Dataset Information

Conidial rodlets of Aspergillus fumigatus

ABSTRACT: Aerial conidia of Ascomycetes and Basidiomycetes are coated with an amphipathic hydrophobin layer commonly called rodlet layer, that renders their surface hydrophobic and resist wetting, thus facilitating effective dispersal in the air. Fungal hydrophobins are small secreted proteins with specific hydropathy patterns and eight cysteine residues ordered in a particular manner which define the two well characterized classes I and II of hydrophobins and a third intermediate class (Kershaw and Talbot, 1998. Littlejohn et al, 2012; Jensen et al, 2010). Wessels 1994). Class I assemblies are generally water insoluble, have an amyloid structure and form the patterned rodlet layer. Class II are smaller proteins than class I and are soluble in aqueous ethanol mixtures of SDS. The intermediate class is a rather heterogenous tote class which would gather non-class I and non-class II hydrophobins without a defined structure. In addition to the role of the rodlet in the fungal life during conidiogenesis and conidial dispersal in the air, it was shown that rodlets can have a role in fungal – host interactions and favour the pathogenic behavior of the fungal pathogens in humans, plant and insect hosts (Talbot et al., 1996, Aimanianda et al, 2009; Zhang et al, 2011). In Aspergillusfumigatus rodlets immunosilence the conidium and their loss from the conidial surface initiates the host immune response (Aimanianda et al., 2009). Our study is focused on the Rod A protein which forms the rodlet structure on the surface of the conidium of A. fumigatus. In spite of their prominent morphological and biological role, the molecular basis for rodlet self-assembly and desagregation in this fungal species has not been understood yet. Point mutations in the rodA gene have helped understanding the mechanism which drives hydrophobin proteins to assemble into highly ordered structures anchored to the conidium surface. Moreover, the biochemical events responsible for the lysis of the rodlets have been investigated.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Aspergillus Fumigatus Cea10

DISEASE(S): Fungal Infectious Disease

SUBMITTER: Magalie Duchateau

LAB HEAD: Jean Paul Latgé

PROVIDER: PXD008503 | Pride | 2021-09-08

REPOSITORIES: Pride

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Publications

Assembly and disassembly of <i>Aspergillus fumigatus</i> conidial rodlets.

Valsecchi Isabel I Lai Jennifer I JI Stephen-Victor Emmanuel E Pillé Ariane A Beaussart Audrey A Lo Victor V Pham Chi L L CLL Aimanianda Vishukumar V Kwan Ann H AH Duchateau Magalie M Gianetto Quentin Giai QG Matondo Mariette M Lehoux Melanie M Sheppard Donald C DC Dufrene Yves F YF Bayry Jagadeesh J Guijarro J Iñaki JI Sunde Margaret M Latgé Jean-Paul JP

Cell surface (Amsterdam, Netherlands) 20190306

The rodlet structure present on the <i>Aspergillus fumigatus</i> conidial surface hides conidia from immune recognition. In spite of the essential biological role of the rodlets, the molecular basis for their self-assembly and disaggregation is not known. Analysis of the soluble forms of conidia-extracted and recombinant RodA by NMR spectroscopy has indicated the importance of disulfide bonds and identified two dynamic regions as likely candidates for conformational change and intermolecular int ...[more]

PMID: 32743139

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Dataset Information

Conidial rodlets of Aspergillus fumigatus

Publications

Assembly and disassembly of <i>Aspergillus fumigatus</i> conidial rodlets.

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