ARS | Publication request: Molecular phylogenetic diversity, multilocus haplotype nomenclature, and in vitro antifungal resistance within the Fusarium solani species complex

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: September 2, 2008
Publication Date: September 2, 2008
Citation: O Donnell, K., Sutton, D.A., Fothergill, A., Mccarthy, D., Rinaldi, M.G., Brandt, M.E., Zhang, N., Geiser, D.M. 2008. Molecular phylogenetic diversity, multilocus haplotype nomenclature, and in vitro antifungal resistance within the Fusarium solani species complex. Meeting Abstract.

Technical Abstract: Members of the species-rich Fusarium solani species complex (FSSC) are responsible for approximately two-thirds all fusarioses of humans and other animals. In addition, many economically important phytopathogenic species are nested within this complex. Due to their increasing clinical relevance and because most of the human pathogenic and plant pathogenic FSSC lack Latin binomials, we have extended the multilocus haplotype nomenclatural system introduced in a previous study (Chang et al., JAMA 296:953-963, 2006) to all 35 species within the medically important FSSC clade 3 to facilitate global epidemiological studies. The typing scheme is based on polymorphisms in portions of the following three genes: the internal transcribed spacer (ITS) region plus domains D1+D2 of the nuclear large subunit (LSU) ribosomal RNA, translation elongation factor (EF-1a), and the second largest subunit of RNA polymerase II (RPB2). Of the 252 isolates subjected to multilocus DNA sequence typing, 192 sequence types were differentiated, and these were distributed among three strongly supported clades designated 1, 2 and 3. All of the mycoses-associated isolates were restricted to FSSC clade 3, and these represent at least 21 phylogenetically distinct species. Analyses of the combined DNA sequence data, using 3 separate phylogenetic methods, yielded the most robust hypothesis of evolutionary relationships and genetic diversity within the FSSC to date. The in vitro activity of 10 antifungals tested against 20 isolates representing 18 species that span the breadth of the FSSC phylogeny show that members of this complex are broadly resistant to these drugs.