New Viewpoint Over AG-014699 Just Released
""2067" "Dyadic Netherlands, Wageningen, The Netherlands The plant pathogenic fungus Fusarium fujikuroi is the causal agent of bakanae disease on rice due to its ability to produce gibberellins. Besides these phytohormones, F.?fujikuroi is able to produce several other secondary metabolites (SMs). Although much progress has been made in the field of secondary metabolism, the transcriptional regulation of SM biosynthesis is complex and still incompletely understood. Environmental conditions, global as well as pathway-specific regulators and chromatin remodelling have Quetiapine been shown to play major roles. Here, the role of FfSge1, a homologue of the morphological switch regulators Wor1 and Ryp1 in Candida albicans and Histoplasma capsulatum, respectively, is explored with emphasis on secondary metabolism. FfSge1 is not required for formation of conidia and pathogenicity but is involved in vegetative growth. Transcriptome analysis of the mutant ��ffsge1 compared with the wild type, as well as comparative chemical analysis between the wild type, ��ffsge1 and OE:FfSGE1, revealed that FfSge1 functions as a global activator of secondary metabolism in F.?fujikuroi. Double mutants of FfSGE1 and other SM regulatory genes brought insights into the hierarchical regulation of secondary metabolism. In addition, FfSge1 is also required for expression of a yet uncharacterized SM gene cluster containing a non-canonical non-ribosomal peptide synthetase. ""2068" "Melioidosis is an emerging infectious disease of humans and animals in the tropics caused by the soil bacterium Burkholderia LDK378 pseudomallei. Despite high fatality rates, the ecology of B.?pseudomallei remains unclear. We used a combination of field and laboratory studies to investigate B.?pseudomallei colonization of native and exotic grasses in northern Australia. Multivariable and spatial analyses were performed to determine significant predictors for B.?pseudomallei occurrence in plants and soil collected longitudinally from field sites. In plant inoculation experiments, the impact of B.?pseudomallei AG-014699 cost upon these grasses was studied and the bacterial load semi-quantified. Fluorescence in situ hybridization and confocal laser scanning microscopy were performed to localize the bacteria in plants. Burkholderia pseudomallei was found to inhabit not only the rhizosphere and roots but also aerial parts of specific grasses. This raises questions about the potential spread of B.?pseudomallei by grazing animals whose droppings were found to be positive for these bacteria. In particular, B.?pseudomallei readily colonized exotic grasses introduced to Australia for pasture. The ongoing spread of these introduced grasses creates new habitats suitable for B.?pseudomallei survival and may be an important factor in the evolving epidemiology of melioidosis seen both in northern Australia and elsewhere globally.