This Article Full Text Full Text (PDF) All Versions of this Article: biophysj.107.116491v1 94/2/656    most recent Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Dague, E. Articles by Dufrêne, Y. F. Search for Related Content PubMed PubMed Citation Articles by Dague, E. Articles by Dufrêne, Y. F.

High-Resolution Cell Surface Dynamics of Germinating Aspergillus fumigatus Conidia

Etienne Dague ^*, David Alsteens ^*, Jean-Paul Latgé  and Yves F. Dufrêne ^*

^* Unité de Chimie des Interfaces, Université Catholique de Louvain, Louvain-la-Neuve, Belgium; and Unité des Aspergillus, Institut Pasteur Paris France, Paris, France

Correspondence: Address reprint requests to Yves F. Dufrêne, Unité de Chimie des Interfaces, Université Catholique de Louvain, Croix du Sud 2/18, B-1348 Louvain-la-Neuve, Belgium. Tel.: 32-10-47-36-00; Fax: 32-10-47-20-05; E-mail: dufrene{at}cifa.ucl.ac.be.

We used real-time atomic force microscopy with a temperature-controlled stage (37°C) to probe the structural and physicochemical dynamics of single Aspergillus fumigatus conidia during germination. Nanoscale topographic images of dormant spores revealed the presence of a layer of rodlets made of hydrophobins, in agreement with earlier electron microscopy observations. Within the 3-h germination period, progressive disruption of the rodlet layer was observed, revealing hydrophilic inner cell wall structures. Using adhesion force mapping with hydrophobic tips, these ultrastructural changes were shown to correlate with major differences in cell surface hydrophobicity. That is, the rodlet surface was uniformly hydrophobic due to the presence of hydrophobins, whereas the cell wall material appearing upon germination was purely hydrophilic. This study illustrates the potential of real-time atomic force microscopy imaging and force spectroscopy for tracking cell-surface dynamics.