Fusaric acid detoxification: a strategy of Gliocladium roseum involved in its antagonism against Fusarium verticillioides

The transition from one lifestyle to another in some fungi is initiated by a single orthologous gene, SGE1, that regulates markedly different genes in different fungi. Despite these differences, many of the regulated genes encode effector proteins or proteins involved in the synthesis of secondary metabolites (SM), both of which can contribute to pathogenicity. Fusarium verticillioides is both an endophyte and a pathogen of maize and can grow as a saprophyte on dead plant material. During growth on live maize plants, the fungus can synthesize a number of toxic SM, including fumonisins, fusarins, and fusaric acid, that can contaminate kernels and kernel-based food and feed. In this study, the role of F. verticillioides SGE1 in pathogenicity and secondary metabolism was examined by gene deletion analysis and transcriptomics. SGE1 is not required for vegetative growth or conidiation but is required for wild-type pathogenicity and affects synthesis of multiple SM, including fumonisins and fusarins. Induced expression of SGE1 enhanced or reduced expression of hundreds of genes, including numerous putative effector genes that could contribute to growth in planta; genes encoding cell surface proteins; gene clusters required for synthesis of fusarins, bikaverin, and an unknown metabolite; as well as the gene encoding the fumonisin cluster transcriptional activator. Together, our results indicate that SGE1 has a role in global regulation of transcription in F. verticillioides that impacts but is not absolutely required for secondary metabolism and pathogenicity on maize.

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In planta reduction of maize seedling stalk lesions by the bacterial endophyteBacillus mojavensis

Canadian Journal of Microbiology ◽

10.1139/w11-031 ◽

2011 ◽

Vol 57 (6) ◽

pp. 485-492 ◽

Cited By ~ 20

Author(s):

Charles W. Bacon ◽

Dorothy M. Hinton

Keyword(s):

Fusarium Verticillioides ◽

Fusaric Acid ◽

Maize Seedling ◽

Wild Type ◽

In Planta ◽

Lesion Development ◽

Bacillus Mojavensis ◽

Acid Tolerant ◽

Bacteria And Fungi ◽

Maize Kernels

Maize ( Zea mays L.) is susceptible to infection by Fusarium verticillioides through autoinfection and alloinfection, resulting in diseases and contamination of maize kernels with the fumonisin mycotoxins. Attempts at controlling this fungus are currently being done with biocontrol agents such as bacteria, and this includes bacterial endophytes, such as Bacillus mojavensis . In addition to producing fumonisins, which are phytotoxic and mycotoxic, F. verticillioides also produces fusaric acid, which acts both as a phytotoxin and as an antibiotic. The question now is Can B. mojavensis reduce lesion development in maize during the alloinfection process, simulated by internode injection of the fungus? Mutant strains of B. mojavensis that tolerate fusaric acid were used in a growth room study to determine the development of stalk lesions, indicative of maize seedling blight, by co-inoculations with a wild-type strain of F. verticillioides and with non-fusaric acid producing mutants of F. verticillioides. Lesions were measured on 14-day-old maize stalks consisting of treatment groups inoculated with and without mutants and wild-type strains of bacteria and fungi. The results indicate that the fusaric-acid-tolerant B. mojavensis mutant reduced stalk lesions, suggesting an in planta role for this substance as an antibiotic. Further, lesion development occurred in maize infected with F. verticillioides mutants that do not produce fusaric acid, indicating a role for other phytotoxins, such as the fumonisins. Thus, additional pathological components should be examined before strains of B. mojavensis can be identified as being effective as a biocontrol agent, particularly for the control of seedling disease of maize.

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Methanolic Extracts from Cultivated Mushrooms Affect the Production of Fumonisins B and Fusaric Acid by Fusarium verticillioides

Toxins ◽

10.3390/toxins12060366 ◽

2020 ◽

Vol 12 (6) ◽

pp. 366 ◽

Cited By ~ 1

Author(s):

Daniel Merel ◽

Jean-Michel Savoie ◽

Gerardo Mata ◽

Dulce Salmones ◽

Carlos Ortega ◽

...

