University St. Peoria, IL 61604, USA

Special Issue Information

Dear Colleagues,

With a growing population, access to a safe food supply and a safe environment for all consumers 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. Many of the molds that are plant pathogens produce trichothecene mycotoxins, which are known to cause serious human and animal toxicoses.  Development of methods to detect and reduce trichothecenes in the field, as well as the food supply, is based upon basic research in a number of areas. This special issue of Toxins is devoted to recent advances in trichothecene research. Topics of interest include the biosynthesis of trichothecenes in organisms such as Fusarium graminearum, F. sporotrichioides, F. culmorum, and other related species and genera such as Trichoderma, Trichothecium and Stachybotrys; genetics and biology of the fungi producing trichothecenes, including phytotoxicity and animal toxicology; detection methods for trichothecenes; phylogenetic studies of trichothecene-producing fungi; and other pertinent topics.

Dr. Nancy Alexander
Dr. Susan McCormick
Guest Editors

Keywords

  • mycotoxins
  • trichothecenes
  • fungal pathogens
  • Fusarium
  • plant pathogens
  • mycotoxin detection
  • fungal phylogenetics
  • mycotoxin biosynthesis

Published Papers (11 papers)

View options order results:
result details:
Displaying articles 1-11
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle Observation of T-2 Toxin and HT-2 Toxin Glucosides from Fusarium sporotrichioides by Liquid Chromatography Coupled to Tandem Mass Spectrometry (LC-MS/MS)
Toxins 2011, 3(12), 1554-1568; doi:10.3390/toxins3121554
Received: 24 November 2011 / Revised: 14 December 2011 / Accepted: 19 December 2011 / Published: 20 December 2011
Cited by 30 | PDF Full-text (482 KB) | HTML Full-text | XML Full-text
Abstract
The trichothecenes produced by solid and liquid cultures of Fusarium sporotrichioides were evaluated with high performance liquid chromatography—tandem mass spectrometry (LC-MS/MS). Along with the expected T-2 toxin HT-2 toxin and neosolaniol, two additional compounds were detected, which had ions 162 m/z higher [...] Read more.
The trichothecenes produced by solid and liquid cultures of Fusarium sporotrichioides were evaluated with high performance liquid chromatography—tandem mass spectrometry (LC-MS/MS). Along with the expected T-2 toxin HT-2 toxin and neosolaniol, two additional compounds were detected, which had ions 162 m/z higher than those in the mass spectra of T-2 toxin or HT-2 toxin. Fragmentation behavior of these two compounds was similar to that of T-2 toxin and HT-2 toxin. Based on LC-MS/MS behavior, it is proposed that the two compounds are T-2 toxin 3-O-glucoside and HT-2 toxin 3-O-glucoside. Production of the two glucosides was measured in kernels from wheat and oat inoculated with F. sporotrichiodes, as well as in cultures grown in liquid media and on cracked corn or rice. Production of glucosides in wheat and oats suggest that they may also be present in naturally contaminated cereals. Full article
(This article belongs to the Special Issue Trichothecenes)
Figures

