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United States Department of Agriculture

Agricultural Research Service

Research Project: DEVELOPMENT AND APPLICATION OF MOLECULAR PHYLOGENETICS OF FUNGI TO ENHANCE FOOD SAFETY AND FOOD SECURITY

Location: Bacterial Foodborne Pathogens & Mycology Research Unit

Title: A Two-locus DNA Sequence Database for Typing Plant and Human Pathogens Within the Fusarium oxysporum Species Complex

Authors
item O Donnell, Kerry
item Gueidan, Cecile -
item Sink, Stacy
item Johnston, Peter -
item Crous, Pedro -
item Glenn, Anthony
item Riley, Ronald
item Zitomer, Nicholas
item Colyer, Patrick -
item Waalwijk, Cees -
item Van Der Lee, Theo -
item Moretti, Antonio -
item Kang, Seogchan -
item Kim, Hye-Seon -
item Geiser, David -
item Juba, Jean -
item Baayen, Robert -
item Cromey, Matthew -
item Bithel, S -
item Sutton, Deanna -
item Skovgaard, Kerstin -
item Ploetz, Randy -
item Kistler, H
item Elliott, Monica -
item Davis, Mike -
item Sarver, Brice -

Submitted to: Fungal Genetics and Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 20, 2009
Publication Date: December 1, 2009
Citation: O Donnell, K., Gueidan, C., Sink, S.L., Johnston, P.R., Crous, P., Glenn, A.E., Riley, R.T., Zitomer, N.C., Colyer, P., Waalwijk, C., Van Der Lee, T., Moretti, A., Kang, S., Kim, H., Geiser, D.M., Juba, J., Baayen, R.P., Cromey, M.G., Bithel, S., Sutton, D.A., Skovgaard, K., Ploetz, R., Kistler, H.C., Elliott, M., Davis, M., Sarver, B.A. 2009. A Two-locus DNA Sequence Database for Typing Plant and Human Pathogens Within the Fusarium oxysporum Species Complex. Fungal Genetics and Biology. 46(12):936-948.

Interpretive Summary: Members of the Fusarium oxysporum species complex (FOSC) are ubiquitous soil-borne plant pathogens responsible for vascular wilts of a large number of agronomically and horticulturally important crops. Collectively, they represent the most economically important species complex within Fusarium. Given their genetic diversity and large number of host-specific plant pathogens, multilocus DNA sequence typing currently represents the most robust approach for characterizing their genetic diversity and for predicting host specificity. Towards this end, we developed a two-locus database for the identification of host-specific plant pathogens and opportunistic pathogens of humans and other animals. In addition, experiments were conducted to assess the potential of genetically diverse members of the FOSC to produce moniliformin and fumonisin toxins in vitro. The FOSC database will be made web-accessible via the Fusarium-ID database, thereby assisting a broad range of agricultural and medical scientists in identifying these pathogens.

Technical Abstract: We constructed a two-locus database, comprising partial translation elongation factor (EF-1alpha) gene sequences and nearly full-length sequences of the nuclear ribosomal intergenic spacer region (IGS rDNA) for 850 isolates spanning the phylogenetic breadth of the Fusarium oxysporum species complex (FOSC). This database represents a unique resource for typing plant host-specific pathogens (i.e., formae speciales) and opportunistic pathogens of humans. Of the 850 isolates typed, 101 EF-1alpha, 203 IGS rDNA, and 256 two-locus sequence types (STs) were differentiated. Analysis of the combined dataset suggests that two-thirds of the STs might be associated with a single host plant. This analysis also revealed that the 26 STs associated with human mycoses were genetically diverse, including several which appear to be nosocomial in origin. A congruence analysis, comparing partial EF-1alpha and IGS rDNA bootstrap consensus, identified a significant number of conflicting relationships dispersed throughout the bipartitions, suggesting that some of the IGS rDNA sequences may be nonorthologous.

Last Modified: 4/19/2014
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