Molecular characterization of atoxigenic strains for biological control of aflatoxins in Nigeria
Abstract Aflatoxins are highly toxic carcinogens produced by several species in Aspergillus section Flavi. Strains of A. flavus that do not produce aflatoxins, called atoxigenic strains, have been used commercially in North America as tools for limiting aflatoxin contamination. A similar aflatoxin m...
| Autores principales: | , , , , |
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| Formato: | Journal Article |
| Lenguaje: | Inglés |
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Informa UK Limited
2010
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| Materias: | |
| Acceso en línea: | https://hdl.handle.net/10568/87993 |
| _version_ | 1855517909380497408 |
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| author | Donner, M. Atehnkeng, J. Sikora, R.A. Bandyopadhyay, Ranajit Cotty, P.J. |
| author_browse | Atehnkeng, J. Bandyopadhyay, Ranajit Cotty, P.J. Donner, M. Sikora, R.A. |
| author_facet | Donner, M. Atehnkeng, J. Sikora, R.A. Bandyopadhyay, Ranajit Cotty, P.J. |
| author_sort | Donner, M. |
| collection | Repository of Agricultural Research Outputs (CGSpace) |
| description | Abstract
Aflatoxins are highly toxic carcinogens produced by several species in Aspergillus section Flavi. Strains of A. flavus that do not produce aflatoxins, called atoxigenic strains, have been used commercially in North America as tools for limiting aflatoxin contamination. A similar aflatoxin management strategy is being pursued in Nigeria. In the current study, loci across the 68 kb aflatoxin biosynthesis gene cluster were compared among 18 atoxigenic and two aflatoxin-producing vegetative compatibility groups (VCGs) from Nigeria and an atoxigenic VCG used commercially in North America. Five of the atoxigenic VCGs had large deletions (37–65 kb) extending from the teleomeric side of the aflatoxin biosynthesis cluster. In one VCG (AV0222) the deletion extended through the cluster to the adjacent sugar cluster. The remaining twelve atoxigenic VCGs, including the VCG used for aflatoxin management in North America, contained all the aflatoxin pathway genes, but with defects. Two observations support the long-term persistence of atoxigenicity within A. flavus: first, a comparison of pathway genes revealed more changes in atoxigenic than in aflatoxin-producing isolates relative to the aflatoxin-producing strain NRRL 3357; and second, several non-synonymous changes are unique to atoxigenics. Atoxigenic VCG diversity was assessed with phylogenetic analyses. Although some atoxigenics share relatively recent ancestry, several are more closely related to aflatoxin producers than to other atoxigenics. The current study demonstrates VCGs of A. flavus in West Africa with diverse mechanisms of atoxigenicity and potential value in aflatoxin management programmes. |
| format | Journal Article |
| id | CGSpace87993 |
| institution | CGIAR Consortium |
| language | Inglés |
| publishDate | 2010 |
| publishDateRange | 2010 |
| publishDateSort | 2010 |
| publisher | Informa UK Limited |
| publisherStr | Informa UK Limited |
| record_format | dspace |
| spelling | CGSpace879932024-05-01T08:15:38Z Molecular characterization of atoxigenic strains for biological control of aflatoxins in Nigeria Donner, M. Atehnkeng, J. Sikora, R.A. Bandyopadhyay, Ranajit Cotty, P.J. polymerase chain reaction mycology aflatoxins cereals health significance aspergillus flavi atoxigenic strains vegetative compatibility groups toxicology food science Abstract Aflatoxins are highly toxic carcinogens produced by several species in Aspergillus section Flavi. Strains of A. flavus that do not produce aflatoxins, called atoxigenic strains, have been used commercially in North America as tools for limiting aflatoxin contamination. A similar aflatoxin management strategy is being pursued in Nigeria. In the current study, loci across the 68 kb aflatoxin biosynthesis gene cluster were compared among 18 atoxigenic and two aflatoxin-producing vegetative compatibility groups (VCGs) from Nigeria and an atoxigenic VCG used commercially in North America. Five of the atoxigenic VCGs had large deletions (37–65 kb) extending from the teleomeric side of the aflatoxin biosynthesis cluster. In one VCG (AV0222) the deletion extended through the cluster to the adjacent sugar cluster. The remaining twelve atoxigenic VCGs, including the VCG used for aflatoxin management in North America, contained all the aflatoxin pathway genes, but with defects. Two observations support the long-term persistence of atoxigenicity within A. flavus: first, a comparison of pathway genes revealed more changes in atoxigenic than in aflatoxin-producing isolates relative to the aflatoxin-producing strain NRRL 3357; and second, several non-synonymous changes are unique to atoxigenics. Atoxigenic VCG diversity was assessed with phylogenetic analyses. Although some atoxigenics share relatively recent ancestry, several are more closely related to aflatoxin producers than to other atoxigenics. The current study demonstrates VCGs of A. flavus in West Africa with diverse mechanisms of atoxigenicity and potential value in aflatoxin management programmes. 2010-05 2017-09-21T14:08:05Z 2017-09-21T14:08:05Z Journal Article https://hdl.handle.net/10568/87993 en Limited Access Informa UK Limited Donner, M., Atehnkeng, J., Sikora, R.A., Bandyopadhyay, R. & Cotty, P.J. (2010). Molecular characterization of atoxigenic strains for biological control of aflatoxins in Nigeria. Food Additives and Contaminants, 27(5), 576-590. |
| spellingShingle | polymerase chain reaction mycology aflatoxins cereals health significance aspergillus flavi atoxigenic strains vegetative compatibility groups toxicology food science Donner, M. Atehnkeng, J. Sikora, R.A. Bandyopadhyay, Ranajit Cotty, P.J. Molecular characterization of atoxigenic strains for biological control of aflatoxins in Nigeria |
| title | Molecular characterization of atoxigenic strains for biological control of aflatoxins in Nigeria |
| title_full | Molecular characterization of atoxigenic strains for biological control of aflatoxins in Nigeria |
| title_fullStr | Molecular characterization of atoxigenic strains for biological control of aflatoxins in Nigeria |
| title_full_unstemmed | Molecular characterization of atoxigenic strains for biological control of aflatoxins in Nigeria |
| title_short | Molecular characterization of atoxigenic strains for biological control of aflatoxins in Nigeria |
| title_sort | molecular characterization of atoxigenic strains for biological control of aflatoxins in nigeria |
| topic | polymerase chain reaction mycology aflatoxins cereals health significance aspergillus flavi atoxigenic strains vegetative compatibility groups toxicology food science |
| url | https://hdl.handle.net/10568/87993 |
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