Open AccessArticle Trichothecene Mycotoxins Inhibit Mitochondrial Translation—Implication for the Mechanism of Toxicity
Toxins 2011, 3(12), 1484-1501; doi:10.3390/toxins3121484
Received: 14 September 2011 / Revised: 18 November 2011 / Accepted: 18 November 2011 / Published: 2 December 2011
Cited by 17 | PDF Full-text (1277 KB) | HTML Full-text | XML Full-text
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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Trichothecenes)
Open AccessArticle Role of Fungicides, Application of Nozzle Types, and the Resistance Level of Wheat Varieties in the Control of Fusarium Head Blight and Deoxynivalenol
Toxins 2011, 3(11), 1453-1483; doi:10.3390/toxins3111453
Received: 1 October 2011 / Revised: 3 November 2011 / Accepted: 3 November 2011 / Published: 16 November 2011
Cited by 14 | PDF Full-text (553 KB) | HTML Full-text | XML Full-text
Abstract
Fungicide application is a key factor in the control of mycotoxin contamination in the harvested wheat grain. However, the practical results are often disappointing. In 2000–2004, 2006–2008 and 2007 and 2008, three experiments were made to test the efficacy of fungicide control [...] Read more.
Fungicide application is a key factor in the control of mycotoxin contamination in the harvested wheat grain. However, the practical results are often disappointing. In 2000–2004, 2006–2008 and 2007 and 2008, three experiments were made to test the efficacy of fungicide control on Fusarium Head Blight (FHB) in wheat and to find ways to improve control of the disease and toxin contamination. In a testing system we have used for 20 years, tebuconazole and tebuconazole + prothioconazole fungicides regularly reduced symptoms by about 80% with a correlating reduction in toxin contamination. Averages across the years normally show a correlation of r = 0.90 or higher. The stability differences (measured by the stability index) between the poorest and the best fungicides are about 10 or more times, differing slightly in mycotoxin accumulation, FHB index (severity) and Fusarium damaged kernels (FDK). The weak fungicides, like carbendazim, were effective only when no epidemic occurred or epidemic severity was at a very low level. Similar fungicide effects were seen on wheat cultivars which varied in FHB resistance. In this study, we found three fold differences in susceptibility to FHB between highly susceptible and moderately resistant cultivars when treated with fungicides. In the moderately resistant cultivars, about 50% of the fungicide treatments lowered the DON level below the regulatory limit. In the most susceptible cultivars, all fungicides failed to reduce mycotoxin levels low enough for grain acceptance, in spite of the fact that disease was significantly reduced. The results correlated well with the results of the large-scale field tests of fungicide application at the time of natural infection. The Turbo FloodJet nozzle reduced FHB incidence and DON contamination when compared to the TeeJet XR nozzle. Overall, the data suggest that significant decreases in FHB incidence and deoxynivalenol contamination in field situations are possible with proper fungicide applications. Additionally, small plot tests can be used to evaluate the quality of the field disease and toxin production. Full article
(This article belongs to the Special Issue Trichothecenes)
Open AccessArticle Genetic Diversity in Fusarium graminearum from a Major Wheat-Producing Region of Argentina
Toxins 2011, 3(10), 1294-1309; doi:10.3390/toxins3101294
Received: 6 July 2011 / Revised: 19 August 2011 / Accepted: 30 September 2011 / Published: 20 October 2011
Cited by 15 | PDF Full-text (612 KB) | HTML Full-text | XML Full-text
Abstract
The Fusarium graminearum species complex (FGSC) is a group of mycotoxigenic fungi that are the primary cause of Fusarium head blight (FHB) of wheat worldwide. The distribution, frequency of occurrence, and genetic diversity of FGSC species in cereal crops in South America [...] Read more.
