title: Significance of the class II hydrophobin FgHyd5p for the life cycle of Fusarium graminearum.
abstract: Hydrophobins are small secreted proteins ubiquitously found in filamentous fungi. Some hydrophobins were shown to have functions in fungal development, while others lack known function. Class II hydrophobins from Fusarium graminearum and Fusarium culmorum are characterized by formation of low stability aggregates and their solubility in organic solvents. They are economically relevant to the brewing industry because they can induce beer gushing. Since cellular functions of Hyd5p's are still unknown, we analyzed the influence of FgHyd5p on growth and morphology of F. graminearum using FgΔhyd5 knock-out mutants expressing sGFP under the control of the hyd5 promoter and compared them with the performance of the parent wild type strain. Results demonstrate that FgHyd5p does not affect the colony and hyphal morphology. FgHyd5p affects the hydrophobicity of aerial mycelia but had no obvious function in penetration of hyphae through the water air interface. The hydrophobin affects the morphology of conidia, but not their fitness. Different sources of carbon and nitrogen as well as different pH have no effect on the expression of the hyd5 gene, which was demonstrated to be expressed upon growth of F. graminearum on hydrophobic surfaces.
authors.affiliation: Gregor-Mendel-Straße 4, 85350 Freising, Germany.
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Minenko
authors.affiliation: Gregor-Mendel-Straße 4, 85350 Freising, Germany.
authors.forename: Rudi F
authors.initials: RF
authors.lastname: Vogel
authors.affiliation: Gregor-Mendel-Straße 4, 85350 Freising, Germany. Electronic address: niessen@wzw.tum.de.
authors.forename: Ludwig
authors.initials: L
authors.lastname: Niessen
mesh_terms: D002244:Carbon / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D005670:Fusarium / Q000737:chemistry / Q000166:cytology* / Q000235:genetics / Q000254:growth & development*; D017353:Gene Deletion; D020869:Gene Expression Profiling; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D025301:Hyphae / Q000737:chemistry / Q000166:cytology / Q000254:growth & development; D009584:Nitrogen / Q000378:metabolism; D013172:Spores, Fungal / Q000737:chemistry / Q000166:cytology / Q000254:growth & development
chemical_list: D005656:Fungal Proteins; D002244:Carbon; D009584:Nitrogen
keywords: Conidia; Expression; Hydrophobicity; Morphology; Reporter strain; Δhyd5