Keyword(s):

Lentinula Edodes ◽

Culture Media ◽

Fusarium Verticillioides ◽

Fusaric Acid ◽

Fruiting Bodies ◽

In Vitro Production ◽

Methanolic Extracts ◽

Comparative Metabolomics ◽

Vitro Production

The maize pathogen Fusarium verticillioides and their mycotoxins cause damage to plants, animals, and human health. This work aimed to evaluate the effect of crude extracts (CEs) from Agaricus subrufescens, Lentinula edodes, and Pleurotus ostreatus fruiting bodies on in vitro production of biomass and mycotoxins by two strains of F. verticillioides. Stipes and pilei were separated before extraction for A. subrufescens and L. edodes. Comparative metabolomics and dereplication of phenolic compounds were used to analyze all CEs. Mushroom CEs did not significantly inhibit the production of mycelial biomass at concentrations of 2 mg mL−1. CEs from A. subrufescens (stipes and pilei) and L. edodes pilei inhibited the production of fumonisins B1 + B2 + B3 by 54% to 80%, whereas CE from P. ostreatus had no effect. In contrast, CE from L. edodes stipes dramatically increased the concentration of fumonisins in culture media. Fusaric acid concentration was decreased in cultures by all CEs except L. edodes stipes. Differences in phenolic composition of the extracts may explain the different effects of the CE treatments on the production of mycotoxins. The opposing activities of stipes and pilei from L. edodes offer an opportunity to search for active compounds to control the mycotoxin production by F. verticillioides.

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Current Perspectives of Biocontrol Agents for Management of Fusarium verticillioides and Its Fumonisin in Cereals—A Review

Journal of Fungi ◽

10.3390/jof7090776 ◽

2021 ◽

Vol 7 (9) ◽

pp. 776

Author(s):

Deepa Nagraj ◽

Premila N. Achar ◽

M. Y. Sreenivasa

Keyword(s):

Fusarium Verticillioides ◽

Fusaric Acid ◽

Fumonisin B1 ◽

Food Products ◽

Global Perspective ◽

Fungal Phytopathogen ◽

Major Attention ◽

Physical And Chemical ◽

To Receive ◽

Potential Carcinogen

Fusarium verticillioides is the most predominant fungal phytopathogen of cereals and it is posing great concern from a global perspective. The fungus is mainly associated with maize, rice, sorghum, wheat, sugarcane, banana, and asparagus and causes cob, stalk, ear, root, crown, top, and foot rot. F. verticillioides produces fumonisins as the major secondary metabolite along with trace levels of beauvericin, fusaric acid, fusarin C, gibberiliformin, and moniliformin. Being a potential carcinogen, fumonisins continue to receive major attention as they are common contaminants in cereals and its processed food products. The importance of elimination of F. verticillioides growth and its associated fumonisin from cereals cannot be overemphasized considering the significant health hazards associated with its consumption. Physical and chemical approaches have been shown to reduce fumonisin B1 concentrations among feeds and food products but have proved to be ineffective during the production process. Hence, biological control methods using microorganisms, plant extracts, antioxidants, essential oils, phenolic compounds, and other advanced technologies such as growing disease-resistant crops by applying genetic engineering, have become an effective alternative for managing F. verticillioides and its toxin. The different methods, challenges, and concerns regarding the biocontrol of F. verticillioides and production of fumonisin B1 have been addressed in the present review.

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Identification of gene clusters associated with fusaric acid, fusarin, and perithecial pigment production in Fusarium verticillioides

Fungal Genetics and Biology ◽

10.1016/j.fgb.2012.05.010 ◽

2012 ◽

Vol 49 (7) ◽

pp. 521-532 ◽

Cited By ~ 86

Author(s):

Daren W. Brown ◽

Robert A.E. Butchko ◽

Mark Busman ◽

Robert H. Proctor

Keyword(s):

Fusarium Verticillioides ◽

Fusaric Acid ◽

Gene Clusters ◽

Pigment Production

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Trichoderma and sulphoethyl glucan reduce maize root rot infestation and fusaric acid content

Plant Soil and Environment ◽

10.17221/3593-pse ◽

2011 ◽

Vol 51 (No, 7) ◽

pp. 322-327 ◽

Cited By ~ 3

Author(s):

A. Šrobárová ◽

Š. Eged

Keyword(s):

Cell Walls ◽

Fusarium Verticillioides ◽

Fusaric Acid ◽

Severity Index ◽

Positive Control ◽

Maize Seedlings ◽

Trichoderma Sp ◽

Murashige Skoog ◽

The One ◽

Measurable Concentration

Roots of maize seedlings (cv. Pavla) infested by Fusarium verticillioides (10<sup>5</sup>/ml) were cultivated on Murashige-Skoog medium (MSM, Sigma, USA) containing CaCl<sub>2</sub>,IAA and kinetin. Simultaneously, a strain of the antagonistic fungus Trichoderma sp. and a sulphoethyl glucan (SEG) isolated from the cell walls of Saccharomyces cerevisiae, were added. Two evaluations (on 7 and 14 days) were done. Productivity parameters of leaves and roots (fwt, dwt, and length), disease severity index (DSI) and fusaric acid (FA) concentration were evaluated. Both Trichoderma sp. and SEG increased productivity parameters of plants in infested variants and maintained it on the level of control plants during 14 days of experiment. Trichoderma reduced the DSI, while SEG increased it. DSI correlated with FA concentration. After seven days of cultivation concentration of FA was lower in all infected variants cultivated concomitantly with agents, compared with the one without them. After 14 days of cultivation both agents reduced the concentration of FA up to 50% to the non-measurable concentration in variant with Trichoderma. In variant with positive control, where FA was added to SEG, its concentration decreased up to 30%.