The Fusarium graminearum species complex (FGSC) is a group of mycotoxigenic fungi that are the primary cause of Fusarium head blight (FHB) of wheat worldwide. The distribution, frequency of occurrence, and genetic diversity of FGSC species in cereal crops in South America is not well understood compared to some regions of Asia, Europe and North America. Therefore, we examined the frequency and genetic diversity of a collection of 183 FGSC isolates recovered from wheat grown during multiple growing seasons and across a large area of eastern Argentina, a major wheat producing region in South America. Sequence analysis of the translation elongation factor 1−α and β-tubulin genes as well as Amplified Fragment Length Polymorphism (AFLP) analyses indicated that all isolates were the FGSC species F. graminearum sensu stricto. AFLP analysis resolved at least 11 subgroups, and all the isolates represented different AFLP haplotypes. AFLP profile and geographic origin were not correlated. Previously obtained trichothecene production profiles of the isolates revealed that the 15-acetyldeoxynivalenol chemotype was slightly more frequent than the 3-acetyldeoxynivalenol chemotype among the isolates. These data extend the current understanding of FGSC diversity and provide further evidence that F. graminearum sensu stricto is the predominant cause of FHB in the temperate main wheat-growing area of Argentina. Moreover, two isolates of F. crookwellense and four of F. pseudograminearum were also recovered from wheat samples and sequenced. The results also suggest that, although F. graminearum sensu stricto was the only FGSC species recovered in this study, the high level of genetic diversity within this species should be considered in plant breeding efforts and development of other disease management strategies aimed at reducing FHB. Full article
(This article belongs to the Special Issue Trichothecenes)
Open AccessArticle Overexpression of the Trichoderma brevicompactum tri5 Gene: Effect on the Expression of the Trichodermin Biosynthetic Genes and on Tomato Seedlings
Toxins 2011, 3(9), 1220-1232; doi:10.3390/toxins3091220
Received: 7 September 2011 / Revised: 15 September 2011 / Accepted: 21 September 2011 / Published: 23 September 2011
Cited by 14 | PDF Full-text (509 KB) | HTML Full-text | XML Full-text
Abstract
Trichoderma brevicompactum IBT 40841 produces trichodermin, a trichothecene-type toxin that shares most of the steps of its biosynthesis with harzianum A, another trichothecene produced by several Trichoderma species. The first specific step in the trichothecene biosynthesis is carried out by a terpene [...] Read more.
Trichoderma brevicompactum IBT 40841 produces trichodermin, a trichothecene-type toxin that shares most of the steps of its biosynthesis with harzianum A, another trichothecene produced by several Trichoderma species. The first specific step in the trichothecene biosynthesis is carried out by a terpene cylcase, trichodiene synthase, that catalyzes the conversion of farnesyl pyrophosphate to trichodiene and that is encoded by the tri5 gene. Overexpression of tri5 resulted in increased levels of trichodermin production, but also in an increase in tyrosol and hydroxytyrosol production, two antioxidant compounds that may play a regulatory role in trichothecene biosynthesis, and also in a higher expression of three trichothecene genes, tri4, tri6 and tri10, and of the erg1 gene, which participates in the synthesis of triterpenes. The effect of tri5 overexpression on tomato seedling disease response was also studied. Full article
(This article belongs to the Special Issue Trichothecenes)
Open AccessArticle Incidence of Fusarium Species and Mycotoxins in Silage Maize
Toxins 2011, 3(8), 949-967; doi:10.3390/toxins3080949
Received: 1 June 2011 / Revised: 18 July 2011 / Accepted: 20 July 2011 / Published: 4 August 2011
Cited by 20 | PDF Full-text (528 KB) | HTML Full-text | XML Full-text
Abstract
Maize is frequently infected by the Fusarium species producing mycotoxins. Numerous investigations have focused on grain maize, but little is known about the Fusarium species in the entire plant used for silage. Furthermore, mycotoxins persist during the ensiling process and thus endanger [...] Read more.
Maize is frequently infected by the Fusarium species producing mycotoxins. Numerous investigations have focused on grain maize, but little is known about the Fusarium species in the entire plant used for silage. Furthermore, mycotoxins persist during the ensiling process and thus endanger feed safety. In the current study, we analyzed 20 Swiss silage maize samples from growers’ fields for the incidence of Fusarium species and mycotoxins. The species spectrum was analyzed morphologically and mycotoxins were measured by LC-MS/MS. A pre-harvest visual disease rating showed few disease symptoms. In contrast, the infection rate of two-thirds of the harvest samples ranged from 25 to 75% and twelve different Fusarium species were isolated. The prevailing species were F. sporotrichioides, F. verticillioides and F. graminearum. No infection specificity for certain plant parts was observed. The trichothecene deoxynivalenol (DON) was found in each sample (ranging from 780 to 2990 µg kg−1). Other toxins detected in descending order were zearalenone, further trichothecenes (nivalenol, HT-2 and T-2 toxin, acetylated DON) and fumonisins. A generalized linear regression model containing the three cropping factors harvest date, pre-precrop and seed treatment was established, to explain DON contamination of silage maize. Based on these findings, we suggest a European-wide survey on silage maize. Full article
