Journal article
Taxonomy of Aspergillus section Flavi and their production of aflatoxins, ochratoxins and other mycotoxins
Center for Microbial Secondary Metabolites, Centers, Technical University of Denmark1
University of Tabriz2
Section for Microbial and Chemical Ecology, Department of Biotechnology and Biomedicine, Technical University of Denmark3
Natural Product Discovery, Section for Microbial and Chemical Ecology, Department of Biotechnology and Biomedicine, Technical University of Denmark4
Kasetsart University5
Westerdijk Fungal Biodiversity Institute6
Section for Synthetic Biology, Department of Biotechnology and Biomedicine, Technical University of Denmark7
Fungal Chemodiversity, Section for Microbial and Chemical Ecology, Department of Biotechnology and Biomedicine, Technical University of Denmark8
Department of Biotechnology and Biomedicine, Technical University of Denmark9
Charles University10
Babcock University11
National Academy of Agricultural Science12
Czech Academy of Sciences13
Chinese Academy of Medical Sciences14
...and 4 moreAflatoxins and ochratoxins are among the most important mycotoxins of all and producers of both types of mycotoxins are present in Aspergillus section Flavi, albeit never in the same species. Some of the most efficient producers of aflatoxins and ochratoxins have not been described yet. Using a polyphasic approach combining phenotype, physiology, sequence and extrolite data, we describe here eight new species in section Flavi.
Phylogenetically, section Flavi is split in eight clades and the section currently contains 33 species. Two species only produce aflatoxin B1 and B2 (A. pseudotamarii and A. togoensis), and 14 species are able to produce aflatoxin B1, B2, G1 and G2: three newly described species A. aflatoxiformans, A. austwickii and A. cerealis in addition to A. arachidicola, A. minisclerotigenes, A. mottae, A. luteovirescens (formerly A. bombycis), A. nomius, A. novoparasiticus, A. parasiticus, A. pseudocaelatus, A. pseudonomius, A. sergii and A. transmontanensis.
It is generally accepted that A. flavus is unable to produce type G aflatoxins, but here we report on Korean strains that also produce aflatoxin G1 and G2. One strain of A. bertholletius can produce the immediate aflatoxin precursor 3-O-methylsterigmatocystin, and one strain of Aspergillus sojae and two strains of Aspergillus alliaceus produced versicolorins.
Strains of the domesticated forms of A. flavus and A. parasiticus, A. oryzae and A. sojae, respectively, lost their ability to produce aflatoxins, and from the remaining phylogenetically closely related species (belonging to the A. flavus-, A. tamarii-, A. bertholletius- and A. nomius-clades), only A. caelatus, A. subflavus and A. tamarii are unable to produce aflatoxins.
With exception of A. togoensis in the A. coremiiformis-clade, all species in the phylogenetically more distant clades (A. alliaceus-, A. coremiiformis-, A. leporis- and A. avenaceus-clade) are unable to produce aflatoxins. Three out of the four species in the A. alliaceus-clade can produce the mycotoxin ochratoxin A: A. alliaceus s. str. and two new species described here as A. neoalliaceus and A. vandermerwei.
Eight species produced the mycotoxin tenuazonic acid: A. bertholletius, A. caelatus, A. luteovirescens, A. nomius, A. pseudocaelatus, A. pseudonomius, A. pseudotamarii and A. tamarii while the related mycotoxin cyclopiazonic acid was produced by 13 species: A. aflatoxiformans, A. austwickii, A. bertholletius, A. cerealis, A. flavus, A. minisclerotigenes, A. mottae, A. oryzae, A. pipericola, A. pseudocaelatus, A. pseudotamarii, A. sergii and A. tamarii.
Furthermore, A. hancockii produced speradine A, a compound related to cyclopiazonic acid. Selected A. aflatoxiformans, A. austwickii, A. cerealis, A. flavus, A. minisclerotigenes, A. pipericola and A. sergii strains produced small sclerotia containing the mycotoxin aflatrem. Kojic acid has been found in all species in section Flavi, except A. avenaceus and A. coremiiformis.
Only six species in the section did not produce any known mycotoxins: A. aspearensis, A. coremiiformis, A. lanosus, A. leporis, A. sojae and A. subflavus. An overview of other small molecule extrolites produced in Aspergillus section Flavi is given.
Language: | English |
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Publisher: | CBS Fungal Biodiversity Centre |
Year: | 2019 |
Pages: | 1-63 |
ISSN: | 18729797 and 01660616 |
Types: | Journal article |
DOI: | 10.1016/j.simyco.2018.06.001 |
ORCIDs: | Frisvad, Jens Christian and Larsen, T. O. |
A. Nováková A. vandermerwei Frisvad Arzanlou & Samson Aspergillus aflatoxiformans Frisvad Aspergillus aspearensis Houbraken Aspergillus austwickii Frisvad Aspergillus cerealis Houbraken Aspergillus neoalliaceus A. Nováková Aspergillus pipericola Frisvad Aspergillus subflavus Hubka Biology (General) Ezekiel Ezekiel & Samson Frisvad Frisvad & Houbraken Hubka QH301-705.5 Samson Samson & Houbraken