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Fusaric acid, aFusarium verticillioidesmetabolite, antagonistic to the endophytic biocontrol bacteriumBacillus mojavensis

Canadian Journal of Botany ◽

10.1139/b04-067 ◽

2004 ◽

Vol 82 (7) ◽

pp. 878-885 ◽

Cited By ~ 34

Author(s):

C W Bacon ◽

D M Hinton ◽

J K Porter ◽

A E Glenn ◽

G Kuldau

Keyword(s):

Fusarium Moniliforme ◽

Biocontrol Agent ◽

Bacterial Colonization ◽

Fusarium Verticillioides ◽

Fusaric Acid ◽

Endophytic Bacterium ◽

Fungal Endophyte ◽

Plant Diseases ◽

Control Group ◽

In Planta

An endophytic bacterium, Bacillus mojavensis Roberts, Nakamura & Cohan, was patented as a nonpathogenic biocontrol for plant diseases. However, before this bacterium can be used as a biocontrol agent, it must be evaluated against homologous competing organisms, some of which are equally successful endophytes, such as species of Fusarium that are symptomless endophytes, especially on maize. Preliminary field trials using this bacterium as a biocontrol agent against production of the fumonisin mycotoxins caused by infection of maize with Fusarium verticillioides (Sacc.) Nirenberg (= Fusarium moniliforme Sheldon) was less than that observed with greenhouse studies. Fusarium verticillioides and other species produce fusaric acid. Fusaric acid at concentrations as low as 22 µmol/L accounted for a 41% reduction in CFU compared with the control group, while concentrations of 223 µmol/L and higher resulted in total toxicity to the bacterium. Mutants of F. verticillioides that produced low concentrations of fusaric acid did not affect the endophytic CFU of the bacterium in seedlings. These results suggest that fusaric acid accounted for the reduction of bacterial colonization and the resulting poor biocontrol activity and suggested its importance to the fungus is as an antibiotic, which assists in the in planta competition for the intercellular niche colonized by F. verticillioides during its endotrophic state.Key words: Fusarium moniliforme, Fusarium verticillioides, bacterial endophyte, fungal endophyte, fumonisin.

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Occurrence, Pathogenicity, and Mycotoxin Production of Fusarium temperatum in Relation to Other Fusarium Species on Maize in Germany

Pathogens ◽

10.3390/pathogens9110864 ◽

2020 ◽

Vol 9 (11) ◽

pp. 864

Author(s):

Annette Pfordt ◽

Simon Schiwek ◽

Anna Rathgeb ◽

Charlotte Rodemann ◽

Nele Bollmann ◽

...

Keyword(s):

Pathogenic Fungus ◽

Fusarium Species ◽

Fusarium Verticillioides ◽

Fusaric Acid ◽

Elongation Factor ◽

Sensu Stricto ◽

Head Blight ◽

Mycotoxin Production ◽

Federal States ◽

Cereal Grain

Fusarium subglutinans is a plant pathogenic fungus infecting cereal grain crops. In 2011, the species was divided in Fusarium temperatumsp. nov. and F. subglutinans sensu stricto. In order to determine the occurrence and significance of F. temperatum and F. subglutinans on maize, a monitoring of maize ears and stalks was carried out in Germany in 2017 and 2018. Species identification was conducted by analysis of the translation elongation factor 1α (TEF-1α) gene. Ninety-four isolates of F. temperatum and eight isolates of F. subglutinans were obtained during two years of monitoring from 60 sampling sites in nine federal states of Germany. Inoculation of maize ears revealed a superior aggressiveness for F. temperatum, followed by Fusarium graminearum, Fusarium verticillioides, and F. subglutinans. On maize stalks, F. graminearum was the most aggressive species while F. temperatum and F. subglutinans caused only small lesions. The optimal temperature for infection of maize ears with F. temperatum was 24 °C and 21 °C for F. subglutinans. All strains of F. temperatum and F. subglutinans were pathogenic on wheat and capable to cause moderate to severe head blight symptoms. The assessment of mycotoxin production of 60 strains of F. temperatum cultivated on rice revealed that all strains produced beauvericin, moniliformin, fusaric acid, and fusaproliferin. The results demonstrate a higher prevalence and aggressiveness of F. temperatum compared to F. subglutinans in German maize cultivation areas.

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