(This article belongs to the Special Issue Trichothecenes)
Open AccessArticle Enzyme-Linked Immunosorbent-Assay for Deoxynivalenol (DON)
Toxins 2011, 3(8), 968-978; doi:10.3390/toxins3080968
Received: 8 May 2011 / Revised: 28 June 2011 / Accepted: 14 July 2011 / Published: 4 August 2011
Cited by 11 | PDF Full-text (217 KB) | HTML Full-text | XML Full-text
Abstract
Deoxynivalenol (DON), one of the trichothecene mycotoxins, is a worldwide contaminant of wheat and barley, especially when infected by Fusarium graminearum, the causative agent of an epidemic wheat disease called Fusarium Head Blight. Because of the high risk of DON ingestion [...] Read more.
Deoxynivalenol (DON), one of the trichothecene mycotoxins, is a worldwide contaminant of wheat and barley, especially when infected by Fusarium graminearum, the causative agent of an epidemic wheat disease called Fusarium Head Blight. Because of the high risk of DON ingestion and the possibility of frequent exposure, it is important to develop a rapid and highly sensitive method for easy identification and quantification of DON in grain samples. In this study, we have developed an indirect competitive enzyme-linked immunosorbent assay (ELISA) to detect DON in wheat. We conjugated 3-O-Hemisuccinyl-DON (3HS-DON) to Bovine serum albumin (BSA) and Ovalbumin (OVA), and obtained DON-specific mice antisera. The indirect competitive ELISA revealed that the optimal concentration of mice serum and the coated antigen was 1/1600 and 1/1500, respectively. The antiserum cross-reacted with the trichothecenes 3-acetyl-DON and T-2 toxin, reaching about 55.2% and 6.3%, respectively, as compared with DON. Results showed that the assay could be performed satisfactorily using an extraction buffer containing less than 15% methanol. Recovery from DON was 82–93% in grains. The linear detection range of DON in grains was between 0.01 and 100 μg/mL. Full article
(This article belongs to the Special Issue Trichothecenes)
Open AccessArticle Accumulation Kinetics of Three Scirpentriol-Based Toxins in Oats Inoculated in Vitro with Isolates of Fusarium sporotrichioides and Fusarium poae
Toxins 2011, 3(5), 442-452; doi:10.3390/toxins3050442
Received: 24 March 2011 / Revised: 27 April 2011 / Accepted: 28 April 2011 / Published: 9 May 2011
PDF Full-text (209 KB) | HTML Full-text | XML Full-text
Abstract
Autoclaved oats were inoculated with a strain of Fusarium sporotrichioides or Fusarium poae. Moisture content of oats after inoculation was at 38%, incubation took place in standing culture at 28 °C. The A-type trichothecenes, 4,15-diacetoxyscirpenol (4,15-DAS), 15-monoacetoxyscirpenol (15-MAS), and scirpentriol (SCIRP) were [...] Read more.
Autoclaved oats were inoculated with a strain of Fusarium sporotrichioides or Fusarium poae. Moisture content of oats after inoculation was at 38%, incubation took place in standing culture at 28 °C. The A-type trichothecenes, 4,15-diacetoxyscirpenol (4,15-DAS), 15-monoacetoxyscirpenol (15-MAS), and scirpentriol (SCIRP) were analyzed by GC/MS. For each strain, three culture flasks were harvested at 2–3 day intervals starting immediately after inoculation. Total incubation time was 42 days (F. poae) and 56 days (F. sporotrichioides). Following peak accumulation, 4,15-DAS decreased below the detection limit for both strains, 15-MAS decreased below this limit for the isolate of F. sporotrichioides, for the isolate of F. poae it decreased to a level markedly below the peak value. SCIRP, after having peaked, decreased to some extent for the strain F. sporotrichioides, with a significant (P = 0.0029) negative linear regression of toxin content against culture age during this period. The content of 15-MAS, and in part also of 4,15-DAS, decreased along with an increase of SCIRP. This sequential accumulation pattern suggests the successive induction of esterases deacetylating 4,15-DAS and 15-MAS, as well as of enzymes involved in the metabolization of the parent alcohol, SCIRP. The results may explain, at least in part, the somewhat higher incidence in naturally contaminated compounds reported in the literature for SCIRP compared to 4,15-DAS and 15-MAS. Full article
(This article belongs to the Special Issue Trichothecenes)

