(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Eukaryota: NE > Opisthokonta: NE > Fungi: NE > Dikarya: NE > Ascomycota: NE > saccharomyceta: NE > Pezizomycotina: NE > leotiomyceta: NE > sordariomyceta: NE > Sordariomycetes: NE > Hypocreomycetidae: NE > Hypocreales: NE > Nectriaceae: NE > Fusarium: NE > Fusarium sambucinum species complex: NE > Fusarium pseudograminearum: NE
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA MIRQIQKRPAGSNANPLFLFHDASGTISNYLALGLLGRDVYAIADSRIKA KGDESLQDMSRRYYALIKSTVAEGTILLGGWSLGGMTALQVAWIFSRDPK VNVAGVLMIDSPFPDYRHALSLALESPPSEDGPASTRSDIEKAMLQTVTM LHKWKIPVWRREPQPHTVMLCAGNDVDSDHVALSLVDQFRDSPTLGWNER AGPSVVNESYPIQGHHFSIFDPRNIDSVTKTIVTVTAAMEMMAPEDDEDY
The closely related species Fusarium graminearum and Fusarium pseudograminearum differ in that each contains a gene cluster with a polyketide synthase (PKS) and a nonribosomal peptide synthetase (NRPS) that is not present in the other species. To identify their products, we deleted PKS6 and NRPS7 in F. graminearum and NRPS32 in F. pseudograminearum. By comparing the secondary metabolite profiles of the strains we identified the resulting product in F. graminearum as fusaristatin A, and as W493 A and B in F. pseudograminearum. These lipopeptides have previously been isolated from unidentified Fusarium species. On the basis of genes in the putative gene clusters we propose a model for biosynthesis where the polyketide product is shuttled to the NPRS via a CoA ligase and a thioesterase in F. pseudograminearum. In F. graminearum the polyketide is proposed to be directly assimilated by the NRPS.
Comparative analyses of pathogen genomes provide new insights into how pathogens have evolved common and divergent virulence strategies to invade related plant species. Fusarium crown and root rots are important diseases of wheat and barley world-wide. In Australia, these diseases are primarily caused by the fungal pathogen Fusarium pseudograminearum. Comparative genomic analyses showed that the F. pseudograminearum genome encodes proteins that are present in other fungal pathogens of cereals but absent in non-cereal pathogens. In some cases, these cereal pathogen specific genes were also found in bacteria associated with plants. Phylogenetic analysis of selected F. pseudograminearum genes supported the hypothesis of horizontal gene transfer into diverse cereal pathogens. Two horizontally acquired genes with no previously known role in fungal pathogenesis were studied functionally via gene knockout methods and shown to significantly affect virulence of F. pseudograminearum on the cereal hosts wheat and barley. Our results indicate using comparative genomics to identify genes specific to pathogens of related hosts reveals novel virulence genes and illustrates the importance of horizontal gene transfer in the evolution of plant infecting fungal pathogens.