Review

Jump to: Research

Open AccessReview Current and Future Experimental Strategies for Structural Analysis of Trichothecene Mycotoxins—A Prospectus
Toxins 2011, 3(12), 1518-1553; doi:10.3390/toxins3121518
Received: 15 November 2011 / Revised: 12 December 2011 / Accepted: 13 December 2011 / Published: 19 December 2011
Cited by 9 | PDF Full-text (946 KB) | HTML Full-text | XML Full-text
Abstract
Fungal toxins, such as those produced by members of the order Hypocreales, have widespread effects on cereal crops, resulting in yield losses and the potential for severe disease and mortality in humans and livestock. Among the most toxic are the trichothecenes. [...] Read more.
Fungal toxins, such as those produced by members of the order Hypocreales, have widespread effects on cereal crops, resulting in yield losses and the potential for severe disease and mortality in humans and livestock. Among the most toxic are the trichothecenes. Trichothecenes have various detrimental effects on eukaryotic cells including an interference with protein production and the disruption of nucleic acid synthesis. However, these toxins can have a wide range of toxicity depending on the system. Major differences in the phytotoxicity and cytotoxicity of these mycotoxins are observed for individual members of the class, and variations in toxicity are observed among different species for each individual compound. Furthermore, while diverse toxicological effects are observed throughout the whole cellular system upon trichothecene exposure, the mechanism of toxicity is not well understood. In order to comprehend how these toxins interact with the cell, we must first have an advanced understanding of their structure and dynamics. The structural analysis of trichothecenes was a subject of major interest in the 1980s, and primarily focused on crystallographic and solution-state Nuclear Magnetic Resonance (NMR) spectroscopic studies. Recent advances in structural determination through solution- and solid-state NMR, as well as computation based molecular modeling is leading to a resurgent interest in the structure of these and other mycotoxins, with the focus shifting in the direction of structural dynamics. The purpose of this work is to first provide a brief overview of the structural data available on trichothecenes and a characterization of the methods commonly employed to obtain such information. A summary of the current understanding of the relationship between structure and known function of these compounds is also presented. Finally, a prospectus on the application of new emerging structural methods on these and other related systems is discussed. Full article
(This article belongs to the Special Issue Trichothecenes)
Open AccessReview Population Structure and Genetic Diversity of the Fusarium graminearum Species Complex
Toxins 2011, 3(8), 1020-1037; doi:10.3390/toxins3081020
Received: 1 June 2011 / Revised: 11 August 2011 / Accepted: 12 August 2011 / Published: 19 August 2011
Cited by 20 | PDF Full-text (222 KB) | HTML Full-text | XML Full-text
Abstract
The Fusarium graminearum species complex (Fg complex) consists of phylogenetically distinct species some of which cannot be discriminated based on their morphology. Their chemotypes and geographic distributions are dramatically different, and these highlight the challenges that Fusarium head blight (FHB) poses [...] Read more.
The Fusarium graminearum species complex (Fg complex) consists of phylogenetically distinct species some of which cannot be discriminated based on their morphology. Their chemotypes and geographic distributions are dramatically different, and these highlight the challenges that Fusarium head blight (FHB) poses to plant disease specialists and plant breeders, thereby requiring that quarantine officials employ molecular diagnostic tools in their active surveillance programs. Molecular marker technologies play essential roles in species identification of the Fg complex, and they are being used widely to assess the genetic diversity of the clade. The utility, applicability and limitations of molecular methods for assessing the population structure and genetic diversity within the Fg complex are discussed with suitable examples. Knowledge gained from these studies will provide a baseline for monitoring changes in FHB pathogen diversity and mycotoxin potential over time, both of which are critical to the ultimate control and elimination of this economically devastating disease. Full article
(This article belongs to the Special Issue Trichothecenes)
Open AccessReview Trichothecenes: From Simple to Complex Mycotoxins
Toxins 2011, 3(7), 802-814; doi:10.3390/toxins3070802
Received: 26 May 2011 / Revised: 10 June 2011 / Accepted: 29 June 2011 / Published: 1 July 2011
Cited by 59 | PDF Full-text (165 KB) | HTML Full-text | XML Full-text
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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Trichothecenes)

Journal Contact

MDPI AG
Toxins Editorial Office
St. Alban-Anlage 66, 4052 Basel, Switzerland
toxins@mdpi.com
Tel. +41 61 683 77 34
Fax: +41 61 302 89 18
Editorial Board
Contact Details Submit to Toxins
Back to Top